Your book focuses on behavioral threat assessment — getting people to recognize possible warning signs, which you say are commonplace before a shooting like this week’s, and then intervening before tragedy happens. We know the Texas shoote exhibited plenty of alarming behavior, and that he had a very troubled home life. What would a successful implementation of threat assessment have looked like in this case?

An important part of the mission of threat assessment is to raise community awareness of the warning signs that lead to targeted violence, and to cultivate trust in this method for dealing with it. People need to have a sense of where they can turn for help. If you have a threat assessment team in place, experts in mental health, law enforcement, and education work together to evaluate specific cases of concern. They make a plan to intervene and use constructive measures to get the person off of what the field threat assessment calls the pathway fo violence. The way they do that is by gathering information from people around the offender — that’s where these warning behaviors become important, because they learn about those threatening comments, they learn about patterns of aggression that have gone on in the home, in the school, elsewhere. They then evaluate the level of danger, and determine the best way to intervene constructively with the person who is causing concern. That’s how most of the threat cases begin, when somebody speaks up because they’re worried or anxious about the way someone’s behaving.