Zoosadism is pleasure derived from cruelty to animals. Zoosadism is part of the Macdonald triad, a set of three behaviors that are a precursor to sociopathic behavior. The term was coined by Ernest Borneman.
In 1971, American researchers profiled the typical animal harmer as being a nine-and-a-half-year-old boy, with an I.Q. of 91 and a history of gross parental abuse. Studies have shown that individuals who enjoy or are willing to inflict harm on animals are more likely to do so to humans. One of the known warning signs of certain psychopathologies, including antisocial personality disorder, is a history of torturing pets and small animals. According to The New York Times:
|“||The FBI has found that a history of cruelty to animals is one of the traits that regularly appear in its computer records of serial rapists and murderers, and the standard diagnostic and treatment manual for psychiatric and emotional disorders lists cruelty to animals as a diagnostic criterion for conduct disorders.||”|
Helen Gavin observed in Criminological and Forensic Psychology (2013):
|“||This is not a universal trait, though. Dennis Nilsen had difficulty initiating social contact with people, but loved his faithful companion, Bleep, a mongrel bitch. After his arrest, he was very concerned for her welfare, as she was taken to the police station too.||”|
Alan R. Felthous reported in his paper "Aggression Against Cats, Dogs, and People" (1980):
|“||A survey of psychiatric patients who had repeatedly tortured dogs and cats found all of them had high levels of aggression toward people as well, including one patient who had murdered a boy.||”|
This is a commonly reproduced finding, and for this reason, violence toward animals is considered a warning sign of potential violence towards humans.
In the United States, since 2010, it has been a federal offense to create or distribute "obscene" depictions of "living non-human mammals, birds, reptiles, or amphibians ... subjected to serious bodily injury". This statute replaced an overly broad 1999 statute which was found unconstitutional in United States v. Stevens.
Critics of the concept of a general neurological basis for cruelty to animals, let alone generalization to humans, cite the fact that animals can be cruel to some animals yet caring to other animals, combined with Pavlov's studies using metronomes at different rates to test conditioned learning showing that humans can discriminate in fine ways that animals cannot, and conclude that there is no such general basis. The exact way these critics explain studies that seems to show links varies, but most of them state that psychiatric and criminological studies are subject to institutional bias and self-fulfilling prophecies.
Zoosadism towards insects is also exhibited by some. The classic example of this subvariety of "schoolyard viciousness" is the child who pulls off a fly's wings. The Roman historian Suetonius, in his The Twelve Caesars, claimed that the Emperor Domitian amused himself by catching flies and impaling them with needles.
- Richard Chase
- Croydon serial cat killer, individual or individuals active in London, UK since c.2014
- John Duffy and David Mulcahy
- Jim Jones
- Ed Kemper
- Jun Matsubara
- Dennis Rader
- J. M. MacDonald (1963). "The Threat to Kill". American Journal of Psychiatry 120 (2): 125–130.
- Goleman, Daniel (7 August 1991). "Child's Love of Cruelty May Hint at the Future Killer". New York Times.
- Helen Gavin (2013). Criminological and Forensic Psychology. p. 120.
- Felthous, Alan R. (1980). "Aggression Against Cats, Dogs, and People". Child Psychiatry and Human Development (10): 169–177. doi:10.1007/bf01433629.
- Robson, Ruthann (2010-12-14) Animal Porn - Criminalized by Federal Law Again, Constitutional Law Prof Blog
- US Code TITLE 18 > PART I > CHAPTER 3 > § 48
- Catania, A.C. (1994). "Query: Did Pavlov's research ring a bell?". Psycoloquy Newsletter, June 7.
- Mad in America: Bad Science, Bad Medicine, and the Enduring Mistreatment of the Mentally Ill, 2002 RobertWhitaker
- The Unpredictable Species: What Makes Humans Unique by Lieberman, P 2013
- Tranquillus, C. Suetonius. "The Life of Domitian". The Twelve Caesars. p. 345.
- CrimeLibrary.com/Serial Killers/Truly Weird & Shocking/Richard Trenton Chase: The Vampire of Sacramento Archived October 11, 2007, at the Wayback Machine.
- Cowan, Rosie (11 August 2005). "Childhood cruelty to animals may signal violence in future". The Guardian (London). Retrieved 20 April 2010.