Firearms on College Campuses: Research Evidence and Policy

Firearms on College Campuses: Research Evidence and Policy Implications

Prepared by

Daniel W. Webster, ScD, MPH

John J. Donohue III, PhD, JD

Louis Klarevas, PhD

Cassandra K. Crifasi, PhD, MPH

Jon S. Vernick, JD, MPH

David Jernigan, PhD

Holly C. Wilcox, PhD

Sara B. Johnson, PhD, MPH

Sheldon Greenberg, PhD

Emma E. McGinty, PhD, MS

October 15, 2016

Corresponding Author:

Daniel W. Webster, ScD, MPH

Johns Hopkins Center for Gun Policy and Research

Johns Hopkins Bloomberg School of Public Health

624 N. Broadway, Rm. 593

Baltimore, MD 21205

410-955-0440

dwebster@jhu.edu

Executive Summary

Restrictions on legal gun owners carrying firearms in public places have been removed or greatly

weakened in most states over the past three decades. Colleges and universities, however, have been

locations that have commonly been allowed to prohibit otherwise legal gun carriers from bringing guns

onto campuses. This exception, however, has recently begun to change. Eight states now have laws that,

generally, allow individuals who can legally carry guns elsewhere to bring guns onto college campuses.

In 24 states, colleges and universities have the authority to allow or forbid civilians from having firearms

on their campuses. A number of additional states considered new laws relevant to carrying firearms on

college campuses during their 2015-2016 legislative sessions.

This report reviews the evidence surrounding the relationship between civilian gun carrying and

violent crime and mass shootings and factors that are unique to public safety on college campuses.

Policies removing restrictions on civilian gun carrying are based on claims or assumptions about civilian

gun use, the impact of state Right-to-Carry (RTC) laws, and the nature of mass shootings that are not

supported by or are contrary to the best available research. The incidence of civilian self-defensive gun

use (SDGU) is difficult to discern as available data are based on self-report, and distinguishing aggressor

from victim in interpersonal altercations can be highly subjective. Nonetheless, data from the National

Crime Victimization Survey indicate that SDGU is relatively rare (about 102,000 self-reported incidents

per year affecting 0.9% of all violent crime victimizations) and is no more effective in reducing victims’

risk of injury than other victim responses to attempted violent crimes. Research led by John Lott, author

of More Guns, Less Crime, suggesting that RTC laws prevent violent crime has important flaws that

biased his findings. The most recent and rigorous research on RTC laws that corrects for these flaws

consistently finds that RTC laws are associated with more violent crime. These findings may seem

counterintuitive because concealed-carry permit holders have, as a group, low rates of criminal

offending and must pass a background check to ensure that they do not have any condition, such as a

felony conviction, that prohibits firearm ownership. But, in states with low standards for legal gun

ownership, legal gun owners account for the majority of persons incarcerated for committing violent

crimes with firearms.

As mass shootings and casualties from those shootings have risen sharply over the past decade,

one rationale for allowing more civilians to carry firearms, both on and off college campuses, is to avert

rampage shootings or stop rampage shooters before additional victims are shot. Central to these

arguments are the notions that “gun-free” zones attract individuals set on mass murder and that armed

civilians frequently thwart or interrupt such shootings. New research on mass shootings involving six or

more victims murdered that occurred in the United States from 1966 to through June 2016 contradicts

these claims. Only 12% of these shootings took place, in whole or in part, in a truly gun-free zone (no

armed security or police or armed civilians) and 5% in a gun-restricting zone (civilian gun possession

prohibited). A separate study of mass shootings involving four or more fatalities, that included domestic

incidents during 2009-2015, found that only 13% occurred in a gun-free or gun-restricting zone.

Successful civilian uses of guns to stop a mass shooting were incredibly rare and about as common as

armed civilians being shot while attempting to respond to mass shooting incidents. Furthermore, the

data show no evidence that RTC laws – which, it is argued, lead to more armed citizens ready to defend

against a mass shooting – reduce mass shootings or the number of people shot in those incidents.

This report also reviews research relevant to the unique context of college campuses, especially

student demographics and characteristics, and the implications for increased access to firearms among

college students. Late adolescence and early adulthood is marked by increases in a variety of risky

behaviors including violence, binge drinking, and drug abuse. Binge drinking, a common behavior among

college students, especially elevates risks for involvement in violent altercations. Risky decision-making

in adolescence and early adulthood is due, in part, to on-going brain development during that stage of

life that can compromise emotional and behavioral regulation, impulse control, and judgment – all of

which are essential for avoiding the circumstances in which firearm access leads to tragedy. Age-specific

homicide offending peaks around the age when youth reach the minimum legal age for purchasing,

possessing, and carrying handguns (19-21 years).

Suicidal behavior that leads to death or hospital treatment peaks at age 16, but remains high

through age 25, covering the age span of most college students. Mental illnesses, such as depression,

that commonly emerge during adolescence and young adulthood, coupled with restricted impulse

control and the stressors that many college students experience, increases the risk of suicidal behavior

among college students. Research demonstrates that access to firearms substantially increases suicide

risks, especially among adolescents and young adults, as firearms are the most common method of

lethal self-harm.

Proposals to allow guns on college campuses must consider the fact that serious assaults and

suicide attempts – which are more likely to be lethal when firearms are present – are far more common

than are the rampage shooting incidents that the policies are purported to prevent. Inserting more

firearms into those assaults and suicide attempts by allowing more people to have firearms on

campuses is likely to lead to more deaths and serious injuries. A recent study identified 85 incidents of

shootings or undesirable discharges of firearms on college campuses in the U.S. from January 2013

through June 2016. Only two of these 85 incidents (2.4%) involved a shooter on a rampage. The most

common incidents were interpersonal disputes that escalated into gun violence (45%), premeditated

acts of violence against an individual (12%), suicides or murder/suicides (12%), and unintentional

shootings or discharges (9%). Campus police much more commonly respond to a variety of violent and

non-violent incidents than to rampage shootings. If those campus officers must assume that any given

student is armed, this may compromise their ability to effectively respond to, and de-escalate, these

incidents.

In summary, available data indicate that policies that allow individuals to bring firearms onto

college campuses are unlikely to lead to fewer mass shootings or fewer casualties from those shootings.

Mass shootings are a growing concern, but are still very rare events. Increasing gun availability in

campus environments could make far more common acts of aggression, recklessness, or self-harm more

deadly and, thus, have a deleterious impact on the safety of students, faculty, and staff.

Aims of this Report

The purpose of this report is to review relevant research and implications associated with

policies that allow the carrying of firearms on college and university campuses. During the past 30

years, a growing number of states have passed laws that make it easier for civilians to legally carry

loaded firearms in public places. However, even as more states adopted so-called right-to-carry (RTC)

laws, these laws generally set aside certain places such as bars, courthouses, schools, and college

campuses where gun carrying is prohibited or that allowed businesses or institutions to declare that

civilians are not allowed to bring firearms onto their premises. Deregulation of civilian gun carrying has

accelerated in recent years in many states including new laws that allow or require state colleges and

universities to allow those who can legally carry firearms in public to bring guns onto college campuses.

Policies that allow civilians who are not explicitly prohibited from carrying firearms in public to

carry concealed loaded firearms onto college campuses are based, in part, on beliefs that such policies

with enhance campus safety including reducing risks of mass shootings. Because there have been no

formal evaluations of policies to allow guns on college campuses – many of these policies are relatively

new – we sought to summarize research relevant to civilian use of guns, the impact of RTC laws on

violent crime and mass shootings, and common patterns in public mass shootings to determine how

well available research aligns with the assumptions underlying policies to allow civilians to bring guns

onto college and university campuses. We also sought to summarize research that is relevant to the

potential increased firearm access among college students and the college campus environment.

Relevant Law Governing Guns on College Campuses

In the United States, laws regulating the purchase, possession, and carrying of firearms --

including on college or university campuses -- may originate at the federal, state, or local levels. Federal

law is primarily codified as part of the Gun Control Act of 1968 and its amendments.

The Gun Control

Act specifically includes language stating that Congress does not intend the Act to preclude state gun

laws unless there is a "direct and positive conflict" between federal and state law. As a result, federal

law acts as a "floor" -- imposing minimum standards applicable everywhere -- rather than as a ceiling for

U.S. gun laws.

One federal law, the Gun Free School Zones Act, forbids the carrying of firearms in school zones

-- subject to certain exceptions.

A "school," however, is defined as one "which provides elementary or

secondary education, as determined under state law."

As a result, colleges and universities are not

covered by this federal law.

Most U.S. law regulating the carrying of firearms originates at the state level. Every U.S. state

permits the carrying of weapons, either concealed or open, under some circumstances. These laws

establish the terms under which a lawful gun owner may obtain a carry permit as well as the places and

circumstances in which the gun may be carried. For example, these laws may allow or forbid carrying of

firearms in places that serve alcohol, churches, or college and university campuses. (See the section of

this report devoted to concealed carrying permit research for more information about these laws).

