Crime Library: Criminal Minds and Methods

What Makes Serial Killers Tick?

The Triad

Animal Cruelty

These secret compulsions are seen as the seeds to greater mayhem. "Violent acts are reinforced, since the murderers either are able to express rage without experiencing negative consequences or are impervious to any prohibitions against these actions. Second, impulsive and erratic behavior discourages friendships," increasing isolation." "Furthermore, there is no challenge to the offenders' beliefs that they are entitled to act the way they do." (Ressler, et al, Sexual Homicide) "All learning, according to Ressler, has a "feedback system." Torturing animals and setting fires will eventually escalate to crimes against fellow human beings, if the pattern is not somehow broken.

Torturing animals is a disturbing red flag. Animals are often seen as "practice" for killing humans. Ed Kemper buried the family cat alive, dug it up, and cut off its head. Dahmer was notorious for his animal cruelty, cutting off dogs heads and placing them on a stick behind his house. Yet not all serial killers take their aggressions out on pets. Dennis Nilsen loved animals, particularly his dog Bleep, whom he couldn't bear to face after being arrested for fear that it would traumatize the dog. Rapist torturer and murderer of eight, Christopher Wilder, had made donations to Save The Whales and the Seal Rescue Fund.


Peter Kurten loved to watch houses burn, and Berkowitz, when he tired of torturing his mother's parakeet, became a prolific pyromaniac, keeping record of his 1,411 fires. "Oh, what ecstasy," said Joseph Kallinger to his biographer Flora Schreiber, "setting fires brings to my body! What power I feel at the thought of fire! ... Oh, what pleasure, what heavenly pleasure!" Pyromania is often a sexually stimulating activity for these killers. The dramatic destruction of property feeds the same perverse need to destroy another human. Because serial killers don't see other humans as more than objects, the leap between setting fires and killing people is easy to make.

Bed Wetting

Bed wetting is the most intimate of these "triad" symptoms, and is less likely to be willfully divulged. By some estimates, 60% of multiple murderers wet their beds past adolescence. Kenneth Bianchi apparently spent many a night marinating in urine-soaked sheets.


Formative years may play a role in the molding of a serial killer, but they cannot be the sole reason in every case. Many killers blame their families for their behavior, seeking sympathy. In true psychopathic fashion, serial killers are blaming someone else for their actions. If their bad childhood is the primary reason for their homicidal tendencies, then why don't their siblings also become serial killers? And if these conditions truly created them, serial killers would probably be unionized by now, there would be so many of them (a sad commentary on our continuing neglect of children.) We must look at other components to see what pushes a serial killer over the edge.

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