Background In 2015, California passed AB 71 to create a state-wide Use of Force Incident Reporting Database (URSUS) to tabulate law enforcement-reported encounters that resulted in serious bodily injury, death or discharge of a firearm. We use these data to analyse encounters that resulted in fatal and non-fatal civilian injuries in California between 2016 and 2021.

Methods We performed a retrospective review of URSUS from January 2016 to December 2021. The main outcomes were the number of law enforcement encounters that involved civilian serious bodily injury or death and encounter-level characteristics.

Results URSUS recorded 3677 incidents between 2016 and 2021 resulting in 942 civilian fatalities and 2735 instances of serious civilian injuries. Injury rates were highest for civilians who identified as Hispanic (1.80 injuries per 100 000 population) or black (5.17 injuries per 100 000 population). Injuries involving a firearm were usually fatal (58.9% fatality rate; 1471 injuries), while non-firearm incidents were more likely to result in serious injuries (4.2% fatality rate; 2929 injuries). We did not find statistically significant trends in rates of civilian injuries per 100 000 population.

Conclusion Rates of law enforcement-related injuries were highest for Hispanic and black civilians in California between 2016 and 2021 and firearm-related injuries were overwhelmingly fatal. The URSUS database represents an important effort by law enforcement agencies to collect information on injuries and fatalities resulting from law enforcement encounters. Given similar databases exist in fewer than half of states, additional legislative efforts are needed to improve systematic national data collection on these encounters.