By Maia Szalavitz
When an act of seemingly inexplicable violence like the Arizona massacre occurs, everyone is desperate for explanations. Some look to political rhetoric, some look to mental illness, some blame the parents, others point to marijuana. But what’s really at fault?
The reality is clearly complex. As researchers searching for the causes of violence and the roots of psychosis know, Jared Loughner’s behavior cannot easily be explained by a gene or a drug or culture or parenting. While each of those factors can be shown to have measurable effects, their relative contributions are often small or moderate and can’t be easily teased apart into a recipe of rampage in any individual case.