Under the law of England and Wales and other common law jurisdictions, it originally consisted of the intentional and wanton removal of a body part that would handicap a person's ability to defend themself in combat. Under the strict common law definition, initially this required damage to an eye or a limb, while cutting off an ear or a nose was deemed not sufficiently disabling. Later the meaning of the crime expanded to encompass any mutilation, disfigurement, or crippling act done using any instrument.
This article needs to be updated.(August 2011)
In England and Wales, it has fallen into disuse. In 1992 the Law Commission recommended that it be abolished, and in 1998 the Home Office proposed to abolish it, in the course of codifying the law relating to offences against the person.
The most significant change in common-law mayhem doctrine came in 1697, when the King's Bench decided Fetter v. Beale, 91 Eng. Rep. 1122. There, the plaintiff recovered in a battery action against a defendant. Shortly thereafter, "part of his skull by reason of the said battery came out of his head", and the plaintiff brought a subsequent action under mayhem. Though Fetter is also known as an early example of res judicata, it is most significant for expanding the ambit of mayhem to include "loss of the skull".
Modern statutes in the U.S. define mayhem as disabling or disfiguring, such as rendering useless a member of another person's arms or legs. Cal. Pen. Code Sec. 203 The injury must be permanent, not just a temporary loss. Some courts will hold even a minor battery as mayhem if the injury is not minor. Mayhem in the U.S. is a felony.
Both the noun "mayhem" and the verb "maim" come from Old French via Anglo-Norman. The word is first attested in various Romance languages in the 13th century, but its ultimate origin is unclear. For one hypothesis about its origin, see the Wiktionary entry for this word.
Mayhem can describe a person going on a rampage. Popular misunderstanding of the common journalese expression "rioting and mayhem" caused the common usual modern use of "mayhem" to mean "havoc and disorder", often with humorous overtones.