Localities within a state may sometimes also enact their own gun laws. However, since the late

1980s, many states have enacted firearm preemption laws forbidding localities from enacting some or

all types of gun laws. Today, more than 40 states forbid localities from enacting most types of gun laws.

In fact, just five states generally allow local regulation of guns: Connecticut, Hawaii, Massachusetts,

Illinois, and New York.

Even in these states which lack express preemption of local firearm laws, some

local laws may nevertheless be deemed subject to implied preemption if a court determines that

existing state law evidences an intent by the legislature to occupy the field of regulation or if the local

law would otherwise conflict with state law. Therefore, local law plays little role in regulating carrying of

firearms on college or university campuses.

According to the National Conference of State Legislatures, eighteen states currently ban

carrying a concealed weapon on campus. In twenty-four states, individual institutions have the power

to allow or forbid firearm carrying on campus. In the remaining eight states, firearms must generally be

allowed on campus. In addition, during the 2015-2016 state legislative sessions, similar laws were

considered in other states. None have yet been enacted.

College and university firearm restrictions have been the subject of several recent lawsuits

brought by individuals or groups seeking the ability to carry guns on campus. The results of the lawsuits

have been mixed, often based on the specific language of state law. In Regents of the University of

Colorado v. Students for Concealed Carry on Campus, a student group brought a complaint in 2008

alleging that a University of Colorado policy forbidding the possession of firearms on campus violated a

Colorado state law, the Concealed Carry Act (CCA) enacted in 2003.

The CCA preempts localities from

enacting their own laws regarding concealed carrying of handguns and allows concealed permit holders

to carry their handgun anywhere not specifically excluded by the law. Public elementary, middle, and

high schools are excluded but universities are not. In Regents, the Colorado Supreme Court concluded

that the 2003 state law "divested the Board of Regents of its authority to regulate concealed handgun

possession on campus."

Similarly, in 2011 in Oregon Firearms Educational Foundation v. Board of Education and Oregon

University System, the Oregon Court of Appeals concluded that an administrative rule promulgated by

the State Board of Higher Education forbidding the possession of firearms on campus was preempted by

a prior Oregon state law.

The Oregon preemption law states, in part, that "the authority to regulate in

any manner whatsoever the sale, acquisition, transfer, ownership, possession, storage, or use of

firearms ... is vested solely in the Legislative Assembly." Because the carrying rule promulgated by the

Board of Education had the force of administrative law, it was preempted by this language.

In 2006, the Supreme Court of Utah also struck down a University of Utah policy prohibiting

students, faculty, and staff from carrying guns on campus. In University of Utah v. Shurtleff, the Court

held that Utah's firearm preemption statute -- which specifically applied to "state institutions of higher

education" -- was constitutional within the meaning of the Utah state constitution and prevented the

University from enforcing its policy.

By contrast, in at least two cases, courts have upheld a college or university's ability to ban the

carrying or possession of firearms on campus. In Florida Carry, Inc. v. University of Florida, the plaintiffs

argued that a Florida law permitting the possession of firearms in a person's home or business should

supersede a different Florida law prohibiting firearms on school property (including colleges and

universities). The plaintiffs argued that university dormitories were essentially the students' homes.

The Court concluded that the law forbidding guns on university property should prevail despite a state

preemption law.

In a related Florida case, however, a court concluded that a state university could not

forbid the possession of a firearm in a vehicle parked on school property, as long as the gun was

securely encased in the vehicle.

Finally, in Digiacinto v. The Rector and Visitors of George Mason

University, a non-student but frequent visitor to the George Mason University campus challenged a

University rule forbidding firearms in campus buildings or at campus events. The Virginia Supreme

Court concluded that the University policy violated neither state law nor the federal constitution.

As these cases demonstrate, the outcomes are very fact and state law dependent. In addition,

the case law may or may not address whether the campus or university policies violate the Second

Amendment to the U.S. Constitution. In 2008, the U.S. Supreme Court, in District of Columbia v.

Heller,

concluded that a Washington, D.C. law essentially banning the possession of handguns by

civilians in their homes violated the Second Amendment.

However, the Supreme Court has yet to

determine whether this right extends to carrying firearms in public.

Table 1: Status of State Campus Carry Laws as of May 2016

STATE

BANS CONCEALED

CARRY ON CAMPUS

ALLOWS CONCEALED

CARRY ON CAMPUS

DECISION LEFT TO

INSTITUTION

Alabama

√

Alaska

√

Arizona

√

Arkansas

√*

California

√

Colorado

√

Connecticut

√

Delaware

√

Florida

√

Georgia

√

Hawaii

√

Idaho

√

Illinois

√

Indiana

√

Iowa

√

Kansas

√****

Kentucky

√

Louisiana

√

Maine

√

Maryland

√

Massachusetts

√

Michigan

√

Minnesota

√

Mississippi

√

Missouri

√

Montana

√

Nebraska

√

Nevada

√

New Hampshire

√

New Jersey

√

New Mexico

√

STATE

BANS CONCEALED

CARRY ON CAMPUS

ALLOWS CONCEALED

CARRY ON CAMPUS

DECISION LEFT TO

INSTITUTION

New York

√

North Carolina

√

North Dakota

√

Ohio

√

Oklahoma

√

Oregon

√

Pennsylvania

√

Rhode Island

√

South Carolina

√

South Dakota

√

Tennessee

√*

Texas

√**

Utah

√

Vermont

√

Virginia

√

Washington

√

West Virginia

√

Wisconsin

√***

Wyoming

√

Adapted from information provided by National Conference of State Legislatures, Guns on Campus:

Overview. Available at: http://www.ncsl.org/research/education/guns-on-campus-overview.aspx.

* Certain faculty members may carry weapons on campus but not students or the public.

** Effective August 2016. Private institutions may still choose to ban concealed carry.

*** May prohibit weapons in specific buildings if appropriate signs are posted at every entrance.

****Law takes effect in July 2017. Institutions may prohibit carrying in a campus building if all entrances

have adequate security measures

Legal Context and the Potential for Armed Citizens to Reduce Casualties from Mass Shootings

John Lott, author of the book More Guns, Less Crime, popularized the notion that “gun free

zones” invite mass shootings and contribute to the number of casualties from those events because

there are no armed defenders to interrupt rampage shootings. Specifically, Lott purports that

perpetrators of mass shootings intentionally seek out places where people are barred from carrying

firearms in order to maximize casualties and minimize their risk of being shot. He claims that allowing

civilians to legally carry loaded guns in public places increases the odds that an attempted rampage

shooting will be interrupted and the number of casualties reduced; however, Lott’s claims are

inconsistent with available evidence.

The most prominent justification in support of campus-carry policies relates to the potential for

armed civilians to intervene to reduce the carnage of active shootings. According to the advocates of

allowing civilians to carry firearms on college campuses, some individuals considering perpetrating a

mass shooting will be deterred from attacking places where they stand a likelihood of being confronted

by private citizens carrying firearms. In instances when deterrence fails and attacks are initiated,

campus-carry advocates claim that armed students and staff will be able to intervene and halt gun

rampages and thereby minimize the number of victims killed or wounded in the attack.

Below, we assess the evidence of the three underlying arguments for the campus-carry

movement relevant to mass shootings. First, the occurrence and lethality of mass shootings is drastically

reduced in so-called Right-to-Carry (RTC) jurisdictions.

Second, mass shootings occur almost exclusively

in “gun-free zones,” where civilians are prohibited from carrying loaded firearms on their person. Third,

when shooting rampages do occur, the active shooters are often stopped by armed civilians who

confront the perpetrators.

As campus-carry is a relatively new phenomenon, there is little evidence that confirms or

refutes the thesis specifically in the context of college campuses. However, there are several studies that

assess the three underlying propositions that form the foundation of the campus-carry thesis. Examining

each tenet individually offers valuable insights.

Right-to-Carry Firearm Laws Do Not Reduce Mass Shootings or Casualties from Such Shootings

Advocates for allowing civilians to bring guns onto college campuses and to deregulate carrying

of guns in public places in general commonly cite research and statements by John Lott, an economist

widely known for his claims that deregulating gun possession reaps significant reductions in violent

crime.

17,19

Lott supports his claims with data and analytic methods that others have consistently found

to have important flaws. In the 2

edition of More Guns, Less Crime, Lott reported to have assembled a

dataset of all mass shootings in the United States from 1977 to 1997. He found that the adoption of RTC

laws was associated with a 67% reduction in mass shootings, completely eliminating mass shootings

within five years of enactment. He also claimed RTC laws led to a 75% reduction in deaths from such

shootings and an 81% reduction in persons injured in these shootings. However, an independent team

of researchers tried to reproduce Lott’s findings on RTC laws and mass shootings, and found no

association between such laws and such shootings.

