Socially proximate firearm violence across the life course: a population-based study of California adults

Background The effects of firearm violence extend beyond those who are directly injured, affecting families, friends, and communities through experiences such as knowing someone who has been shot. Although indirect exposure to firearm violence has been associated with adverse health outcomes, less is known about the prevalence, timing, and cumulative burden of socially proximate firearm violence exposure across the life course. Findings We analyzed data from the 2024 California Safety and Wellbeing Survey, a probability-based survey of California adults ( N = 3,531). Overall, 20.7% (95% confidence interval [CI] = 18.8–22.8) reported personally knowing someone who had been intentionally shot, representing an estimated 6.3 million California adults. Median age at first exposure was 19 years (interquartile range = 13–27), and more than half of exposed respondents reported knowing multiple people who had been shot. By age 45, cumulative exposure reached 51.3% (95% CI: 40.9–63.2) among Black individuals, 22.9% (95% CI = 19.2–26.6) among Latino/a/x individuals, and 17.9% (95% CI = 15.1–20.8) among White individuals. Compared with White individuals, Black (hazard ratio = 3.85, 95% CI = 2.64–5.62) and Latino/a/x (hazard ratio = 1.42, 95% CI = 1.10–1.83) individuals experienced significantly higher hazards of exposure. Conclusions Socially proximate firearm violence is a common life-course experience that often begins during adolescence. These findings provide the first population-based estimates of its timing and cumulative burden, establish a foundation for surveillance and future research on the population health consequences of broader experiences of firearm violence, and can inform developmentally and culturally responsive early intervention and trauma recovery efforts.