Article

Officer-Involved Shootings and Concealed Carry Weapons Permitting Laws: Analysis of Gun Violence Archive Data, 2014–2020

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Abstract

About 1,000 civilians are killed every year by a law enforcement officer in the USA, more than 90% by firearms. Most civilians who are shot are armed with a firearms. Higher rates of officer-involved shootings (OIS) are positively associated with state-level firearm ownership. Laws relaxing restrictions on civilians carrying concealed firearms (CCW) have been associated with increased violent crime. This study examines associations between CCW laws and OIS. We accessed counts of fatal and nonfatal OIS from the Gun Violence Archive (GVA) from 2014–2020 and calculated rates using population estimates. We conducted legal research to identify passage years of CCW laws. We used an augmented synthetic control models with fixed effects to estimate the effect of Permitless CCW law adoption on OIS over fourteen biannual semesters. We calculated an inverse variance weighted average of the overall effect. On average, Permitless CCW adopting states saw a 12.9% increase in the OIS victimization rate or an additional 4 OIS victimizations per year, compared to what would have happened had law adoption not occurred. Lax laws regulating civilian carrying of concealed firearms were associated with higher incidence of OIS. The increase in concealed gun carrying frequency associated with these laws may influence the perceived threat of danger faced by law enforcement. This could contribute to higher rates of OIS.

