By Alaina De Biasi, Anthony A. Braga, Brad Velasquez & Garen Wintemute 

Background: Privately made firearms (PMFs) or “ghost guns” are homemade, unserialized, untraceable firearms that have been increasingly used in violent crime in the United States. Very little is known about the types of PMFs recovered by law enforcement agencies and the crimes associated with these recoveries. This lack of information limits effective violence prevention policies and practices. Comparative analysis of PMF recoveries in specific cities helps clarify whether local PMF patterns and characteristics vary or reflect more general trends. This research advances epidemiological understanding of emergent violent gun injury prevention challenges by identifying variations in recovered PMF types and use in violent, drug, and weapon-related offenses in Los Angeles and San Diego, California.

Methods: Conjunctive analysis of case configurations (CACC) identifies patterns among observations (i.e., case configurations) and calculates their probability associated with a given outcome. CACC was used to identify the most common types of PMFs recovered by the Los Angeles (LAPD) and San Diego (SDPD) police departments. For each department and offense type, case configurations with above-average probabilities of offense involvement were determined. Comparisons across departments were made to identify similarities and differences in PMF characteristics and usage.

Results: PMFs were more likely to be involved in violent and weapon-related offenses in Los Angles but more likely to be involved in drug-related offenses in San Diego. In both cities, the 9 mm Polymer 80 handgun was the dominant PMF. However, 9 mm handguns were most likely to be involved in weapon-related offenses in Los Angeles compared to 0.40 handguns in San Diego. Furthermore, large-caliber handguns tended to display above-average probabilities of involvement in violent and drug offenses in Los Angeles. Long guns were represented in case configurations with above-average probabilities of involvement in substantive crimes, including violence.

Conclusions: Comparative analyses of PMF recovery patterns in Los Angeles and San Diego reveal meaningful contextual variations in PMF characteristics and suggest intentional firearm type selections by offenders. The results support increased regulation of PMFs and highlight the importance of efforts to identify and disrupt the illicit supply of large-caliber PMF handguns and PMF long guns.

Injury Epidemiology volume 11, Article number: 17 (2024)

By James H. Burch II,  Stacey Clouse , Annelise M. Pietenpol

The Joyce Foundation commissioned the National Policing Institute (NPI) to assess and produce a report on mandatory reporting laws for lost and stolen firearms and how law enforcement agencies are currently using, enforcing, and encouraging compliance with such laws. This report supports the Joyce Foundation’s efforts to identify barriers and inform policymakers and law enforcement leaders on best practices related to the enforcement of reporting lost and stolen firearms. Across the nation, policymakers and law enforcement agencies have turned to different legal and policy approaches to address gun violence and the movement or “diversion” of firearms from the legal to the illegal market, where criminals and those who are prohibited by law from having firearms may obtain them. State laws mandating reporting of lost and stolen firearms are intended to address the issue of criminal access to firearms, yet very little is known about implementation best practices and challenges. This study, likely the first to assess implementation and design questions across the states, finds that changes are needed to realize much of the benefit these laws were intended to provide. Specifically, the results of this study suggest that: • Mandatory reporting laws for lost and stolen firearms may be designed or applied in ways that dilute their potential impact. • Some penalties may have limited or no potential for deterrence, may undermine the importance or significance of reporting or the law itself, and contribute to concerns over criminal justice fines and fees. • The laws appear to lack the necessary support of clear implementation approaches and input and support of state and local law enforcement. However, the study does not find that the laws serve no purpose or that they should be abolished or abandoned. Instead, the study proposes alternative approaches emphasizing incentives and behavioral change over punitive measures. It advocates for enhanced civil liability provisions and educational initiatives to promote awareness and compliance with reporting laws among firearm owners and sellers. Additionally, it underscores the effectiveness of targeted awareness campaigns and problem-oriented policing strategies in deterring firearm-related offenses such as straw purchasing. Furthermore, the study provides more than 20 recommendations to be considered by government and policy leaders, law enforcement, and communities. These recommendations include: • Reconsidering small or low penalties, such as fines, and considering alternatives, such as enhanced liability provisions and restrictions on future registrations and licensing (where applicable) that may be more powerful than the threat of fines for violators. • Consider the issue of intent in failures to report or lack of knowledge of the reporting requirement and consider offering liability protections in future civil action associated with the firearm’s loss or theft when timely reporting has occurred. • Requiring firearm sellers to provide notice of the mandatory reporting law, stipulate the information required for reporting, and establish responsibilities of law enforcement receiving reports of lost or stolen firearms. • Ensuring that national systems for sharing information on stolen and recovered firearms are utilized consistently. • Considering innovative programs, including state-level, publicly accessible, and searchable stolen firearms databases to allow prospective purchasers to ensure that the firearm they may be purchasing from a private seller has not been reported stolen and providing federal funding to support innovative approaches. • Review firearm recovery protocols for law enforcement to ensure that all recovered firearms are checked against the National Crime Information Center (NCIC) as soon as possible after recovery. • Improving training and outreach to law enforcement, firearm sellers, and owners to promote compliance with the law and ways of reducing theft, including safe storage requirements and guidance. • Prioritizing further research into firearm theft and mandatory reporting laws through additional or set-aside research funding from federal grant-making organizations.    

