Crime of passion

A crime of passion, or crime passionnel (from French), in popular usage, refers to a violent crime, especially homicide, in which the perpetrator commits the act against someone because of sudden strong impulse such as sudden rage rather than as a premeditated crime.

The defense in the crime of passion challenges the mens rea element by arguing that there was no malice aforethought and instead the crime was committed in the "heat of passion" and lowers the charge to manslaughter or second degree murder from first degree murder. Examples include an aggressive pub-goer who assaults another guest following an argument, or a wife who discovers her husband has engaged in adultery and attacks or kills him and/or his mistress.

In the United States, claims of "crimes of passion" have been traditionally associated with the defenses of temporary insanity or provocation. This defense was first used by U.S. Congressman Daniel Sickles of New York in 1859 after he had killed his wife's lover, Philip Barton Key. It was used as a defense in murder cases during the 1940s and 1950s. Historically, such defenses were used as complete defenses for various violent crimes, but gradually they became used primarily as a partial defense to a charge of murder; if the court accepts temporary insanity, a murder charge may be reduced to manslaughter.

In some countries, notably France, crime passionnel (or crime of passion) was a valid defense to murder charges. During the 19th century, some such cases resulted in a custodial sentence for the murderer of two years. After the Napoleonic code was updated in the 1970s, paternal authority over the members of the family was ended, thus reducing the occasions for which crime passionnel could be claimed. The Canadian Department of Justice has described crimes of passion as "abrupt, impulsive and unpremeditated acts of violence committed by persons who have come face to face with an incident unacceptable to them and who are rendered incapable of self-control for the duration of the act."

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