Lott’s claims pertaining to mass shootings and RTC laws are also inconsistent with evidence

about mass shootings assembled in Louis Klarevas’s forthcoming book on the topic.

Klarevas collected

data on 111 high-fatality mass shootings (6 or more people murdered with a gun) from 1966 through

2015. He found that in the 41 states that currently have RTC laws or no regulation of concealed carrying

of firearms for legal gun owners, the average death toll in high-fatality mass shootings increased

following the implementation of a RTC law from a mean of 7.5 before to 8.4 after the law. Moreover,

this pattern of over eight fatalities per incident, on average, held well after five years, contradicting

Lott’s assertion that mass shootings stop occurring within five years of the enactment of RTC laws.

When Klarevas expanded his data set to include all 50 states and the District of Columbia, the average

death toll in gun massacres was slightly higher in states and years where RTC laws were in place (8.4)

than in states and years where there were no RTC laws in place (8.0).

Right-to-Carry (RTC) laws are those that remove discretion from law enforcement in issuing licenses to carry

concealed firearms, provided that applicants are legally permitted to possess guns in their homes and meet any

additional conditions, such as safety training. Laws of this type are also referred to as “Shall Issue” laws because

law enforcement discretion is removed from the decision to issue the permits.

There is No Evidence that “Gun-Free Zones” Facilitate Mass Shootings

When John Lott’s book was reissued in its 3

edition in 2010, he introduced a new concept that

characterized places “where private citizens are not allowed to carry guns”: gun-free zones.

maintained that in locations where someone is bound to be armed, rampage gunmen will be thwarted.

Further, he claimed that mass shooters—knowing they will face far less resistance in places where their

potential victims are unarmed—consciously target gun-free zones. Unfortunately, the concept of a gun-

free zone has never been properly defined. Initially, Lott described gun-free zones as locales “where

private citizens are not allowed to carry guns.” Subsequently, Lott began embracing a looser

conceptualization that deemed entire cities and counties to be gun-free zones, if they were extremely

restrictive in issuing concealed-carry permits.

Another problem with the term “gun-free zone” relates to how proponents of unrestricted gun

carrying define areas as gun free when there are law enforcement officers and armed security guards on

the premises, though civilians are prohibited from carrying their personal firearms on site. Lott

characterized military installations like Fort Hood and the Washington Navy Yard, which have been

attacked by rampage gunmen, as gun free despite the presence of significant armed security personnel.

The implication of this notion of “gun free” is that rampage shooters are only deterred by armed

civilians, not by armed guards and law enforcement. But a bullet fired from a police officer’s firearm has

similar stopping power to a bullet from a civilian’s firearm, and it is probably more likely to hit its

intended target since security and law enforcement personnel are likely to be better trained and

prepared to respond to a rampage shooting than is the average civilian gun carrier.

Sharpening definitions can alleviate the ambiguities and inconsistencies surrounding gun-free

zones and their relationship to mass shootings. In Klarevas’s study of rampage shootings, he argues that

it makes more sense to distinguish between truly gun-free zones – places where there are never armed

personnel stationed on the property and private citizens are prohibited from being armed with personal

firearms by law or appropriate notice – and “gun-restricting zones” – places where private citizens are

barred from carrying personal firearms by law or appropriate notice, yet armed security is routinely

present. Most military bases and college campuses are gun restricting, as they typically have armed

guards and/or armed police on regular patrol, but prohibit civilians from bearing arms. To round out the

possibilities, Klarevas identified “gun-allowing zones” as places where private civilians are not legally

prohibited from carrying personal firearms.

A review conducted by Klarevas of the 111 high-fatality mass shootings (six or more victims

murdered) that occurred in the U.S. since 1966 found that only eighteen have taken place, in whole or in

part, in a gun-free zone or gun-restricting zone. (Three of these eighteen incidents occurred, in part, in

gun-allowing zones.) Of these eighteen high-fatality mass shootings in gun-free or gun-restricting zones,

thirteen took place in bona fide gun-free zones. The remaining five incidents occurred in gun-restricting

zones. Contrary to what Lott argues, 84% of all gun massacres occurred in whole or in part where there

is no evidence that civilian guns were prohibited, and nearly 90% occurred in whole or in part in

locations where civilian guns were allowed or there was armed security or law enforcement. These 111

incidents did not include the mass shooting of police officers in Dallas on July 7 that obviously occurred

in a gun-allowing zone where there were numerous Dallas police officers, campus police, and civilians

openly carrying firearms. Among the wounded were two El Centro College police officers. These data do

not suggest that gun-allowing zones deter gun massacres.

There is also little evidence that perpetrators of mass shootings intentionally seek out their

targets based on whether or not civilians are prohibited from having guns. Most targets of mass

shootings are directed at a specific person, group, or institution with whom the perpetrator has a

grievance.

Everytown for Gun Safety analyzed data on mass shootings using a slightly less conservative

definition than that employed by Klarevas – four persons killed with a firearm, not including the shooter

– for the period 2009-2015 and found that the majority (57%) of the incidents involved a shooter’s

current or former intimate partner or family member. Seventy-one percent of the incidents occurred in

a private dwelling and only 13% occurred in a public location that could qualify as a gun free or gun

restricting zone.

Effective Neutralization of Active Shooters Requires Skills and Experience that Most Civilians Lack

There is an unsupported assumption of campus carry advocates that armed students or staff on

campus will shoot accurately enough to stop the shooter in an active shooting incident without

wounding or killing innocent victims. Shooting accurately and making appropriate judgments about

when and how to shoot in chaotic, high-stress situations requires a high level of familiarity with tactics

and the ability to manage stress under intense pressure. Shooting accuracy in such situations is

influenced by distance, the opponent shooter’s actions, lighting, use of cover, type of gun, and more.

Ability to shoot accurately are also affected by heart rate, breathing, fatigue, and mental stress.

Effective and responsible use of a firearm under the conditions of an active shooting requires

significant training. Yet most RTC laws require only that carry permit holders have weapon familiarity,

perform basic range shooting and, in some cases, minimal crisis-shooting training to qualify to legally

carry a gun. Of course, there are no training or performance requirements in states that do not require

civilians to obtain a permit to carry concealed firearms. There is well-documented research citing the

inaccuracy of police officers who use firearms in crisis encounters, although they receive extensive

training and readiness preparation.

There is no reason to believe that college students, faculty and

civilian staff will shoot accurately in active shooter situations when they have only passed minimal

training requirements for a permit to carry. Generally, college and university students function at a high

rate of mental and emotional stress, with over 50% reporting that they feel so depressed that it is

difficult for them to function.

In addition to the July 7, 2016, mass shooting in Dallas, since January 1, 2015, there have been at least four mass

public shootings (as defined by Lott) that occurred in gun-allowing zones: Christopher Harper-Mercer’s shooting

spree that claimed nine lives at Umpqua Community College in Roseburg, Oregon; William Hudson’s rampage that

claimed six lives at the Tennessee Colony campsite near Palestine, Texas; Syed Rizwan Farook and Tashfeen Malik’s

attack that claimed fourteen lives at a holiday party being held at the Inland Regional Center in San Bernardino,

California; and Jason Dalton’s murder spree that left six dead in Kalamazoo, Michigan. At two of the four locations

(Umpqua and Inland)—and possibly at the other two locations—there were armed civilians present at the time of

the shootings.

Legally Armed Citizens Very Rarely Successfully Intervene to Prevent or Interrupt Mass Shootings

One rationale for allowing guns on campus is that by increasing the number of armed civilians,

you increase the ability of someone to effectively intervene with a gun to stop someone engaging in or

attempting a mass shooting. Opponents of gun-free zones do not just argue that civilians carrying

firearms can prevent mass shootings from occurring in the first place. They also maintain that, should

deterrence fail, armed people will help reduce the bloodshed by neutralizing perpetrators before they

can complete their rampages. In theory, this too sounds logical. Again, Lott is the source of this thesis. In

particular, his central contribution to this debate is his effort to assemble an anecdotal compilation of

thirty-one shootings since 1990 that involved armed civilians intervening and halting rampage gunmen

from completing their objective of killing as many people as possible. Others have seized on his

initiative, and the list of incidents now numbers 39.

But there is one substantial problem with this list. When Klarevas scrutinized the specific

instances where armed civilians purportedly intervened to end a mass shooting in progress, he found

that, in reality, rarely did private citizens with personal guns stop rampages. Of the 39 incidents, the

majority—22 incidents—did not involve mass-shooting scenarios. Instead, they were knife attacks, gun-

brandishing episodes where the weapon was never fired, armed robberies where the criminals never

tried to execute the customers present, and shootings that did not involve enough targeted victims to

constitute a mass shooting. Seventeen of the 39 were actual mass-shooting situations. Out of this

subset, the armed intervenor in six of these incidents was a law enforcement officer or armed security

guard (not a private citizen). In two cases, armed civilians drew their weapons and helped detain the

perpetrators, but only after the shootings had concluded. (Neither defender in these two incidents

actually used his weapon to end the rampage.) In five shootings, the attempted defensive gun uses

failed to stop the attacks, with the armed intervenors shot in three of these instances.

