A study of firearm homicide and suicide rates in the 10 years after California simultaneously mandated comprehensive background checks (CBC) for nearly all firearm sales and a prohibition on gun purchase and possession via misdemeanors violence policies (MVP) for persons convicted of most violent misdemeanor crimes found no change in the rates of either cause of death from firearms through 2000.
California’s comprehensive background check and misdemeanor violence prohibition policies and firearm mortality
Annals of Epidemiology, October 2018
Received 10 July 2018, Accepted 3 October 2018, Available online 11 October 2018
“California’s comprehensive background check and misdemeanor violence prohibition policies and firearm mortality” was published in the October issue of the journal Annals of Epidemiology and conducted by the Violence Prevention Research Program (VPRP) at UC Davis and the Johns Hopkins Bloomberg School of Public Health. It compared observed annual firearm homicide and suicide rates in California over a decade following enactment of comprehensive background check and misdemeanor violence prohibition policies in 1991 with data from 32 control states that did not have similar policies in place during the same period.
“In the 10 years after policy implementation, firearm suicide rates were, on average, 10.9 percent lower in California than expected, but we observed a similar decrease in non-firearm suicide,” said Garen Wintemute, professor of emergency medicine and director of the Violence Prevention Research Program at UC Davis, senior author on the study.
This was a quasi-experimental ecological study using the synthetic control group methodology. The researchers included annual firearm and nonfirearm mortality data for California and 32 control states for 1981-2000, with secondary analyses up to 2005. The study found no net difference between firearm-related homicide rates before and during the 10 years after policy implementation and that the enacted background check and misdemeanor violence policies were not associated with changes in firearm homicides in California while changes in firearm suicides were similar to changes in nonfirearm suicides. The null findings in California with these policies were found consistent with other recent background check evaluations. Results were robust across multiple model specifications and methods.
From the study’s Abstract, “In 1991, California implemented a law that mandated a background check for all firearm purchases with limited exceptions (comprehensive background check or CBC policy) and prohibited firearm purchase and possession for persons convicted within the past 10 years of certain violent crimes classified as misdemeanors (MVP policy). We evaluated the population effect of the simultaneous implementation of CBC and MVP policies in California on firearm homicide and suicide.” Stated Conclusions and Results were, “CBC and MVP policies were not associated with changes in firearm suicide or homicide.”
The study’s lead author was Alvaro Castillo-Carniglia, at the time a postdoctoral scholar at VPRP. Other authors include Magdalena Cerdá from the Violence Prevention Research Program at the University of California, Davis, School of Medicine; and Jon S. Vernick, Daniel Webster and Cassandra Crifasi from the Center for Gun Policy and Research at Johns Hopkins Bloomberg School of Public Health. The authors and the journal reported there were no potential conflicts of interest relevant to the study.
Read more in the March 2019 issue.