Public Mass Shooters and the Prevalence of Suicidality.

It is well documented that over a third of public mass shooters die by suicide. However, the rate of suicidality among public mass shooters during their attacks may be greater. Using the notion of a final act mentality, we operationalize suicidality as not only intentionally ending one's life but also as accepting that committing the act will end one's life as they know it. To assess the rate of suicidality in public mass shooters, we analyze publicly available data on plans to avoid capture, initial outcomes post-attack, and suicidal capability for 54 offenders who killed six or more people between January 1, 2000, and May 6, 2023. Our findings indicate that nearly all public mass shooters were suicidal at the time of the attack. Although based on a small sample, we found no statistically significant difference in suicidal capability between those who lived versus those who died by suicide.