Men, experts said, are often driven to murder their families by intense feelings of shame resulting from a job loss or a perceived inability to provide for family members.
Forensic psychologists and criminologist said, however, that these murderers do not simply "snap" but usually have long histories of mental illness.
Men and women who kill their children, forensic psychologists told ABC News, tend to be severally depressed or psychotic.
Women are more likely to kill their children than men are, but men are more likely to kill both their children and their spouse, said Dr. John Bradford, head of the forensic psychiatry department at the University of Ottawa.
Police investigating the deaths of Kevin Morrissey and his family said they found a note in which the 51-year-old father of two said he was distressed over the family's financial situation.
Morissey ran a skin care clinic with his wife, Dr. Mamiko Kawai, 40. The couple's two daughters were Nikki Morrissey, 8, and Kim Morrissey, 6.
Dr. Phillip Resnick, a psychiatry professor at Case Western Reserve University, said Morrissey may have been "severely depressed and believed his family was similarly miserable. He was ending the entire family's pain."
"Money is often an issue. The man sees himself as a breadwinner and may feel like he has to take the whole family out with him," Resnick said."
Murderous Mothers
Experts said that women are often motivated to kill their children for different reasons than men are.
Rather than feeling they have failed to adequately provide for their kids,
women often kill their children out of a delusional sense of altruism.
Women often fail at committing suicide, said Resnick, and their crimes are therefore less likely to be classified as familicide.
"Women try three times as often to commit suicide, but men are three times more successful," he said.
Psychosis
and severe depression can lead women to believe they are killing their children to end their suffering or because they believe they are demonically possessed.
"When you're psychotically depressed the whole world appears as if you're looking through dull gray glass. When you look at your children, you see them through your own suffering and emotional pain and believe they, too, are suffering. You begin to think they and you would be better off in heaven. This is
an altruistic delusion. The results are horrific, but it's done in the hopes of stopping suffering," said Bradford at the University of Ottawa.
https://abcnews.go.com/US/story?id=3307902