Serial killing is the murder of two or more victims by the same person at different times. In addition, according to criminologists (experts who study crime and criminals), to be classified as a serial killing the murders must occur as separate events over a period of time. Serial killing is different from mass murder. Mass murder is the killing of multiple people at the same time in the same location. Serial killing is also different from spree killing. Spree killing is the murder of multiple people in different locations within a short period of time.
There are several different types of serial killers. The most common type is the sexually motivated serial murderer. This individual kills because the murder itself gives the offender sexual pleasure. Criminologists generally classify Americans Ted Bundy, Jeffrey Dahmer, Albert DeSalvo, and John Wayne Gacy as sexually motivated serial killers.
Another type of serial killer is the “angel of death,” who kills in such health care settings as hospitals and nursing homes. The American physician Michael Swango is considered an angel-of-death type of serial killer. Contract killers—such as American Mafia member Richard “the Iceman” Kuklinski—usually work within organized crime groups and kill multiple people for profit. There are also individuals who, over the course of their criminal careers, perform serial killings in connection with various types of antisocial behavior. Antisocial behavior includes actions that show a regular disregard for, and violate the rights of, others.
There are many myths about serial killers, often based on Hollywood movies. The plot lines and characters of such fictional serial killers as Dr. Hannibal Lecter in the film The Silence of the Lambs (1991) are created to heighten the audience’s interest. These characterizations, however, are not realistic. Not all serial killers are highly intelligent white males who travel extensively while committing murders. Although most serial killers are male, all ethnic and racial groups are represented. Most serial killers are only of average intelligence. Such killers are not usually loners. In fact, many are married and live with their family. The vast majority of serial killers commit their crimes in the area where they live or work. It is rare for serial killers to travel any distance from the places with which they are familiar.
Serial killers also vary in how they carry out their crimes. Some commit crimes in a carefully planned fashion. Such serial killers are aware of how forensic evidence—that is, evidence used for legal purposes—is gathered. This knowledge makes it more difficult for law enforcement officers to catch the murderers. Other serial killers act impulsively with little planning. These killers leave evidence behind that makes it much easier for authorities to make an arrest after one or two murders.
Serial killing is not a modern phenomenon, nor is it more prevalent in any particular country. Historians and criminologists have discovered instances of serial killing over the last 2,000 years in a number of countries and cultures. Over the last 150 years, many individuals who have committed serial killings have been described and carefully examined. As early as 1886, the German psychiatrist Richard von Krafft-Ebing provided one of the first scientific accounts of serial sexual killing in his classic book Psychopathia Sexualis. Nevertheless, serial killing was always, and still is, quite rare. Criminologists estimate that fewer than 1 percent of all homicides committed are serial killings.
Since the early 1980’s, serial murder has become the subject of formal scientific study by criminologists. Experts hope that such study will enable law enforcement authorities to catch serial killers more quickly and to prevent future crimes.