28,

18,

Over a 26-

year period, only four incidents that were actual rampage shootings in progress were terminated by the

actions of an armed civilian.

An FBI study that examined 160 active shootings in the United States during 2000-2013 also

provides reason to be suspect of claims that civilian defensive gun uses figure prominently in

terminating ongoing gun rampages. FBI researchers found only one incident that involved an armed

civilian intervening to end an attack in progress. The civilian in that incident (which is also one of the

interventions cited by Klarevas) involved a U.S. Marine with a concealed-firearms license shooting a man

attacking patrons in a Nevada bar. In another four incidents, the attacks were brought to an end when

armed security guards shot the perpetrators. By contrast, the FBI found that 21 of the 160 active

shooting incidents were interrupted when unarmed civilians confronted and restrained the gunmen. The

FBI’s data suggest that unarmed civilians are more than twenty times likely to successfully end an active

shooting than are armed civilians.

Of course, some incidents could potentially have led to mass shootings had an armed civilian not

intervened quickly to prevent more casualties. Klarevas’s review of civilian-interrupted mass shootings

would miss some instances of this sort. However, allowing more civilians to carry firearms into more

public places could also facilitate more mass shootings. The Violence Policy Center has tracked incidents

in which a concealed carry weapon (CCW) permit holder was alleged to have committed various crimes

of violence and unintentional shootings. They identified 29 CCW holders who perpetrated non-defensive

shootings that involved three or more deaths not including the shooter during the period 2007-2015.

Defensive and Hostile Gun Use by Civilians

Debates surrounding policies about guns on college campuses hinge on differing views about

civilian use of firearms including the likelihood that a person can successfully use a firearm to ward off a

criminal assailant in comparison to the likelihood that a person carrying a gun might be prompted to use

his or her gun in hostile or even criminal ways. Unfortunately, there are no surveillance systems

designed to identify and verify acts of self-defense with guns. The best available data on the

phenomena come from the National Crime Victimization Survey (NCVS) which interviews a nationally

representative sample (after weighting) of approximately 90,000 households and over 158,000

individuals age 12 years and older. Households remain in the NCVS sample for three years and eligible

individuals are interviewed every six months about their experiences in which they were a victim of

crime, any actions that they took in response to the attempted or actual crime, and outcomes such as

whether or not they were injured in the crime. Response rates for households and individuals within

those households are typically around 85%, an exceptional rate for survey research.

David Hemenway and Sara Solnick recently published a study based on data from the NCVS for

the five-year period 2007-2011 to examine the use of guns by crime victims and estimate the effects of

victims using a gun in response to a crime versus others actions commonly taken by crime victims.

During the study period, there were 62 cases in which a NCVS respondent reported being a victim of a

violent crime

iii

and used a gun in self-defense and an additional 65 who used a gun in property crimes or

situations involving only verbal threat to the victim. These 62 incidents represented 0.9% of all violent

crimes reported (6,663) and accounted for 8.1 incidents per 100,000 population per year or a total of

102,478 self-defense gun uses (SDGUs) against violent crimes annually. In less than one fifth of the

incidents of reported SDGU, the offender was also armed with a gun. Seventy-three percent of SDGUs

reported by men and 48% of SDGUs reported by women occurred away from their homes. None of the

SDGUs over the five-year period involved sexual assaults.

Victim Gun Use in Response to Criminal Acts Do Not Affect Victims’ Risk of Injury

In this study, Hemenway and Solnick also examined victims’ risk of being injured after taking any

of thirteen specific actions volunteered by NCVS respondents when asked what they did or tried to do

about the incident while it was going on. Four percent of those who reported a SDGU reported being

injured after attempting to protect themselves with a gun; a virtually identical odds of injury among all

victims who took any act of self-protection. After controlling for a host of contextual factors, self-

defensive gun use did not significantly affect victims’ risk of being injured in the criminal act. Most

victims who are injured in crimes are injured before they can take any protective action. Prior studies

suggesting SDGU reduces victims’ injury risk used NCVS data that did not distinguish victim injuries that

occurred before versus after protective actions such as SDGU took place and, thus, could not ascertain

causal connections between SDGU and injury risks.

33,34

The NCVS does not ask respondents whether they used a gun in a hostile or unlawful manner.

Drawing upon NCVS victimization data for the five years studied by Hemenway and Solnick (2007-2011)

iii

Violent crimes examined include physical assaults, both sexual and non-sexual, and robberies.

and including firearm homicides for those years, there were 3.6 victimizations involving firearms for

every self-reported SDGU in response to a violent crime.

It is unknown what percentage of the criminal

uses of guns nationally were committed by individuals who owned guns legally. However, data from a

nationally representative survey of state prison inmates and determined that of those who were

incarcerated for committing a violent crime with a firearm in the thirteen states with the lowest legal

standards, 60 percent legally possessed the firearms when they committed the crime.

The true incidence of SDGU may be significantly lower than indicated by the NCVS because the

data are based on self-reports and determining who is the aggressor and who is the victim in

interpersonal altercations can be highly subjective. Hemenway and colleagues fielded two surveys of a

nationally representative sample of gun owners to ascertain gun owners’ reports of both defensive uses

of guns and hostile uses of guns against respondents. Respondents were asked to describe these

incidents in some detail and five criminal court judges were asked to review the narratives and assess

the probably legality of self-reported use of guns.

In the majority of the self-reported SDGUs, most

criminal court judges considered the actions taken by the respondent with their guns to be “probably

illegal” due to inadequate justification for using deadly force. The judges’ were told to assume that the

respondent had a valid permit to own and carry the gun, and that the respondent had described the

event honestly.

An alternative source of data on SDGU to the NCVS is a national phone survey of 4,977 gun

owners directed by criminologist Gary Kleck in the early 1990s. In this survey, 56 (1.1%) respondents

reported having used defensively used a gun within the past 12 months in situations in which they

report being the would-be victim of a crime. Kleck used these data to make a projection that 2.5 million

times per year a U.S. citizen used a firearm defensively in situations when someone was committing or

attempting to commit a crime – about 22 times higher than the estimate from the NCVS.

The

projections from Kleck’s survey are discordant with data from other sources relevant to crime and

violence, calling into question the validity of the data. For example, Kleck’s survey data extrapolate to

over 200,000 assailants shot by civilians defending themselves against crime each year. During the early

1990s when the survey was conducted there were approximately 300 deaths per year that were

recorded as justifiable homicides committed by civilians using firearms.

There is no direct measure of

criminals suffering nonfatal wounds as a result of being shot by civilians defending themselves, but the

CDC’s surveillance systems for tracking all deaths and a nationally representative sample of nonfatal

injuries treated in hospitals indicates that there are roughly four to five persons suffering nonfatal

gunshot wounds in assaults or incidents of undetermined intent for every fatal gunshot wound with the

same external cause. That would suggest that about no more than 1,800 persons shot by civilians

defending themselves against criminal attacks for the period that Kleck’s survey projects 200,000 – a

wounding rate more than 100 times higher than indicated in hospital surveillance systems.

The Impact of Laws Expanding Civilians Ability to Carry Firearms in Public Places

In 2005 the National Research Council reviewed the then-current information with data through

2000 concerning the impact of state laws allowing citizens to carry concealed weapons.

Noting that the

estimated effects of so-called right to carry (RTC) laws were highly sensitive to the particular choice of

The NCVS reported a total of 1,784,547 incidents in which respondents reported crime victimization by assailants

wielding firearms and the CDC’s vital records indicate a total of 58,450 homicides with firearms for an average of

368,599 victimizations per year over the five-year period.

explanatory variables, the report concluded that the evidence was too uncertain to determine the

impact of RTC laws on crime.

A major obstacle to generating a valid estimate of this impact was that most of the studies

looking at this question included data for the period from 1985 through the early 1990s when violent

crime rose sharply in certain areas, such as California, New York, and the District of Columbia, owing

principally to the introduction of crack cocaine. Since all three of those jurisdictions and a number of

other states with the worst crack problems (e.g., Maryland, New Jersey) also did not adopt RTC laws,

any panel data analysis that did not control for the criminogenic influence of crack would necessarily

generate a biased estimate of the impact of RTC laws that would make them appear to be either less

harmful or more beneficial than they actually were in influencing crime. This was a major problem for

the original study of RTC laws by John Lott and David Mustard and subsequent analyses by Lott.

