Mutual combat, a term commonly used in United States courts, occurs when two individuals intentionally and consensually engage in a fair fight,^[1][2] while not hurting bystanders or damaging property. There have been numerous cases where this concept was successfully used in defense of the accused.^[3] In some cases, mutual combat may result in killings.^[4]

In 2012, MMA fighter Ben Fodor hit the headlines for engaging in mutual combat.^[5] A video of the fight went viral.^[6] The Seattle Police Department later defended their officers for not intervening.^[3] The Seattle Municipal Code 12A.06.025 states that "It is unlawful for any person to intentionally fight with another person in a public place and thereby create a substantial risk of: 1. Injury to a person who is not actively participating in the fight; or 2. Damage to the property of a person who is not actively participating in the fight."^[7] Thus since the fight did not injure a third party or damage property nor have a substantial risk to do so, it was allowed by this law.

Also in 2012, Gabriel Aubry and Olivier Martinez engaged in mutual combat and were not charged.^[8] In 2014, after Zac Efron had engaged in a fight in Skid Row, law enforcement officials did not make any arrests because they viewed it as mutual combat.^[9]

Mutual combat has been used to deny damage claims,^[10] as a legal defense,^[11] and to drop charges against fighting students.^[12]

Oregon law specifically bans mutual combat, according to subsection three of ORS 161.215: "a person is not justified in using physical force upon another person if: the physical force involved is the product of a combat by agreement not specifically authorized by law."

• Duel

• Street fighting