Humanities › Issues Psychology of Adolescent Parricide Teenagers Who Kill Their Parents Share Flipboard Email Print Ted Soqui/Getty Images Issues Crime & Punishment Criminals & Crimes Basics Prevention & Safety Investigations & Trials Serial Killers The U. S. Government U.S. Foreign Policy U.S. Liberal Politics U.S. Conservative Politics Women's Issues Civil Liberties The Middle East Terrorism Race Relations Immigration Animal Rights Canadian Government View More By Charles Montaldo Private Investigator Charles Montaldo is a writer and former licensed private detective who worked with law enforcement and insurance firms investigating crime and fraud. our editorial process Charles Montaldo Updated May 06, 2019 In the United States legal system, parricide is defined as the killing of a close relative, usually a parent. The crime encompasses matricide, the killing of one’s mother, and patricide, the killing of one’s father. It may also be part of a familicide, the killing of one’s entire family. Parricide is extremely rare, representing just 1 percent of all homicides in the United States in which the victim-offender relationship is known. The majority of parricides are committed by adults, with just 25 percent of patricides and 17 percent of matricides committed by persons 18 years and under, according to a 25-year study of parricides in the United States. However rare, adolescent parricide has become a distinct area of study by criminologists and psychologists due to the unpredictability and complexity of these crimes. Those who study these unique crimes tend to look closely at issues like domestic violence, substance abuse, and adolescent mental health. Risk Factors Due to the statistical improbability of adolescent parricide, this crime is virtually impossible to predict. However, there are factors that may increase the risk of patricide. They include domestic violence, substance abuse in the home, the presence of severe mental illness or psychopathy in an adolescent, and the availability of firearms in the home. However, none of these factors indicates that parricide is likely to occur. Even severe child abuse or neglect cannot be used as a predictor of a child acting violently against their abuser. The overwhelming majority of abused adolescents do not commit parricide. Types of Offenders In her book “The Phenomenon of Parricide,” Kathleen M. Heide outlines three types of parricide offenders: the severely abused, the dangerously antisocial, and the severely mentally ill. Severely abused: The most common type of adolescent offender commits patricide as a way of ending a cycle of abuse that has lasted many years. They have often reached out to others for help and/or sought other means to end the violence and been unsuccessful. Feeling powerless and overwhelmed, these adolescents kill their parents as a “last resort.” PTSD and depression are common in these cases.Dangerously antisocial: Dangerously antisocial individuals kill their parents because they see them as an obstacle to a goal or desire, such as money or freedom from rules. Typically, these adolescents exhibit antisocial characteristics, such as harming people and animals and destroying property, in early childhood. They may be diagnosed with or exhibit traits of Oppositional Defiant Disorder or Antisocial Personality Disorder, making them much more likely than those in the first category to re-offend.Severely mentally ill: These individuals have histories of severe mental illness, such as psychopathy or severe depression. They may experience delusions or hallucinations that lead them to kill their parents. Compared with adults, adolescents who commit parricide are less likely to show the clinical symptoms of a psychiatric disorder. Although most adolescents who commit parricide fit into one of these groups, categorizing them is not as easy as it might seem and requires in-depth evaluation by an experienced mental health professional. The Use of Firearms The majority of adolescents who kill their parents use a gun. In the 25-year study mentioned previously, handguns, rifles, and shotguns were used in 62 percent of patricides and 23 percent of matricides. However, adolescents were significantly more likely (57-80%) to use a firearm to kill a parent. A gun was the murder weapon in all seven cases Kathleen M. Heide examined in her study of adolescent patricide. Notable Cases of Parricide There have been several high profile cases of parricide in the United State over the last fifty years. Lyle and Erik Menendez (1989) These wealthy brothers, who grew up wealthy in the Los Angeles suburb of Calabasas, shot and killed their parents in order to inherit their money. The trial received national attention. Sarah Johnson (2003) The 16-year-old Idaho highschooler killed her parents with a high-powered rifle because they disapproved of her older boyfriend. Larry Swartz (1990) After spending most of his life in foster care, Larry Swartz was adopted by Robert and Kathryn Swartz. When the Swartz's adopted another son shortly after, conflicts in the family led Larry to murder his adopted mother. Stacy Lannert (1990) Stacey Lannert was in the third grade when her father Tom Lannert first began sexually abusing her. Adults near to Stacey, including her mother, suspected that Stacey was being abused, but failed to offer help. When Tom turned his attention to her younger sister Christy, Stacey felt there was only one solution left and killed her father.