Gender differences exist in the workplace, medical schools, and in health care, so why should murder be any different?

Prior studies have shown that men and women who kill do so for different reasons and in different environments. But a group of Swedish researchers found that this data depended mainly on male offenders. So they conducted a study to learn more about this underreported phenomenon and report on overall homicide trends.

They analyzed cases recorded by the Swedish National Council for Crime Prevention from 1990 to 2010 to compare the characteristics of murderous men and women. They looked at intentional acts of violence by one or more human beings resulting in death including murder, voluntary manslaughter, assault, and infanticide.

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Of the 1,570 homicide offenders, 90 percent were men and 10 percent were women, a ratio that held steady throughout the study period. Researchers found that women in a relationship were more likely than men to commit manslaughter and infanticide, and to be motivated by a severe mental disorder at the time of their crime. They also predominantly targeted intimate partners and family members. As for weapons, they were also more likely to resort to sharp-edged and pointed weapons like knives. Men, on the other hand, were more likely than women to commit murder or involuntary manslaughter against acquaintances and strangers and preferred using blunt violence, firearms, strangulation, and drowning. While women were more likely to commit deadly violence in a home, men tended to act in public places.

Both men and women were commonly under the influence of drugs or alcohol at the time of their offenses against adults, but not in the cases of child homicide — a finding the researchers believe deserves more attention. In fact, when looking at child killings, researchers found there were fewer differences between men and women.

That said, homicide in Sweden declined during the study period to one of the lowest homicide rates in the world. But since they were able to find differences between male and female offenders, the researchers believe their findings support previous notions that commonly held views of violence risk factors are more valid for men than for women. Additional tools and procedures for assessing risk in women are needed, they said.

Most homicidal women targeted men they were intimate with, which points to the problem of domestic abuse — physical, sexual, and psychological attacks most commonly seen in current or former partners that vary in frequency and severity. Certain groups of women see higher rates than others, but in all cases it’s a public health problem.

The present study concludes that a more thorough investigation of gender-related homicide patterns will ultimately help to “identify critical situations working as precursors of homicide that could be used to develop preventive action.”

Source: Tragardh K, Nilsson T, Granath S, Surup J. A Time Trend Study of Swedish Male and Female Homicide Offenders from 1990 to 2010. International Journal of Forensic Mental Health. 2016.