17,19,40

But this problem plagues every panel data analysis of RTC laws, except for those that started after the

impact of crack had been full dissipated in the very late 1990s or early 2000s.

A quick but admittedly crude way to address this problem is to present a difference-in-

differences comparison between the 36 states that adopted RTC laws over the period 1977-2012 and

the ten states that did not adopt these laws. By comparing the change in crime from a period before

crack emerged to a year well after its impact had dissipated, one can eliminate the impact of crack on

crime (although of course this simple comparison does not control for other influences on crime that

differed over this period for the two sets of states). Figure 1 shows that the ten non-RTC states enjoyed

a 38.1% drop in their violent crime rate from 1977 to 2012, while the 36 adopting states had almost no

change in violent crime over this period (a decline of 2% over a 35-year period).

This simple evidence is suggestive that RTC laws tend to exacerbate violent crime (controlling for

the influence of crack but not for other explanatory variables). Obviously, this chart would overstate the

harm of RTC laws if, say, the non-adopting states had increased their per capita rates of incarceration or

police personnel more than the adopting states, thereby suppressing violent crime through those

mechanisms (which could then potentially explain the relatively better experience with violent crime

over the 1977-2012 period in the non-adopting states). In fact, the opposite is true. The adopting states

had considerably larger percentage increases relative to the non-adopting states over this time period in

their rates of incarceration (262% vs. 221%) and police staffing (61% vs. 26%). The relatively better

crime performance of non-RTC-adopting states in the raw comparison of in the figure below could be

even greater if one were to control for the influence on violent crime of police and incarceration.

Of course, many factors in addition to police, incarceration, and crack influence crime and the

challenge for researchers who seek to find the impact of a single factor such as RTC laws is to account

for those factors that may also be correlated with RTC adoption in an appropriately specified statistical

model. A number of panel data analyses conducted since the publication of the NRC report have tried

to control for a host of explanatory variables. These models, however, have not adequately controlled

for the criminogenic influence of crack (thereby making RTC laws look better) as well as other factors

that are likely to bias the estimated effects of RTC laws.

See the discussion of Zimmerman (2015) below.

The Most Recent Rigorous Research Studies Find RTC Laws Linked to Increased Violence

Donohue, Aneja, and Webber attempted to address these deficiencies with state panel data

analyses that extended the NRC data by twelve years, during which time eleven additional states

adopted RTC laws, to 1979-2012. Two models were used to explore the relationship between RTC laws

and crime. Model 1 estimated shifts in the level of crime after RTC adoption and model 2 estimated RTC

laws’ association with changes in crime trends or slopes. Both models indicated that violent and

property crime both increased in response to the adoption of RTC laws. Specifically, violent crime was

12.3% higher after adoption of RTC laws and violent crime increases about 1.1% more for each year RTC

laws are in effect.

New and sophisticated techniques are being employed to assist researchers in finding the best

set of control states that have violent crime patterns most similar to the states adopting new laws.

Research by Durlauf, Navarro, and Rivers attempts to sort out the different specification choices

between Aneja, Donohue, and Zhang, and Lott and Mustard, using a Bayesian model averaging

approach.

Applying this technique to analyze the impact of RTC laws using county data from 1979-

2000, the authors find that in their preferred spline (trend) model, RTC laws elevate violent crime rates

by 6.5% in the three years after RTC adoption, with the effects growing over time. A recent report from

the Brennan Center based on state-level data for 1979-2012 indicates that violent crime increased, on

average, 10% following RTC law adoption.

Zimmerman (2015) examined the impact of various crime

prevention measures on crime using a state panel data set from 1999-2010. The findings from this study

revealed statistically significant increases in murder, robbery and assault associated with RTC law

adoption. Estimating so-called synthetic controls for states that adopt new policies is a relatively new

technique to evaluate the impact of state policy changes on violent crime and other outcomes. This

100

200

300

400

500

600

700

Never adopted RTC laws or adopted RTC laws

after 2012

States that adopted RTC laws 1977-2012

Violent Crimes Rate per 100,000 Residents

Changes in violent crime rates in states with and without Right-to-Carry (RTC) laws

from 1977 to 2012.

1977

2012

Rate =

663

10 States

71.9

Rate =

411

Rate =

389

36 States

135.8

Rate =

381

36 States

-38.1%

approach addresses some of the challenges posed by regression analyses with panel data from 50 very

disparate states. Webber, Donohue, and Aneja used this approach and found evidence that RTC laws

increase violent crime by 12% to 18% over the ten years after adoption. These results are broadly

consistent with the bulk of the panel data estimates cited above and are inconsistent with the outlier

results generated using the Lott’s model specifications. One difference between the two analytic

approaches is that the panel data estimates typically found that RTC laws were associated with increases

in both violent and property crime, while the synthetic controls estimates only found evidence that RTC

laws increase violent crime.

Some final comments should be made about the likely mechanisms between adoption of RTC

laws and increased crime, which the statistical studies do not directly address. First, the supporters of

RTC laws frequently cite evidence that permit holders, as a group, are arrested for violent crimes at

relatively low rates.

But the important policy question is whether having a CCW (and carrying a gun on

one’s person or in one’s vehicle) affects CCW holders’ risk of committing acts of violence and whether

having more people carrying firearms will increase or decrease the incidents of violent crime and the

lethality of those incidents. Ready access to a loaded firearm is likely to have a greater impact on risk of

committing serious acts of violence among individuals with a history of violence, recklessness, substance

abuse, or those prone to impulsivity or angry outbursts. Passing a background check when the principal

criteria for denial are a convictions for either a felony crime or misdemeanor domestic battery, having a

current domestic violence restraining order, or having been adjudicated mentally incompetent or a

serious threat to self or others due to mental illness is no guarantee that a person is not prone to

violence and can be trusted to carry a loaded concealed firearm in public places.

44,35

CCW holders do

commit serious crimes with guns including murder and mass shootings.

Second, RTC laws can increase crime in many ways even if the permit holders are not

committing it. The ability to carry a gun may embolden some permit holders to incite criminal

responses to their provocative behavior, as some have alleged in the George Zimmerman case leading to

the death of Trayvon Martin. Criminals may also be more likely to carry weapons in response to RTC

adoption and more likely to be aggressive towards their victims if they fear armed opposition. Guns

carried outside the home because of RTC laws are potentially more likely to be lost or stolen, especially

when left in motor vehicles, which can expand criminals’ access to guns. Finally, the presence of more

guns can complicate the job of police and simply take up more police time as they process applications

and check for permit validity when they confront armed citizens. The recent July 2016 shooting by

police of concealed carry permit holder Philando Castile in Minnesota underscores how the introduction

of a gun by a law-abiding citizen can end in tragedy.

Why the College Campus Environment is Ill-Suited for the Civilian Gun Possession

The broader research literature on civilian gun use and policies that allow civilians to carry

concealed firearms has not examined the experience or implications of policies that allow students,

staff, faculty, or visitors to carry firearms onto college campuses. Relevant to this discussion is the

frequency and nature of events where civilians might use firearms at their disposal, the capacity and

proclivities of adolescents and young adults of typical college age to make prudent decisions about

when or how to use firearms, the onset of severe mental illness during young adulthood, the frequency

of binge drinking of alcoholic beverages among college students and the violence that stems from that

drinking. In addition, suicidal ideation and behavior is common during late adolescence and early

adulthood and increasing access to firearms through policies that allow guns onto college campuses

could increase risk of suicide among college students. Due to a variety of developmental, psychological,

and sociological reasons, age-specific homicide offending rates increase dramatically during

adolescence, peaking at age nineteen, and are highest during the age span of most college students (18-

24 years). Suicide attempts that lead to hospital treatment or death also rise dramatically and peak

during the years that most youth enter college.

A recent study identified 85 incidents of shootings or undesirable discharges of firearms on

college campuses in the U.S. from January 2013 through June 2016. Only two of these 85 incidents

(2.4%) involved a shooter on a rampage. The most common incidents were interpersonal disputes that

escalated into gun violence (45%), premeditated acts of violence against an individual (12%), suicides or

murder/suicides (12%), and unintentional shootings or discharges (9%).

Homicide data obtained from the FBI’s, Uniform Crime Reporting Program, Supplemental Homicide Reports, 2014.

Data on age-specific population estimates were obtained from the Centers for Disease Control and Prevention and

generated by US Census Bureau. https://www.cdc.gov/nchs/about/major/dvs/popbridge/popbridge.htm

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

Rate Per 100,000

Age

Rate of homicide offending by age of suspect, 2014.