Arlington VA: National Policing Institute, 2024.   44p.

By Dennis Mares

This document is part of the Response Guide series which is one of three series in the Problem-Oriented Guides for Police series. Response guides summarize knowledge about whether police should use certain responses to address various crime and disorder problems, and about what effects they might expect. This guide include examples and case studies as it covers the basic principles of gunfire detection and how it works; discusses the efficacy and police uses of acoustic gunshot detection systems, describing types of systems, experimental applications of the technology, and accuracy of acoustic gunshot detection systems; describes the analysis of acoustic gunshot detection system data; recommends best practices for responding to gunshots; and gives advice for implementing acoustic gunshot detection system, noting considerations such as coverage area, costs, personnel needs, interoperability with other systems, training requirements, and other factors that may impact decision-making.

PROBLEM-ORIENTED GUIDES FOR POLICE RESPONSE GUIDE SERIES NO. 14 Tempe, AZ: ASU Center for Problem-Oriented Policing, 2022. 29p

By Daniel S. Lawrence, Nancy G. La Vigne, Paige S. Thompson

This publication represents a technical summary report of the Urban Institute’s evaluation of the implementation, use, and impact of Gunshot Detection Technology (GDT) by law enforcement agencies in three cities: Denver, CO; Milwaukee, WI; and Richmond, CA. The goal of this study was to conduct a rigorous process and impact evaluation of GDT to inform policing researchers and practitioners about the impact GDT may have. To achieve this goal, we implemented a mixed-methods research design. Qualitative data collection included 46 interviews with criminal justice stakeholders to learn implementation processes and challenges associated with iDT, and 6 focus groups with 49 community members to learn how residents feel about policing efforts to reduce firearm violence and its use of GDT. Quantitative data collection included administrative data on calls for service (CFS), crime, and GDT alerts, as well as comprehensive case file reviews of 174 crimes involving a firearm. Quantitative analyses examined the impact of GDT by (1) comparing counts of gunshot notifications for GDT alerts to shooting-related CFS, (2) comparing response times of GDT alerts to shooting-related CFS, (3) examining the impact GDT has had on CFS and crimes, and (4) conducting a cost-benefit analysis of the GDT. Evaluation findings suggest that GDT is generally but not consistently associated with faster response times and more evidence collection, with impact on crime more uneven but generally cost-beneficial. We also conclude that agencies should implement GDT sensors strategically, train officers thoroughly, ensure that GDT data are used and integrated with other systems, and engage with community members early and often. More detailed information from this study will be available in forthcoming journal articles.

Washington, DC: Urban Institute 2019. 15p.

by Lucy C. Sorensen, Montserrat Avila-Acosta, John Engberg, Shawn D. Bushway

U.S. public school students increasingly attend schools with sworn law enforcement officers present. Yet little is known about how these school resource officers (SROs) affect school environments or student outcomes. Our study uses a fuzzy regression discontinuity (RD) design with national school-level data from 2014 to 2018 to estimate the impacts of SRO placement. We construct this discontinuity based on the application scores for federal school-based policing grants of linked police agencies. We find that SROs effectively reduce some forms of violence in schools, but do not prevent gun-related incidents. We also find that SROs intensify the use of suspension, expulsion, police referral, and arrest of students. These increases in disciplinary and police actions are consistently largest for Black students, male students, and students with disabilities.''

