Serial killer

A serial killer, also known as a serial murderer, is someone who kills three or more people in separate incidents that occur over more than a month. The Federal Bureau of Investigation identifies possible motives such as anger, the pursuit of thrills, a desire for attention, or financial gain. Victims often share common traits, like age, gender, race, or general appearance. While serial killers frequently exhibit various personality disorders, they are usually not considered legally insane. The core drive behind these murders is typically some form of psychological gratification, which is often, but not always, sexual.

The term "serial killer" in English is widely credited to former FBI agent Robert Ressler, who used "serial homicide" in a 1974 lecture in England. However, author Ann Rule argues that LAPD detective Pierce Brooks coined the term in English when creating the ViCAP system in 1985. The German equivalent, *Serienmörder*, was used earlier by criminologist Ernst Gennat in 1930 to describe Peter Kürten. Criminal justice historian Peter Vronsky notes that the phrases "serial murder" and "serial murderer" appeared in John Brophy's 1966 book *The Meaning of Murder*, and a 1967 review in the *Evening Star* newspaper referenced Brophy's use of "serial" killer. The term entered broader American usage in 1981 when *The New York Times* used it to describe Atlanta serial killer Wayne Williams; the paper used the term 233 times in the 1980s and 2,514 times by the end of the 1990s.

Researchers generally set the baseline for a serial killer at three or more murders, as this establishes a pattern without being too restrictive. The murders must occur at different times and usually in different locations. The key distinction between a serial killer and a spree killer is the presence of a "cooling-off period" between murders, though this concept has been criticized as unhelpful for law enforcement. Some experts propose a hybrid "spree-serial killer" category for cases where extended bouts of killing occur over weeks or months without an apparent return to normalcy. Fuller and Hickey, in *Controversial Issues in Criminology*, emphasize that the time between acts is the primary factor in distinguishing serial, mass, and spree murderers, with spree killers acting over days or weeks. Andrew Cunanan is cited as a spree killer, Charles Whitman as a mass murderer, and Jeffrey Dahmer as a serial killer. In 2005, the FBI hosted a symposium in San Antonio, Texas, where 135 experts agreed on a standard definition of serial murder as "the unlawful killing of two or more victims by the same offender(s) in separate events." Researcher Enzo Yaksic supported lowering the threshold from three to two victims, noting that serial murderers from these groups share similar pathologies.

Historical criminologists believe serial killers have existed throughout history, with some suggesting that legends of werewolves and vampires were inspired by medieval cases. In Africa, there were periodic outbreaks of murder by "leopard men." In China, around 144 BC, Prince Liu Pengli, nephew of Emperor Jing, led expeditions with slaves and outlaws, murdering people for sport and seizing their belongings. It was not until the 29th year of his reign that a victim's son reported him; after it was discovered he had killed at least 100 people, the Emperor made him a commoner and banished him. In the 9th century (year 257 of the Islamic Calendar), a strangler in Baghdad was apprehended after murdering several women and burying them in his home. The majority of documented serial killers have been active in the United States.