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Objectives: To estimate the risk of mortality from police homicide by race/ethnicity and place in the United States. Methods: We used novel data on police-involved fatalities and Bayesian models to estimate mortality risk for Black, Latino, and White men for all US counties by Census division and metropolitan area type. Results: Police kill, on average, 2.8 men per day. Police were responsible for about 8% of all homicides with adult male victims between 2012 and 2018. Black men's mortality risk is between 1.9 and 2.4 deaths per 100 000 per year, Latino risk is between 0.8 and 1.2, and White risk is between 0.6 and 0.7. Conclusions: Police homicide risk is higher than suggested by official data. Black and Latino men are at higher risk for death than are White men, and these disparities vary markedly across place. Public Health Implications. Homicide reduction efforts should consider interventions to reduce the use of lethal force by police. Efforts to address unequal police violence should target places with high mortality risk. (Am J Public Health. Published online ahead of print July 19, 2018: e1-e8. doi:10.2105/AJPH.2018.304559).
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Laws related to the sale, use, and carrying of firearms have been associated with differences in firearm homicide rates at the state level. Right-to-carry (RTC) and stand your ground (SYG) laws are associated with increases in firearm homicide; permit-to-purchase (PTP) laws and those prohibiting individuals convicted of violent misdemeanors (VM) have been associated with decreases in firearm homicide. Evidence for the effect of comprehensive background checks (CBC) not tied to PTP is inconclusive. Because firearm homicide tends to concentrate in urban areas, this study was designed to test the effects of firearm laws on homicide in large, urban U.S. counties. We conducted a longitudinal study using an interrupted time series design to evaluate the effect of firearm laws on homicide in large, urban U.S. counties from 1984 to 2015 (N = 136). We used mixed effects Poisson regression models with random intercepts for counties and year fixed effects to account for national trends. Models also included county and state characteristics associated with violence. Homicide was stratified by firearm versus all other methods to test for specificity of the laws’ effects. PTP laws were associated with a 14% reduction in firearm homicide in large, urban counties (IRR = 0.86, 95% CI 0.82–0.90). CBC-only, SYG, RTC, and VM laws were all associated with increases in firearm homicide. None of the laws were associated with differences in non-firearm homicide rates. These findings are consistent with prior research at the state level showing PTP laws are associated with decreased firearm homicide. Testing the effects of PTP laws specifically in large, urban counties strengthens available evidence by isolating the effects in the geographic locations in which firearm homicides concentrate.
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Objectives: To determine the frequency of loaded handgun carrying among US adult handgun owners, characterize those who carry, and examine concealed carrying by state concealed carry laws. Methods: Using a nationally representative survey of US adults in 2015, we asked handgun owners (n = 1444) about their past-30-day carrying behavior. Results: Among surveyed handgun owners, 24% (95% confidence interval[CI] = 21%, 26%) carried loaded handguns monthly, of whom 35% (95% CI = 29%, 41%) did so daily; 82% (95% CI = 77%, 86%) carried primarily for protection. The proportion of handgun owners who carried concealed loaded handguns in the past 30 days was 21% (95% CI = 12%, 35%) in unrestricted states, 25% (95% CI = 21%, 29%) in shall issue-no discretion states, 20% (95% CI = 16%, 24%) in shall issue-limited discretion states, and 9% (95% CI = 6%, 15%) in may-issue states. Conclusions: We estimate that 9 million US adult handgun owners carry loaded handguns monthly, 3 million do so every day, and most report protection as the main carrying reason. Proportionally fewer handgun owners carry concealed loaded handguns in states that allow issuing authorities substantial discretion in granting carrying permits. (Am J Public Health. Published online ahead of print October 19, 2017: e1-e7. doi:10.2105/AJPH.2017.304072).
Article
Researchers have yet to explore the validity of “unofficial” media-driven and crowdsourced police-involved killings data. This omission is important because unofficial data are touted as providing accurate counts and narratives pertaining to officer-involved shootings—at least relative to official data. To address this shortcoming, we compared the incidence of and details surrounding officer-involved killings in three unofficial datasets (FatalEncounters.org, Deadspin, and the Washington Post) to officially collected data on officer-involved shootings from the city of Dallas. Reporting on the incidence of officer-involved killings was mostly consistent across data sources. Incident details varied across data sources, however, especially with respect to investigation outcomes.
Article
In a seminal paper Abadie, Diamond, and Hainmueller [2010] (ADH) develop the synthetic control procedure for estimating the effect of a treatment, in the presence of a single treated unit and a number of control units, with pre-treatment outcomes observed for all units. The method constructs a set of weights such that covariates and pre-treatment outcomes of the treated unit are approximately matched by a weighted average of control units. The weights are restricted to be nonnegative and sum to one, which allows the procedure to obtain the weights even when the number of lagged outcomes is modest relative to the number of control units, a setting that is not uncommon in applications. In the current paper we propose a more general class of synthetic control estimators that allows researchers to relax some of the restrictions in the ADH method. We allow the weights to be negative, do not necessarily restrict the sum of the weights, and allow for a permanent additive difference between the treated unit and the controls, similar to difference-in-difference procedures. The weights directly minimize the distance between the lagged outcomes for the treated and the control units, using regularization methods to deal with a potentially large number of possible control units.
Article
Objective: To evaluate the impact of state-level policy changes on assaults on law enforcement officers (LEOs) in the USA. Methods: Pooled time series and cross-sections with negative binomial regression were used to estimate the impact of state-level changes of right-to-carry (RTC), three-strikes and permit-to-purchase (PTP) handgun laws on fatal and non-fatal assaults of LEOs. LEO assaults were stratified by weapon type (all methods, handgun and non-handgun) and whether or not the assault was fatal. Data were collected from the Federal Bureau of Investigation's Law Enforcement Officers Killed and Assaulted database and analysed for the period 1984-2013 for fatal assaults and 1998-2013 for non-fatal assaults. Results: RTC laws showed no association with fatal (p>0.4) or non-fatal (p>0.15) assaults on LEOs. Three-strikes laws were associated with a 33% increase in the risk of fatal assaults on LEOs. Connecticut's PTP law was not associated with fatal (p>0.16) or non-fatal (p>0.13) assaults. Missouri's repeal of its PTP legislation was marginally associated with a twofold increased risk of non-fatal handgun assaults (p=0.089). Conclusions: This research indicates that three-strikes laws increase the risk of fatal assaults. RTC laws are not associated with increased risk of assault. Missouri's PTP repeal may increase the risk of non-fatal handgun assaults.
Article
This analysis provides tentative answers to three central questions about the adequacy of current measurement of homicide by police officers in the United States. First, it suggests that the national incidence of police homicide is substantially underreported, possibly by around 50 percent and that the police may account for closer to 3.6 percent of all homicides rather than to 1.8 percent, as previously had been reported. Second, the analysis reveals many instances in which the Vital Statistics data and data from other sources on the number of police homicides in specific cities are in substantial disagreement. This finding suggests the conclusion that none of the available data sources should be used to compare police homicide rates from one particular city of another. Judging from the similarity of the correlations of police homicide rates derived from the Vital Statistics and from alternate data sources with theoretically relevant independent variables, both of these data sources seem to be producing the same total patterns of variation across cities. A more useful response would be for all institutions concerned to improve the quality of their data. If the National Center for Health Statistics, the United States Public Health Service, and the American Association for Vital Records and Public Health Statistics revised the Standard Death Certificate to include a check box for police homicide; if the National Center for Health Statistics compiled mortality data by city of occurrence rather than by decedent's city of residence; if police departments published in their annual reports the number of citizens they killed each year; if the Uniform Crime Statistics published the numbers of citizens killed as reported in the supplmental homicide reports supplied by local police departments; and if all state legislatures required local police departments to file a report with a state agency whenever a citizen is killed, it would be much easier to monitor trends and differences in the use and possible abuse of police power.
Article
We discuss several nonparametric methods for attaching a standard error to a point estimate: the jackknife, the bootstrap, half-sampling, subsampling, balanced repeated replications, the infinitesimal jackknife, influence function techniques and the delta method. The last three methods are shown to be identical. All the methods derive from the same basic idea, which is also the idea underlying the common parametric methods. Extended numerical comparisons are made for the special case of the correlation coefficient.
Article
Bayesian empirical approaches appear frequently in fields such as egineering, computer science, political science and medicine, but almost never in law. This article illustrates how such approaches might be very useful in empirical legal studies. In particular, Bayesian approaches enable a much more natural connection between the normative or positive issues that typically motivate such studies and the empirical results.
Article
This article investigates the economic effects of conflict, using the terrorist conflict in the Basque Country as a case study. We find that, after the outbreak of terrorism in the late 1960's, per capita GDP in the Basque Country declined about 10 percentage points relative to a synthetic control region without terrorism. In addition, we use the 1998-1999 truce as a natural experiment. We find that stocks of firms with a significant part of their business in the Basque Country showed a positive relative performance when truce became credible, and a negative relative performance at the end of the cease-fire.
Comparative politics and the synthetic control method
  • A Abadie
  • A Diamond
  • J Hainmueller
The Counted: people killed by police in the United States - interactive. the Guardian
  • J Swaine
  • O Laughland
  • J Lartey
Effects of concealed-carry laws on violent crime
  • R Smart
Augsynth: the augmented synthetic control method
  • E Ben-Michael