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Law and Crime

Origin of the Term “Serial Killer”

Serial killers have operated for centuries but the terminology is new.

Over the centuries, there have been hundreds of documented cases of serial murder around the world, but the term “serial killer” is relatively new. Up until the 1970s in the U.S., serial killers were generally called mass murderers by both the criminal justice system and the media.

Today, however, we draw a clear distinction between serial murder and mass murder. Unlike serial homicide, which is manifested in a number of separate events, mass murder is a one-time event that involves the killing of multiple people at one location. In a mass murder, the victims may be either randomly selected, or targeted for a specific reason, such as retaliation or revenge by the killer.

A mass murder normally occurs when the perpetrator, who is often deeply troubled, suffers a psychotic break from reality and strikes out at his/her perceived tormentors in a blitz-like attack. Unlike serial killers, mass murderers are frequently, but not always, killed at the scene of the crime. Sometimes, they are shot by law enforcement officers called to the crime scene, while other times mass murderers will take their own lives in a final act of suicide.

The movie theater massacre perpetrated by James Holmes in Aurora, Colorado, on July 20, 2012, on the opening night of The Dark Knight is a classic example of mass murder, as I explain in a separate article.

In contrast to mass murder, serial killing involves multiple incidents of homicide—committed in separate events and crime scenes—where the perpetrator experiences an emotional cooling-off period between murders. During the emotional cooling-off period (which can last weeks, months, or even years) the killer returns to his/her seemingly normal life. Unlike mass murderers, serial killers are not fatalistic and have no desire to be caught. They love killing far too much.

The late John Wayne Gacy, the “Killer Clown,” is a classic example of a highly prolific serial killer, as I explain in my article.

So, exactly where and when did the term “serial killer” originate? As explained by Peter Vronsky in his 2004 book Serial Killers: The Method and Madness of Monsters, the term “serial killer” was probably coined by the late FBI agent and profiler Robert Ressler. According to the story, Ressler was lecturing at the British police academy at Bramshill, England, in 1974, where he heard the description of some crimes as occurring in series, including rapes, arsons, burglaries, robberies, and murders.

Ressler said that the description reminded him of the movie industry term “serial adventures,” which referred to short episodic films, featuring the likes of Batman and The Lone Ranger, shown in theaters on Saturday afternoons during the 1930s and 1940s. Each week, youthful matinee audiences were lured back for the next installment in the series by an inconclusive ending known as a “cliffhanger” that left them wanting more (1).

The FBI agent recalled from his youth that no episode had a satisfactory conclusion and the ending of each one increased rather than decreased the tension in the viewer. Similarly, Ressler believed that the conclusion of every murder increases the tension and desire of a serial killer to commit a more perfect murder in the future—one closer to his/her ideal fantasy. Rather than being satisfied when they murder, serial killers are instead agitated toward repeating their killings in an unending “serial” cycle (2).


(1) Vronsky, P. 2004. Serial Killers: The Method and Madness of Monsters. New York: Berkley Books

(2) Ibid.

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