A gunman opened fire in the New Castle County Courthouse in Wilmington, Del., on February 11, killing two women and injuring two police officers. Police shot and killed the man, identified as Thomas Matusiewicz, whose son may have been embroiled in a custody dispute with one of the victims, according to The News Journal in Wilmington.

This latest violent attack at a courthouse came about a week after Texas prosecutor Mark Hasse was gunned down and as President Obama and congressional leaders renewed the debate over gun control. Steven Swensen, a former U.S. marshal and founder of the Center for Judicial and Executive Security in Saint Paul, Minn., is working with the National Center for State Courts in assessing safety at courthouses across the nation.He talked to The National Law Journal about the shooting in Delaware—and about why violent incidents are increasing despite a renewed focus on safety.

The remarks below have been edited for length and clarity.

NLJ: This is the latest shooting to take place at or near a courthouse. In recent weeks, a local prosecutor in Kaufman County, Texas, was shot and killed as he walked to his car in the parking lot of the courthouse. In San Diego, an attorney’s client attacked him with a razor in the courtroom. Is there a surge in these incidents despite an increase in courthouse security over the past few years?

Swenson: From 2000 and 2009, we had 78 courthouse attacks, bombings and arson attacks. In the last three years, we had 38, so we’re averaging 13 a year now, which puts us on pace for 130 for this decade, which is almost a 40 percent increase in the last decade.

NLJ: What do you attribute this increase to?

Swenson: You’ve got the highly charged emotional events—the family court domestic situations where people feel backed into a corner and have triggering events. With certain groups, like antigovernment domestic extremists, there’s more of a forum to promote their causes and find people of like beliefs and ideologies. In the 1980s and ’90s it wasn’t as easy to do this. Now you go on the Internet and you find people with the same complaints and same issues you have.

NLJ: What’s your general reaction to the shooting in Delaware?

Swenson: I’m not really surprised. From what I know, it seems to involve a family court domestic situation. I’m not sure about the shooter’s criminal history, but in past incidents the persons involved in domestic violence in family courts don’t have a criminal record per se. So they’re not a traditional threat source, like street gangs, terrorists or criminals. Nontraditional threat sources are regular citizens who for whatever reason resort to this type of violence. Maybe it’s the last resort, or they’re pushed into a situation where they feel out of control and this is the way they respond—they lash out violently.

NLJ: Monday’s shooting occurred in the lobby area of the courthouse, with metal detectors and security personnel present. What else could have been done in a situation like that?

Swenson: The security screening system worked as designed: The person was prevented from getting in the courthouse and committing more violence. He stopped at the screening station and that’s where he was engaged. The security screening system is the O.K. Corral—because when setting up to detect weapons and prevent them from getting into the courthouse, you’ll encounter violent individuals. They realize they won’t be able to get any further, so that’s where they go ahead and start shooting.

What I promote—and what’s been promoted by the Secret Service during the 1990s and the U.S. marshals—is protective intelligence and threat management. What we do is identify threat sources. Through studies and research, we determine what are inappropriate communications or indicators of violent behavior. Inappropriate communications can be behavior, actions, words—spoken or written—that are potential pre-indicators of violent behaviors.In this situation, was there a restraining order or protection order? Previous acts of violence? Any threats made?

Most state and local agencies responsible for courthouse security don’t have a threat-management program, and that’s where we’re really lacking as far as identifying these threat sources before they commit violent acts. We may have court security officers, bailiffs, surveillance systems—but if you want to take the proactive approach, you want to go to contemporary risk management.

NLJ: Like many other shootings at courthouses, this appears to have involved a domestic dispute. Is it inherent that working in family law is more dangerous as a general rule?

Swenson: Law enforcement has put resources into physical security, making sure prisoners and traditional threat sources I talked about are secure. So we’re setting up security for high-threat trials—our motorcycle gangs, domestic terrorists and other criminals. Now we get into nontraditional threat sources, which in the family court we’ve seen some increase in incidences and it’s a result of what I labeled as highly charged emotional events. That’s why it’s really important when looking at these incidents as far as what we can do not just to deter and prevent, but identify individuals who have an enhanced threat risk.

Contact Amanda Bronstad at abronstad@alm.com.