Guns, laws and public shootings in the United States

ABSTRACT

Since the late 1990s, there have been increasing numbers of public shootings carried out with firearms in the United States. These tragedies continually renew the regulatory debate concerning public safety while considering civil liberties. Using a unique data set, we investigate whether laws correspond to whether an event occurs and the effects of event-specific characteristics on public shooting outcomes. In particular, we analyse how state-specific gun laws, the types of firearms, the shooting venues and the mental health of the gunman impact the outcomes of public shootings. Results show that most gun laws are unrelated to whether an event occurs. In addition, common state and federal gun laws that outlaw assault weapons are unrelated to the likelihood of an assault weapon being used during a public shooting event. Moreover, results show that the use of assault weapons is not related to more victims or fatalities than other types of guns. However, the use of hand guns, shot guns and high-capacity magazines is directly related to the number of victims and fatalities in a public shooting event. Finally, the gunman’s reported mental illness is often associated with an increase in the number of victims and fatalities.

KEYWORDS:

• Guns
• public shootings
• gun control
• gun laws

JEL CLASSIFICATION:

• K10
• K40

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

¹ http://www.nytimes.com/2012/12/17/us/politics/bloomberg-urges-obama-to-take-action-on-gun-control.html

² http://www.ncsl.org/research/civil-and-criminal-justice/summary-president-obama-gun-proposals.aspx

³ The Stanford Mass Shootings of America (MSA) data project, the Global Terrorism Database, a compiled data set by Follman, Aronson, and Pan (2012), and the Department of Justice’s study on active shooter incidence in the United States.

⁴ Serial Murder: A Multi-Disciplinary Perspective for Investigators. The Federal Bureau of Investigations. https://www.fbi.gov/stats-services/publications/serial-murder/serial-murder-july-2008-pdf.

⁵ The exception of a ‘single’ gunman is the case of the Columbine massacre and the Westside Middle School killings, both of which involved two shooters.

⁶ The gunman is excluded in the victim count.

⁷ A Study of Active Shooter Incidents in the United States between 2000 and 2013. The United States Department of Justice and the Federal Bureau of Investigation. https://www.fbi.gov/news/stories/2014/september/fbi-releases-study-on-active-shooter-incidents/pdfs/a-study-of-active-shooter-incidents-in-the-u.s.-between-2000-and-2013.

⁸ We note that results reported in this study are qualitatively similar when we exclude Washington D.C. and just use the 50 states.

⁹ Homicide in eight US cities: Trends, Context, and Policy Implications. National Institute of Justice, U.S. Department of Justice. https://www.ncjrs.gov/pdffiles1/ondcp/homicide_trends.pdf.

¹⁰ Handgun (27 CFR 478.11). (a) Any firearm which has a short stock and is designed to be held and fired by the use of a single hand; and (b) Any combination of parts from which a firearm described in paragraph (a) can be assembled.

¹¹ Revolver (27 CFR 478.11). A weapon originally designed, made, and intended to fire a projectile (bullet) from one or more barrels when held in one hand, and having (a) a chamber(s) as an integral part(s) of, or permanently aligned with, the bore(s); and (b) a short stock designed to be gripped by one hand and at an angle to and extending below the line of the bore(s).

¹² We use a linear probability model instead of a probit given the biases and inconsistency found in fixed effects estimators for non-linear models (see Greene 2004).

¹³ As a measure of robustness, we estimate Equation (3) using a different definition for assault weapons. Instead of the definition used for Assault Weapons according to FBI reports, we redefine Assault Weapons using a broader definition that has been used in a bill that was introduced 24 January 2013 that would impose various bans on assault weapons. Results from these tests again show that whether a gun that was used under this alternative definition is unrelated to the number of injured victims or the number of fatalities.

¹⁴ As another measure of robustness, instead of including an indicator variable for the use of high-capacity magazines, we include the number of guns that were used with high-capacity magazines. These unreported tests also show a direct relation between the number of guns with high-capacity magazines and the number of injured victims as well as the number of fatalities. The results from these tests are available upon request from the authors.

¹⁵ As mentioned in footnote 6, we use an alternative definition for assault weapons according to a bill voted on by the U.S. senate on 24 January 2013. Using this alternative definition for assault weapons, we are able to draw similar conclusions to those drawn in Table 6.

¹⁶ We also ran regressions where we interacted mental illness with our other variables such as age, minority status and venue. We did not find any significant interaction effects.