Zoosadism

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:

Helen Gavin observed in Criminological and Forensic Psychology (2013):

Alan R. Felthous reported in his paper "Aggression Against Cats, Dogs, and People" (1980):

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.

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