By Josh Levine

The firearms debate in the United States often pits public health against freedom. This false dichotomy implies that gun laws, even wise ones, inherently erode individual liberty. Indeed, this appeal to liberty finds fertile ground in the United States, where many Americans intuitively reject any incursion on their freedom. Yet this one-sided conception of liberty is, at best, incomplete: while the government can certainly encroach on our freedom, so too can our fellow citizens.

A historically grounded conception of liberty in the United States includes the sense of security that fosters self-expression without fear of arbitrary constraint. That is, when citizens feel safe, they can properly exercise their will. But this tranquility doesn't exist naturally. To achieve it, the government must exercise a monopoly of force and ensure that citizens do not fear other citizens. Only then can people act and express themselves without fear of reprisal.

Yet when civilians openly wield their guns in public, they impose an arbitrary constraint on others that represses others' ability to exercise their will. Armed goers change the risk calculations for their fellow citizens—often forcing them to avoid areas where guns are present or arm themselves in self-defense. As this Note discusses, each of these options begets a compounding harm to our liberty. And the resulting proliferation of civilian defensive arms in the United States—the modern arms race—does not represent peace, only détente.

By this understanding, open carrying itself subverts liberty, and its regulation upholds it. Although an individual's arms may constitute a productive solution to his own fear, the externalities on others are substantial. The state must prevent these costs to the liberty of others by regulating those wielding firearms in public spaces.

18 Duke Journal of Constitutional Law & Public Policy Sidebar–265 (Arlington, VA: National Policing Institute 2022.

By Public Safety Canada

Public Safety Canada (“Public Safety”) launched an engagement process in October 2018 to help inform policy, regulations and legislation to reduce violent crime involving firearms. Through this engagement, Public Safety sought to engage and hear from a wide range of stakeholders, which included those both in support of and opposed to limiting access to handguns and assault-style firearms. While the engagement was framed by the examination of a potential ban, the discussion explored several potential measures to reduce violent crime. The engagement process included a series of eight in-person roundtables, an online questionnaire, a written submission process, and bilateral meetings with a range of stakeholders. Given the diversity of perspectives on this issue, this report highlights key common themes and ideas shared by participants, as well as unique and divergent views. The goal of this report is to accurately represent “what we heard” on this issue. Overall Key Findings  There are polarized views on a potential ban and limiting access: Overall, participants were strongly polarized on the issue of banning handguns and assault-style firearms. The stakeholder views expressed in two of the engagement channels - the in-person dialogues and written submissions - provided a variety of perspectives both opposed to and in support of a ban. In contrast, most questionnaire respondents (representing a self-selected group of Canadians) were opposed to a ban.  Target crime and focus on enforcement: Many participants felt strongly that a ban would target law-abiding owners, rather than illicit firearms, and would not greatly impact crime reduction (particularly gang violence). As a result, many called for enhanced enforcement capacity for law enforcement and border services, as well as harsher punishments for firearms trafficking and gun-related crime.  Address underlying causes of firearm violence: One point of consensus among the diverse perspectives is the need to address the socioeconomic conditions that can lead to gun violence, which requires more support for community-level programs and initiatives. These factors include poverty, a lack of education or employment opportunities, lack of mental health supports and social exclusion.  Collect and share relevant data on gun crime: There is a need to improve the ongoing collection and sharing of data on gun crime, particularly in terms of sources of illicit firearms and the types of crime being committed. It was expressed that data is critical for supporting law enforcement and border agencies efforts, as well as informing policy and legislation.  Willingness for collaboration with the firearms community/industry: Many stakeholders representing various aspects of the firearms community want the opportunity to be more engaged and to collaborate with the federal government to develop solutions on this issue.  Need a multi-faceted approach: A wide range of approaches and ideas were discussed, which suggests that a multifaceted approach is needed to address this issue – rather than implementing a ban in isolation.

Ottawa: Public Safety Canada, 2023. 34p.

