More than half of suicide deaths in the United States result from self-inflicted firearm injuries. Extreme risk protection order (ERPO) laws in 21 states and the District of Columbia temporarily limit access to firearms for individuals found in a civil court process to pose an imminent risk of harm to themselves or others. Research with large multistate study populations has been lacking to determine effectiveness of these laws. This study assembled records pertaining to 4,583 ERPO respondents in California, Connecticut, Maryland, and Washington. Matched records identified suicide decedents and self-injury method. Researchers applied case fatality rates for each suicide method to estimate nonfatal suicide attempts corresponding to observed deaths. Comparison of counterfactual to observed data patterns yielded estimates of the number of lives saved and number of ERPOs needed to avert one suicide. Estimates varied depending on the assumed probability that a gun owner who attempts suicide will use a gun. Two evidence-based approaches yielded estimates of 17 and 23 ERPOs needed to prevent one suicide. For the subset of 2,850 ERPO respondents with documented suicide concern, comparable estimates were 13 and 18, respectively. This study's findings add to growing evidence that ERPOs can be an effective and important suicide prevention tool.
Swanson et al. (Tue,) studied this question.