From The Art and Popular Culture Encyclopedia
Copycat crimes are criminal acts that are modeled on previous crimes that have been reported in the media.
The copycat effect refers to the tendency of sensational publicity about violent murders or suicides to result in more of the same through imitation. It is also the name of a book on the subject by Loren Coleman.
Research on etiology of copycat crimes
It has been shown that most of the persons who do mimic crimes seen in the media (especially news and crime movies) have in most cases prior criminal records, prior severe mental health problems or histories of violence suggesting that the effect of the media is indirect (more affecting criminal behaviour) rather than direct (directly affecting the number of criminals). It has also been seen that there is a certain small population of people who are at more risk for harmful media influences than the general audience.