John Behan was born in Westport, Missouri, on 25th October, 1845. As a young man he travelled to California. He worked as a freighter at Fort Lowell, a miner at Cerro Colorado, and a bull whacker at Prescott.
In 1866 Behan became under sheriff to John Bourke of Yavapai County where he gained a reputation as a brave and honest lawman. He also served as sheriff in Yavapai County (1871-72). A member of the Democratic Party, Behan became a member of the state assembly in 1873.
In 1880 Behan became sheriff of Cochise County. Soon afterwards Virgil Earp became city marshal of Tombstone. In this role he recruited Wyatt Earp and Morgan Earp as "special deputy policemen". In 1880 the Earp family came into conflict with two families, the Clantons and the McLaurys. Ike Clanton, Phineas Clanton, Billy Clanton, Tom McLaury and Frank McLaury sold livestock to Tombstone. Virgil Earp brothers believed that some of these animals had been stolen from farmers in Mexico. Wyatt Earp was also convinced that the Clanton brothers had stolen one of his horses.
Wyatt Earp also came into conflict with Behan. At first this started as a quarrel over a woman, Josephine Sarah Marcus. She had lived with Behan before becoming Earp's third wife. Earp also wanted Behan's job and planned to run against him in the next election. The two men also clashed over the decision by Behan to arrest Doc Holliday on suspicion of killing a stage driver during an attempted hold-up outside of town. Holliday protested his innocence and he was eventually released. In September 1881, Virgil Earp retaliated by arresting one of Behan's deputies, Frank Stilwell, for holding up a stagecoach.
On 25th October, Ike Clanton and Tom McLaury arrived in Tombstone. Later that day Doc Holliday got into a fight with Ike Clanton in the Alhambra Saloon. Holliday wanted a gunfight with Clanton, but he declined the offer and walked off.
The following day Ike Clanton and Tom McLaury were arrested by Virgil Earp and charged with carrying firearms within the city limits. After they were disarmed and released, the two men joined Billy Clanton and Frank McLaury, who had just arrived in town. The men gathered at a place called the OK Corral in Fremont Street.
Virgil Earp now decided to disarm Billy Clanton and Frank McLaury recruited Wyatt Earp, Morgan Earp, James Earp and Doc Holliday to help him in this dangerous task. Behan was in town and when he heard what was happening he raced to Fremont Street and urged Billy Clanton and Frank McLaury to hand over their guns to him. They replied "Not unless you first disarm the Earps".
Behan now headed towards the advancing group of men. He pleaded for Virgil Earp not to get involved in a shoot-out but he was brushed aside as the four men carried on walking towards the OK Corral. Virgil Earp said: "I want your guns". Billy Clanton responded by firing at Wyatt Earp. He missed and Morgan Earp successfully fired two bullets at Billy Clanton and he fell back against a wall. Meanwhile Wyatt Earp fired at Frank McLaury. The bullet hit him in the stomach and he fell to the ground.
Ike Clanton and Tom McLaury were both unarmed and tried to run away. Clanton was successful but Doc Holliday shot McLaury in the back. Billy Clanton and Frank McLaury, although seriously wounded, continued to fire their guns and in the next couple of seconds Virgil Earp, Morgan Earp and Doc Holliday were all wounded. Wyatt Earp was unscathed and he managed to finish off Billy Clanton and Frank McLaury.
Behan arrested Virgil Earp, Wyatt Earp, Morgan Earp and Doc Holliday for murder of Billy Clanton, Tom McLaury and Frank McLaury. However, after a 30 day trial Judge Wells Spicer, who was related to the Earps, decided that the defendants had been justified in their actions.
In 1888 Behan became superintendent of the Territorial State Prison at Yuma. Later he was a U.S. agent at El Paso where he attempted to control smuggling in the area. Behan was also employed as a government special agent in China during the Boxer Rebellion.
John Behan died in Tucson on 7th June, 1912.