By Anthony Louis D’Agostino, Mindy Hu, Naihobe Gonzalez, Natalie Larkin, and Michela Garber

Oakland Unite aims to interrupt and prevent violence by administering grants through a diverse set of strategies, which includes shooting and homicide response. Each year, this strategy provides $1.4 million in grants to community-based organizations that in turn offer services to hundreds of individuals. Grantees support two groups affected by gun violence: (1) those who have been the victim of gun violence or serious assault, and (2), those who have lost a loved one to gun violence. Grantees aim to address the immediate needs of shooting victims and their families; provide longer-term supports as the victims recover from injury or loss; and prevent retaliatory violence. Oakland Unite convenes and coordinates the network of providers and serves as the liaison between the network and law enforcement. The Oakland Unite 2019–2020 strategy evaluation report provides an in-depth analysis of the implementation of the four shooting and homicide response programs (summarized below), and the outcomes of participants over the 2016–2019 period. The evaluation’s findings suggest that shooting and homicide response offers needed supports to victims of violence and contributes to reducing re-injury and retaliation following a violent incident. As a single shooting injury can cost the city more than $1 million, the investment in these services has the potential to save the city considerable spending in the long run.

Oakland, CA: Mathematica, 2020. 109p.

By Anthony A. Braga, Philip J. Cook, and Stephen Douglas

The police have the unique capacity to preempt and deter violence and to reduce the use of firearms in violent encounters. But overly aggressive policing tactics have contributed to a fraught relationship with low-income minority communities in which gun violence is heavily concentrated. Increased resources should be devoted to policing gun violence, but efforts of this sort must be targeted and disciplined. Effective policing requires a focus on the places and people that are at greatest risk; and there is a strong case for police agencies to increase the resources devoted to investigations of all criminal shootings, not just homicides. Successful policing of gun violence requires a productive working relationship with victims and their neighbors, which can be facilitated through observing community policing principles and respect for residents’ interests.

The ANNALS of the American Academy of Political and Social ScienceVolume 704, Issue 1, November 2022, Pages 158-180.

By U.S. Department of Homeland Security

An Active Shooter is an individual actively engaged in killing or attempting to kill people in a confined and populated area; in most cases, active shooters use firearms(s) and there is no pattern or method to their selection of victims. Active shooter situations are unpredictable and evolve quickly. Typically, the immediate deployment of law enforcement is required to stop the shooting and mitigate harm to victims. Because active shooter situations are often over within 10 to 15 minutes, before law enforcement arrives on the scene, individuals must be prepared both mentally and physically to deal with an active shooter situation.

Washington, DC: US Department of Homeland Security, 2008 13p.

By Small Arms Survey

As demonstrated in the Samll Arms Survey 2010, addressing the factors that trigger conflicts and fuel gang vioence has a much more lasting---and constructive---impact than simply incarcerating or marginalizing members of street gangs and armed groups.' Executive Director, United Nations Office on Drugs and Crime. `The Small Arms Survey 2010 provides further evidence that efforts to address gangs and gangs violence must encompass a wide range of measures---including not only targeted law enforcement tactics and illicit gun interdiction, but also prevention and youth development initiatives. In the long term, we must address the factors that lead young people to join gangs in the first place.'

Cambridge, UK: Cambridge University Press, 2010. 352p.

By Philp Alpers

In New Zealand, 250,000 licensed shooters own an estimated 1.1 million firearms, enough for one in each occupied dwelling and sufficient to outnumber the combined small-arms of the police and armed forces by a ratio of 30 to 1. We own 11 times as many guns per capita as the English and the Welsh, 60% more than the Australians but less than half as many as the residents of the United States. An additional 14,000 guns are imported to New Zealand in a typical year. Any New Zealander with a basic firearms licence may legally buy and keep any number of sporting rifles and shotguns in any home without any official records of the guns being kept anywhere. Police have no statutory authority to monitor the size and content of such a gun owner’s collection. Each day an average of seven firearm offences involving danger to life are reported to the police, while one in five homicides are committed with a firearm. In a typical year 91 New Zealanders are shot to death: one for every four days. Of these, 75% are suicides, 12% accidents, 11% homicides, while in 2% of cases the cause is undetermined. In an average year, 13 children aged 15 or younger die from gunshot wounds. Our gun death toll is 10% higher than the toll from cervical cancer. For every ten New Zealanders who die from HIV/AIDS, fifteen die by gunshot. Gun death is three times more common than death by fire. In addition to gun killings, non-fatal gun injuries result in one New Zealander being hospitalised on average every four days. Of all victims of gun homicide in this country during 1992-94, most (52.5%) were shot by a licensed gun owner. Almost all victims (95%) were killed by a familiar male. Half were shot by their partner, an estranged partner or a member of their own family. Of the perpetrators, 82% had no previous history of violent crime, while none had a history of mental illness.

Wellington, NZ: New Zealand Police Association, 1996. 38p.