Criminologist Adam Lankford argues that suicide bombers are driven by psychological reasons, not just ideological ones – that is, they “kill themselves to escape crises or unbearable pain”:
[When] I began watching martyrdom videos and reading case studies, letters and diary entries, what I discovered was a litany of fear, failure, guilt, shame and rage. … [F]ar from being normal, these self-destructive killers have often suffered from serious mental trauma and always demonstrate at least a few behaviors on the continuum of suicidality, such as suicide ideation, a suicide plan or previous suicide attempts.
Along similar lines, Lankford recently analyzed 185 American mass killings to learn when and why shooters die at the scene of their crimes. Joshua Keating lays out some of his findings:
Thirty-eight percent of perpetrators of mass shootings commit suicide by their own hand and 48 percent die in the attacks. (Some of those extra 10 percent could probably also be categorized as “suicide by cop.”) Lankford also found that for each additional victim killed in the attack, the shooters’ likelihood of dying was 1.2 times higher. Shooters are also far more likely to die when they bring multiple weapons to the scene and when attacking factories or warehouses rather than schools and office buildings.
The Dish 