the MacDonald triad

The MacDonald triad refers to three behavioral traits historically linked to later violent or criminal behavior, particularly murder. These are bed-wetting past the age typical for toilet training, fire-setting, and cruelty to animals. The idea is that these behaviors might indicate underlying psychological issues or tendencies toward aggression. However, modern research has shown that the triad is not a reliable predictor of future violence, and many individuals displaying these behaviors do not become violent. It remains a concept discussed in forensic psychology but should be understood as one of many factors in assessing behavior, not a definitive warning sign.