Data obtained from the Centers for Disease Control and Prevention’s Web-based Injury Statistics Query and

Reporting System (WISQARS), Fatal and Nonfatal Injury Reports, 2014. https://www.cdc.gov/injury/wisqars/

Brain and Cognitive Development in Adolescence and Emerging Adulthood

Adolescence and emerging adulthood is a time of tremendous change in the biological systems

that support decision-making, emotional and behavioral regulation, and motivation. As has been widely

documented in the lay press and in the scientific literature, the brain’s higher association areas (e.g.,

prefrontal cortex or PFC), among other areas, continue to change well into the third decade of life.

46-48

Areas of the PFC are part of the circuitry that supports self-control, including impulse control and

inhibition, judgment, and long-range planning.

47,49

These skills are essential for safe firearm storage and

use, and for appreciating and avoiding the circumstances in which firearm use is likely to lead to tragedy.

Risky decision-making in adolescence/early adulthood is due, in part, to changes in both

frontal/limbic balance in the developing brain and changes in the connections between the PFC and

limbic subcortical structures that support emotional and behavioral regulation.

While the PFC and

other higher order association areas mature relatively late, limbic areas are dense with hormone

receptors that are awakened during puberty.

Limbic areas play a key role in the circuitry that supports

emotions, reward systems, and drives. When limbic influences predominate, drives toward sex

aggression are heightened, and social relationships become particularly important.

Similarly,

dopamine receptors proliferate in the striatum--part of the brain’s motivational circuitry--before they

proliferate in the PFC, which may also help explain why adolescent behavior is biased toward motivation

rather than inhibition.

Compared with adults and younger children, adolescent decision-makers are particularly

sensitive to social and emotional cues in the environment, and are more sensitive to stress, both

psychologically and biophysiologically.

52-55

A number of studies demonstrate that adolescents’ self-

control is vulnerable in the face of potential rewards (e.g., peer approval and acceptance).

56,57

Similarly,

in laboratory studies, adolescents have been shown to demonstrate poorer emotional regulation in the

context of threat than other age groups. For example, in a self-control task, Dreyfuss et al. found that

compared to their older and younger peers, adolescents, particularly males, were more likely to react

100

200

300

400

500

600

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70 73 76 79 82 85

Rate Per 100,000

Age

Rate of Fatal and Nonfatal Suicide Attempts by Age, 2014

impulsively to threat cues (compared to neutral cues); a finding that was mediated by differences in

limbic activation in brain areas that support emotion regulation.

In summary, typical developmental processes in adolescence are associated with more risk-

taking, and poorer self-control in the transition to adulthood. Guns may be called on in the very

situations in which adolescents are most developmentally vulnerable: in the context of high

emotional arousal, situations that require rapid, complex social information processing, those that

involve reinforcing or establishing peer relationships (i.e., showing off), or in conditions of perceived

threat.

Onset of Mental Illness, Youth Suicide and Access to Firearms

College students are vulnerable to a range of mental health issues. The stress associated with

the life transitions inherent in college attendance – leaving home, exploring new social identities,

developing new peer groups, managing challenging coursework and extracurricular activities – place

students at risk of conditions like depression and anxiety.

The majority of mental disorders have their

onset by age 24.

Studies have demonstrated high prevalence of clinical depression and anxiety among

college students: one study found that 14% of undergraduate students and 11% of graduate students at

a large public University with a demographic profile similar to the overall U.S. student population

screened positive for depression, and 4% of undergraduates and 5% of graduates met criteria for

anxiety.

61,62

Despite the high burden of mental illness among college students, many go untreated.

While mental illness treatment rates vary across campuses, one study of students on 26 campuses

across the U.S. found that on average, only 36% of students who screened positive for mental illness had

received treatment in the past year.

Of particular concern in the context of proposals to allow students to carry firearms on campus

is the risk of suicide associated with mental illnesses, especially depression, among this group. In a

national survey of undergraduates conducted in 2015 about events within the past 12 months, 8.9%

reported “seriously considering attempting suicide” and 1.4% had attempted suicide.

A study of

students from 645 U.S. college campuses found increased rates of suicide among college students in

2008-2009 compared to 2004-2005: the suicide rate increased from 6.5 to 7.7 per 100,000 students.

Importantly, a firearm was the leading method for suicide among males, accounting for nearly a third

(31%) of all suicides among male college students.

For females, firearms were the third leading cause

of suicide (10% of all suicides in this group), behind hanging (29%) and poison (16%).

This gender

differential in firearm suicide on college campuses mirrors the differential in the overall U.S.

population.

A large body of literature clearly shows that firearm access is associated with increased

rates of suicide, suggesting that increased access to firearms on college campuses could significantly

increase suicide in this vulnerable group.

67,68

The combination of challenges with impulse control, emotional regulation, and onset of mental

illness contribute to high rates of suicide and suicide attempts among adolescents and young adults. In

2014, suicide was the second leading cause of death in the U.S. among college age youth 17-24 years

old.

Between 1999 and 2014, the suicide rate in this age group increased 12% from 11.3 to 12.7 per

100,000.

Firearms represent an extremely lethal means of intentional self-harm; approximately 90% of

suicide attempts with a firearm resulted in a fatality compared to 3% for poisoning attempts.

In 2014

among males age 17-24 who died by suicide, 49% used a firearm.

Some suicide risk factors differ among those under age 25 compared to older populations.

Emotional control, impulsivity, and decision making continue to develop into the mid-20s, which can put

youth at higher risk for suicide.

In addition to being more impulsive, young individuals tend to be more

vulnerable to a contagion effect after exposure to suicide within their community.

Suicide risk is often

highest in the early stages of the onset of major psychiatric conditions and these symptoms often first

develop in childhood or early adolescence.

60,73

The risk of suicide among youth also increases with age;

2.6 per 100,000 among boys age 10-14 compared to 22.9 per 100,000 among young men age 20-24.

Suicide attempts (whether fatal or nonfatal) may occur in the context of an underlying mental

health condition such as depression and/or alcohol or drug misuse.

74,75

Many suicides also have an

impulsive quality and are often precipitated by an acute stressor (e.g. loss of a relationship, trouble with

the law or school, humiliation, job loss).

The majority of those who survive an attempt do not go on to

die by suicide; a suicide prevented is a life saved.

The lethality of a given means or method of suicide attempt accounts for a substantial portion of

the variation observed in suicide mortality and points to the unrealized potential for means restrictions

strategies to reduce suicide. The method used for a suicide attempt depends on availability; there is a

strong association between the availability of firearms in households and death by suicide. Having ready

access to firearms is linked with suicide not only for the gun owner but for all members of the

household, especially for children and adolescents.

76-78

Studies of the relationship between the presence of guns in the home and risk for suicide among

younger populations have found that the risk of suicide is two- to five-fold higher for all household

members in homes with firearms.

76,77,79,80

These studies have reported limited evidence of substitution

of methods; restricting access to firearms did not lead to increased use of other methods of suicide

attempt. An analysis of changes to Connecticut and Missouri’s permit to purchase handgun purchaser

licensing laws also indicate that these laws – which both screen out some individuals at high risk of

suicide and reduce guns purchased in response to a suicidal impulse – play a role in reducing firearm

suicide risk.

Reducing the availability of highly lethal and commonly used suicide methods has been

associated with declines in suicide rates of as much as 30%–50% in other countries and can be especially

influential in younger populations.

Safe gun storage practices (e.g., using a gun safe or storing ammunition separate from an

unloaded gun), which can be required by state law, are associated with a decreased risk for adolescent

suicide.

This association is especially strong in the 15-19 year old age group, which implies that

restricting access to a firearm is likely to have the biggest impact during the age characterized by higher

impulsivity.

The potential for unsafe storage of firearms, if firearms were permitted in college dorms, is

a concern and could elevate suicide risks to anyone who has access to a firearm owner’s room.

Alcohol Abuse and Violence on College Campuses

A large international literature has established a close association between alcohol use and

violence.

Culture can structure and determine the strength of this relationship through such variables

as frequency of drinking to intoxication or consumption of high-alcohol beverages, and expectations

about drinking behavior or the situational appropriateness of aggression.

College drinking cultures

possess all of these attributes. U.S. college students drink frequently and at high levels: nearly 60% of

18-22 year-old college students reported drinking the past month; 37.9% reported binge drinking

(defined as five or more drinks within two hours).

Among young men in particular, research has found

that expectations about the acceptability of violent action while intoxicated may precede actual acts of

violence while drinking.

Among college students, there appears to be a normative belief that abusive

behavior is more common and less abusive when alcohol is involved for psychological and moderately

severe physically abusive behaviors.

The interaction between college drinking cultures and violent behavior helps to explain the high

prevalence of alcohol-related violence in college populations. In the general population, CDC estimates

that every year, there are 7,756 homicides attributable to alcohol use; 1,269 of these happen to persons

younger than 21.

Hingson et al. have estimated that 600,000 college students annually are assaulted

by another student who has been drinking.

