Northwestern study looks at domestic murderers

As domestic violence-related killings continue to grab headlines, new research from Northwestern University’s Feinberg School of Medicine could help identify domestic abusers who are likely to suddenly murder a family member or partner.

The paper focuses on what differences in mental health, intelligence and background killers of their intimate partners have from people who murder an acquaintance or stranger. It specifically examined domestic killers who acted spontaneously – not those who planned the murder ahead of time.

Over a period of years, Northwestern researcher Robert Hanlon spent 1,500 hours conducting forensic evaluations of more than 150 men and women charged or convicted of first-degree murder. More than 100 of them were held at Cook County Jail.

“The domestic murderers were at a much, much higher rate of psychotic mental illness than the non-domestic murderers,” said Hanlon, an associate professor in psychiatry and behavioral sciences at the medical school.

“In addition to that, the domestic murderers tended to be lower intelligence, compared to the other group,” Hanlon said.

Killers of intimate partners and family members were also more likely to have been prescribed an antipsychotic or an antidepressant than the other killers, according to the paper, which was released last week.

They also were “marginally less likely to have a history of prior felony convictions,” the researchers wrote.

Research has already shown that certain factors, like whether there is a gun in the home, or if the abuser has ever choked their victim, indicate a higher risk of domestic homicide in an abusive relationship. Chicago Police are asking these questions when they respond to domestic situations as part of a pilot program in two police districts that hopes to identify domestic violence victims most at risk.

“Our hope is this will continue to draw more attention to these issues, and be able to educate people and make them more aware of risks that do exist,” Hanlon said.

Kathleen Doherty, executive director of the Chicago Metropolitan Battered Women’s Network, said she thought the research could be used as part of an intervention treatment plan for an abuser.

Not all domestic murders get media attention, however.

More than 30 percent of women murdered in 2012 were killed by their husbands or boyfriends, according to the paper. And more than 20 percent of women will experience some type of domestic violence in their lifetime.

If a member of a family has severe psychotic mental illness and a history of violence, and “particularly if they are non compliant with their treatment, then you start to really significantly increase the risk that that individual may act out violently,” Hanlon said.

And a partner or family member is “the easiest and most direct person to be a victim of that violence,” Hanlon said.