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The term copycat effect was coined after intense coverage of the Jack the Ripper murders spawned similar killings.
Murders usually clustered under the umbrella of stranger killings -- spree, serial and mass murders -- are considered particularly reprehensible. For one thing, they lack a clear motive; with most murders, the rationale is a desire for retribution or financial gain. This generally isn't the case with so-called stranger murders. A violent act committed against someone the perpetrator doesn't know must be the act of an insane person. Yet, many stranger killers don't meet the criteria for insanity. What's more, the field of psychology has struggled to create a psychological model that explains all of these acts.
The rationale for another type of murder is much clearer. Copycat killings -- murders committed in a way already established by a previous murder committed by another person -- are generally believed to be generated in part by the media.
Since 1912, when the term "copycat effect" came about in response to the intense coverage of the Jack the Ripper murders spawned a multitude of similar crimes, criminologists has been aware of the potential for media exposure to lead to copycats. As the media has grown, other forms of entertainment -- especially movies -- have come under fire for allegedly leading to copycat killers who've based their crimes on the actions and characters in certain films.
What follows are five crimes and criminals that inspired others to follow in their brutal footsteps.