The Bureau of Justice Statistics reported that alcohol was

involved in 41% of on-campus violence and 37% of off-campus violence for students who lived on

campus, and 18% of on-campus violence and 31% of off-campus violence for students living off

campus.

Sexual violence is another significant risk when alcohol is in the mix. On college campuses,

88%of male college rapists who used force to commit the rape also used alcohol or drugs, and college

males who rape incapacitated women are more likely to drink right before the rape.

Alcohol use also

increases the likelihood of assault occurring for women. A meta-analysis and systematic review have

concluded there is a clear positive association between alcohol consumption and physical and sexual

violence for women. Longitudinal data suggests this relationship is bidirectional, meaning that women

who are victims of interpersonal violence tend to drink more and women who drink more are more

likely to be victims of interpersonal violence.

One factor that can moderate the relationship between alcohol use and violence on campus is

the density of alcohol outlets around a college campus. According to one study of 32 colleges, on- and

off-premise outlet densities were associated with campus rape-offense rates. Student drinking level was

associated with both campus rape and assault rates, and mediated the effects of on- and off-campus

alcohol outlet density. Campuses with greater densities of alcohol outlets had higher drinking levels,

which in turn explained higher rates of violence on those campuses.

Thus both culturally and ecologically, college campuses can present a “lit fire” in which

interpersonal violence is prevalent (according to the Bureau of Justice Statistics, one in 10 college

students has experienced a violent crime

), and worsened by the addition of alcohol use. To this

potentially incendiary situation should be added data on the relationship between gun ownership on

college campuses and alcohol use. Two studies from the 1990s looked at this relationship. One found

that students with guns were more likely to be binge drinkers and to need to start the day with

alcohol;

the other revealed that those who self-reported binge drinking or engaging in risky or

aggressive behavior after drinking were not only more likely to have guns at college but also more

likely to be threatened by a gun while at college.

Implications of Guns on Campus for Campus Security and Law Enforcement

For a police officer, the decision to apply deadly force is taken seriously and discussed in training

throughout his or her career.

The decision in a crisis, such as an active shooter event, occurs in an

atmosphere of chaos and panic, and is often over in a matter of minutes, if not seconds.

Like police

officers, students or faculty attempting to use a gun to end an active shooter situation would be

expected to assess the situation, ensure a clear line of fire, shoot well, minimize loss, and bring the

situation to closure. While an entire active shooter situation may last longer, the actual shooting and

opportunity to stop the suspect may be momentary.

Police officers routinely experience high anxiety/high threat situations – including home

invasions, intrusion alarms, armed robberies, suspicious circumstances, traffic stops, and prowlers – and

are prepared to take whatever action is necessary to safely end these incidents. Despite their training

and frequent exposure to high-risk and life-threatening events, evidence shows that police officers do

not shoot accurately in a crisis encounter; though officers who participate in simulation or other high-

stress training tend to shoot somewhat more accurately in a crisis than those who do not.

24,100-103

The

idea that students or faculty could shoot as well as trained police officers in an active shooter situation is

highly questionable given what we know about police performance in high stress situations.

Additionally, consideration must be given to the possibility of police officers not being able to

differentiate a student or faculty member with a gun from the perpetrator during the response to an

active shooter situation. There are numerous examples of this happening, creating confusion and, in

some instances, resulting in civilians being unintentionally shot by law enforcement.

Much of the discussion and debate about allowing the carrying of guns on campus revolves

around this concern over active shooters; however, the issue is more extensive.

104

While active shooter

situations are rare, colleges and universities have responded well to this threat by establishing policies

and plans, conducting training and drills, implementing threat assessment teams, and embracing the

national Incident Command System.

105-107

There are other situations that occur far more frequently on

college campuses, such as disorderly conduct, abuse of alcohol and dangerous substances, intimate

partner violence, suicide threat, faculty-student disputes, fights, and trespass. These types of incidents

deserve more attention because response to these incidents will change based on the potential increase

in the presence of guns due to laws allowing the right to carry on campus.

While there is no evidence to aid in predicting how many students will carry guns on campus if

bans are lifted, campus police and security officers must assume that weapons may be present in many

situations, especially those involving groups and crowds.

108

Most campus officers routinely respond to

situations in which information is sparse. They respond to calls such as “suspicious person,” “suspicious

circumstance,” “911- hang up,” and “alarm sounding” often with no additional information. If the

presence of guns must be assumed, the level of seriousness, tactics used, and necessary precautions

taken in response to such calls are elevated. Tactical changes may include greater reliance on back up

officers, assessing and questioning individuals about the presence of weapons, scanning the

environment for protective cover, and moving quickly to resolve aggression and threat without limiting

the time spent to de-escalate. Local and state police who are called to assist in campus situations will

implement similar precautions and changes in approach. The perception of increased likelihood of

situations in which there may be a gun present could simultaneously increase the risk of shooting,

intentional or otherwise, by police or campus security while responding to calls.

Conclusion

The best available research contradicts many claims and assumptions that underlie policies to

allow civilians to bring firearms onto college campuses. Gun ownership and gun carrying in many states

is common, but successful and warranted civilian defensive gun use is relatively rare. Concealed carry

permit holders have passed criminal background checks and, as a group, commit crimes at a relatively

low rate. But, in states with the most lax standards for legal gun ownership, 60%of individuals

incarcerated for committing crimes with guns were legal gun owners when they committed their crimes.

Some who are legally allowed to own and carry firearms in public places have histories of violence and

recklessness. Many states relaxed restrictions on concealed and open carrying of firearms based on

claims that such policies reduced violent crime. But the best available evaluations of these policies

indicate that these right-to-carry laws increase violence.

Some have blamed rampage shootings, including those on college campuses, on “gun free

zones,” and they have claimed that the best deterrent to such shootings is to remove virtually all

restrictions on civilian gun carrying. Indeed, much of the impetus for policies to allow guns on college

campuses has been to reduce mass shootings or the number of casualties from those shootings by

enabling armed civilians to intervene. Yet the number of people shot in mass shootings in the U.S. has

increased dramatically during the past decade – a period that coincides with the removal of restrictions

on public gun carrying and a push to make gun carrying in public more normative. New research on

fatal mass shootings demonstrates that: 1) right-to-carry laws do not decrease mass shootings or the

average number of people shot in those incidents; 2) the overwhelming majority of fatal mass shootings

occur in places where guns are allowed; and 3) when rampage shootings do occur, very rarely are they

stopped by gun-wielding civilians.

While the net effect of right-to-carry gun policies have negatively impacted public safety

broadly, their effects are likely to be far more deleterious when extended to college campuses. Risks for

violence, suicide attempts, alcohol abuse, and risky behavior are greatly elevated among college-age

youth and in the campus environment. The presence of firearms greatly increases the risk of lethal and

near-lethal outcomes from these behaviors and in this context. Even if allowing more guns on college

campuses did have some protective effect against rare mass shootings on campuses – and available

evidence suggests that this is not the case – the net effect on the safety of college students, faculty, and

staff is likely to be more deaths, more nonfatal gunshot wounds, and more threats with a firearm that

are traumatizing to victims.

Author Bios

Daniel W. Webster, ScD, MPH

Daniel W. Webster, ScD, MPH, is a Professor of Health Policy and Management at the Johns Hopkins

Bloomberg School of Public Health, where he serves as Director of the Center for Gun Policy and

Research and Deputy Director of Research for the Center for the Prevention of Youth Violence. He is one

of the nation’s leading researchers studying gun policy and has published numerous articles on the

prevention of gun violence, firearm policy, youth gun acquisition and carrying, intimate partner violence,

and the prevention of youth violence. He is co-editor and contributor to Reducing Gun Violence in

America: Informing Policy with Evidence and Analysis (Johns Hopkins University Press, 2013). Dr.

Webster helps lead the Johns Hopkins-Baltimore Collaborative for Violence Reduction and conducting

studies evaluating the effects of various efforts to reduce violence, including state gun policies, policing

strategies focused on deterring gun violence, drug law enforcement practices on gun violence, and a

community gun violence prevention initiative. He is also leading a study of Baltimore’s underground gun

market. Dr. Webster teaches courses in violence prevention at Johns Hopkins Bloomberg School of

Public Health. He has advised the White House, Congressional leaders, state and local officials on

policies to reduce gun violence. In 2015, Dr. Webster received the American Public Health Association’s

David Rall Award for Science-Based Advocacy.

