
Cases of extended bouts of sequential killings over periods of weeks or months with no apparent "cooling off period" or "return to normality" have caused some experts to suggest a hybrid category of "spree-serial killer". The category has, however, been found to be of no real value to law enforcement, because of definitional problems relating to the concept of a "cooling-off period".
MISSION ORIENTED SERIAL KILLER EXAMPLES SERIAL
The lack of a cooling-off period (a significant break between the murders) marks the difference between a spree killer and a serial killer. Independent of the number of murders, they need to have been committed at different times, and are usually committed in different places. When defining serial killers, researchers generally use "three or more murders" as the baseline, considering it sufficient to provide a pattern without being overly restrictive. By the end of the 1990s, the use of the term had increased to 2,514 instances in the paper. Subsequently, throughout the 1980s, the term was used again in the pages of The New York Times, one of the major national news publications of the United States, on 233 occasions. Vronsky states that the term serial killing first entered into broader American popular usage when published in The New York Times in the spring of 1981, to describe Atlanta serial killer Wayne Williams. There is the mass murderer, or what he calls the "serial" killer, who may be actuated by greed, such as insurance, or retention or growth of power, like the Medicis of Renaissance Italy, or Landru, the " bluebeard" of the World War I period, who murdered numerous wives after taking their money. The Washington DC newspaper Evening Star, in a 1967 review of the book: In his book, Serial Killers: The Method and Madness of Monsters (2004), criminal justice historian Peter Vronsky notes that while Ressler might have coined the English term "serial homicide" within the law in 1974, the terms serial murder and serial murderer appear in John Brophy's book The Meaning of Murder (1966). The German term and concept were coined by criminologist Ernst Gennat, who described Peter Kürten as a Serienmörder ('serial-murderer') in his article " Die Düsseldorfer Sexualverbrechen" (1930). Author Ann Rule postulates in her 2004 book Kiss Me, Kill Me, that the English-language credit for coining the term goes to LAPD detective Pierce Brooks, who created the Violent Criminal Apprehension Program (ViCAP) system in 1985. The English term and concept of serial killer are commonly attributed to former FBI Special agent Robert Ressler, who used the term serial homicide in 1974 in a lecture at Police Staff Academy in Bramshill, Hampshire, England, United Kingdom.

