The Macdonald triad is a set of three behavioral characteristics which are associated with sociopathic behavior. These behavioral characteristics are found in the childhood histories of individuals with sociopathic behavior:

1. Enuresis (bedwetting)
2. Firesetting
3. Torturing small animals

The Macdonald triad is also known as the triad of sociopathy. It was first identified by a forensic psychiatrist, John Marshall Macdonald (November 7, 1920 - December 16, 2007), in a 1963 paper in the American Journal of Psychiatry titled "The Threat to Kill".

The Macdonalt triad is considered predictive of future criminal behavior.