John J. Donohue, III, PhD, JD

John J. Donohue III is the C. Wendell and Edith M. Carlsmith professor of law at Stanford University. He

is well known for using empirical analysis to determine the impact of law and public policy in a wide

range of areas, including examinations of the impact on crime of the death penalty, incarceration, guns,

and the legalization of abortion. Other work by Donohue has explored the benefits from stronger efforts

to fight racial discrimination in employment and in school funding, and examined the issues involved in

the regulation of illegal substances. Before rejoining the Stanford Law School faculty in 2010, Professor

Donohue was the Leighton Homer Surbeck professor of law at Yale Law School. Earlier in his career, he

was a law professor at Northwestern University as well as a research fellow with the American Bar

Association. Additionally, he clerked with Chief Justice T. Emmet Clarie, of the U.S. District Court of

Hartford, Connecticut. He is a member of the American Academy of Arts and Sciences, the former

empirical editor of the American Law and Economics Review, and the former president of the American

Law and Economics Association. He received his B.A. from Hamilton College, his J.D. from Harvard

University, and his Ph.D. in economics from Yale University.

Louis Klarevas, PhD

Dr. Louis Klarevas is Associate Lecturer in the Department of Global Affairs at the University of

Massachusetts – Boston. He is the author of Rampage Nation: Securing America from Mass Shootings

(Prometheus Books, forthcoming in 2016). A former Senior Fulbright Scholar in Security Studies, he has

also taught at American University, George Washington University, the City University of New York, and

New York University. During the early phases of the Iraq War, he served as the Defense Analysis

Research Fellow at the London School of Economics. Before joining the ranks of academia, he served as

a research associate at the United States Institute of Peace. His articles and commentaries have

appeared in a variety of prominent news outlets, including The Atlantic, Forbes, The New Republic, The

Huffington Post, The New York Daily News, New York Newsday, The Washington Post, The Washington

Times, and Vice. He has also appeared as an expert on numerous news networks, including ABC, BBC,

CBS, CNN, and NPR. Dr. Klarevas holds a B.A. from the University of Pennsylvania and a Ph.D. in

International Relations from the School of International Service at American University.

Cassandra K. Crifasi, PhD, MPH

Dr. Crifasi is an Assistant Professor in the Department of Health Policy and Management at the Johns

Hopkins Bloomberg School of Public Health and a core faculty member in the Center for Gun Policy and

Research and the Center for Injury Research and Policy. Her research focuses on injury epidemiology

and prevention, firearm policy, and the development, implementation and evaluation of policies,

practices, and procedures on public safety and first responders. She teaches courses in research and

evaluation methods for health policy and currently serves as the Deputy Director of the Johns Hopkins-

Baltimore Collaborative for Violence reduction. Dr. Crifasi’s recent research examined the affect

changing state policies have on the assault and homicide of law enforcement officers in the United

States. She received her PhD in Health Policy and Management in 2014 from the Johns Hopkins

Bloomberg School of Public Health and an MPH in Environmental and Occupational Health from the

Drexel University School of Public Health in 2010.

Jon S. Vernick, JD, MPH

Jon S. Vernick, JD, MPH, is an Associate Professor of Health Policy and Management at The Johns

Hopkins Bloomberg School of Public Health and Co-Director of the Johns Hopkins Center for Gun Policy

and Research. Jon Vernick is the primary instructor for courses on Issues in Injury and Violence

Prevention, and Public Health and the Law. He is also Co-Director of the MPH/JD Program at Johns

Hopkins. Jon Vernick’s research has concentrated on ways in which the law and legal interventions can

improve the public's health. He is particularly interested in epidemiologic, policy, legal, and ethical issues

associated with the prevention of firearm and other injuries. He has also studied legal aspects of motor

vehicle safety, tobacco control, public health preparedness, and obesity prevention, having published

more than 75 scholarly articles and reports on these and other topics. Prof. Vernick is committed to

translating research findings into policy change, regularly working with legislators, media, courts, and

advocates to provide information about effective policies. Jon Vernick earned his BA from the Johns

Hopkins University, a JD with honors from the George Washington University, and an MPH from the

Johns Hopkins Bloomberg School of Public Health.

David Jernigan, PhD

David Jernigan, PhD, directs the Center on Alcohol Marketing and Youth (CAMY) and is an Associate

Professor in the Department of Health, Behavior and Society at the Johns Hopkins Bloomberg School of

Public Health, where he teaches courses on media advocacy, alcohol policy, and campaigning and

organizing for public health. He is also co-director of the Maryland Collaborative to Reduce College

Drinking and Related Problems, a statewide effort involving 14 institutions of higher education

committed to reducing alcohol-related problems on campus and in the surrounding communities. Dr.

Jernigan serves on the boards of Behavioral Health System Baltimore and the Global Alcohol Policy

Alliance, and on advisory boards for Cancer Research UK and the UK Center for Tobacco and Alcohol

Studies. He has written more than 90 peer-reviewed journal articles, co-authored three books and

monographs, and contributed chapters to six books on alcohol issues. He has served as an advisor to the

World Bank and the World Health Organization (WHO) and was the principal author of WHO’s first

Global Status Report on Alcohol and Global Status Report on Alcohol and Youth, and co-author of

Alcohol in the Developing World: A Public Health Perspective and Media Advocacy and Public Health:

Power for Prevention. He has also trained thousands of students and public health advocates in media

advocacy, the strategic use of the mass media to influence public health policy.

Holly C. Wilcox, PhD

Holly C. Wilcox, Ph.D is an Associate Professor in the Johns Hopkins School of Medicine Department of

Psychiatry and the Bloomberg School of Public Health Department of Mental Health. Dr. Wilcox has

spent the past 25 years actively engaged in suicide prevention in schools, universities, emergency

departments, and with the United States Marine Corps. Dr. Wilcox’s most significant contributions have

been in three areas: 1) large population-based, prospective cohort studies of youth suicidal behaviors; 2)

the evaluation of impact of community-based universal prevention programs targeting youth suicidal

behaviors; 3) the identification of biomarkers to inform suicide prevention. Dr. Wilcox led a national

project to identify research needs for data linkage and analyses of linked data to serve as the

foundation for a National Institutes of Health Pathway to Prevention workshop on suicide prevention.

She is the co-chair of the Suicide Prevention Task Group of the National Network of Depression Centers,

a non-profit 501(c)(3) network of 23 leading academic medical center

s. She has offered since 2005 a

course at Johns Hopkins entitled Suicide as a Public Health Problem.

Sara B. Johnson, PhD, MPH

Sara Johnson is Associate Professor of Pediatrics at the Johns Hopkins School of Medicine, with a joint

appointment in the Johns Hopkins Bloomberg School of Public Health’s Department of Population,

Family, and Reproductive Health. She also serves the Director of the Rales Center for the Integration of

Health and Education, which is focused on reducing health and educational disparities in children and

adolescents using school-based health care and wellness programs. Her research is broadly focused in

two areas: 1) how early adversity such as poverty and trauma impacts brain, cognitive, and

neuroendocrine system development from the prenatal period to adolescence; and 2) translating

developmental science to inform evidence-based health and social policies.

Sheldon Greenberg, PhD

Sheldon Greenberg, Ph.D., is Professor of Management in School of Education, Division of Public Safety

Leadership. He served as Associate Dean for more than a decade, during which time he led the Police

Executive Leadership Program and established University partnerships with the U.S. Secret Service and

U.S. Immigration and Customs Enforcement (ICE). His primary research interests are police patrol, the

relationship between police and public health, police organizational structure, highway safety, campus

and school safety, the role of the police in community development, and community organizing. Prior to

joining Johns Hopkins, Dr. Greenberg served as Associate Director of the Police Executive Research

Forum, the nation’s largest law enforcement think tank and center for research. He began his career

with the Howard County, MD, Police Department, where he served as a patrol officer, supervisor, and

director of the police academy, director of research and planning, and commander of the administrative

services bureau. He worked with the U.S. Marshals Service, U.S. Border Patrol, Department of Justice,

and Department of State, as well as with police agencies in Cyprus, Jordan, Kenya, Panama, Hungary,

Pakistan, and the Czech Republic. Dr. Greenberg served on national commissions and task forces on

violence in schools, race-based profiling, and police response to people who have mental illness, police

recruiting, highway safety, military deployment, and homeland defense. He serves as a member of the

Federal Law Enforcement Training Accreditation Board.

Emma E. McGinty, PhD

Dr. McGinty is an Assistant Professor in the Department of Health Policy and Management at JHSPH, and

a core faculty member of both the Center for Gun Policy and Research and the Center for Mental Health

and Addiction Policy Research. Her research focuses on how public policies affect mental health,

substance use, and gun violence. Dr. McGinty's recent research examined the effects of news media

coverage of mass shootings by persons with mental illness on Americans' support for gun policies and

attitudes toward individuals with serious mental illnesses. At the Center for Gun Policy and Research, Dr.

McGinty uses public opinion surveys and message framing experiments to assess public support for gun

violence prevention policies and collaborates on studies of the effects of youth-focused firearm

restrictions and policies designed to prevent the diversion of guns to criminals. She received her PhD in

Health Policy and Management in 2013 from the JHSPH where she was a Sommer Scholar and received

an MS in Health and Behavior Studies from Columbia University in 2006.

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