Mr. B, age 37, presents to a community mental health center for an appointment following a recent emergency department visit. He is diagnosed with schizophrenia, and has been treated for approximately 1 year. Six months ago, Mr. B stopped taking his antipsychotic due to its adverse effects. Despite compliance with another agent, he has become increasingly disorganized and paranoid.
He now believes that his mother, with whom he has lived all his life and who serves as his guardian, is poisoning his food and trying to kill him. She is an employee at a local grocery store, and Mr. B has expressed concern that her coworkers are assisting her in the plot to kill him.
Following a home visit, Mr. B’s case manager indicates that the patient showed them the collection of weapons he is amassing to “defend” himself. This leads to a concern for the safety of the patient, his mother, and others.
Although parricide—killing one’s parent—is a relatively rare event, its sensationalistic nature has long captured the attention of headline writers and the general public. This article discusses the diagnostic and demographic factors that may be seen among individuals who kill their parents, with an emphasis on those who commit matricide (murder of one’s mother) and associated spree killings, where an individual kills multiple people within a single brief but contiguous time period. Understanding these characteristics can help clinicians identify and more safely manage patients who may be at risk of harming their parents in addition to others.
Characteristics of perpetrators of parricide
Worldwide, approximately 2% to 4% of homicides involve parricide, or killing one’s parent.1,2 Most offenders are men in early adulthood, though a proportion are adolescents and some are women.1,3 They are often single, unemployed, and live with the parent prior to the killing.1 Patricide occurs more frequently than matricide.4 In the United States, approximately 150 fathers and 100 mothers are killed by their child each year.5
In a study of all homicides in England and Wales between 1997 and 2014, two-thirds of parricide offenders had previously been diagnosed with a mental disorder.1 One-third were diagnosed with schizophrenia.1 In a Canadian study focusing on 43 adult perpetrators found not criminally responsible,6 most were experiencing psychotic symptoms at the time of parricide; symptoms of a personality disorder were the second-most prevalent symptoms. Similarly, Bourget et al4 studied Canadian coroner records for 64 parents killed by their children. Of the children involved in those parricides, 15% attempted suicide after the killing. Two-thirds of the male offenders evidenced delusional thinking, and/or excessive violence (overkill) was common. Some cases (16%) followed an argument, and some of those perpetrators were intoxicated or psychotic. From our clinical experience, when there are identifiable nonpsychotic triggers, they often can be small things such as an argument over food, smoking, or video games. Often, the perpetrator was financially dependent on their parents and were “trapped in a difficult/hostile/dependence/love relationship” with that parent.6 Adolescent males who kill their parents may not have psychosis7; however, they may be victims of longstanding serious abuse at the hands of their parents. These perpetrators often express relief rather than remorse after committing murder.
Three categories to classify the perpetrators of parricide have been proposed: severely abused, severely mentally ill, and “dangerously antisocial.”3 While severe mental illness was most common in adult defendants, severe abuse was most common in adolescent offenders. There may be significant commonalities between adolescent and adult perpetrators. A more recent latent class analysis by Bojanic et al1 indicated 3 unique types of parricide offenders (Table 1).
Continue to: Matricide: A closer look...