By 1851, San Francisco, California, had become a quite lawless and corrupt place, due to the massive influx of about thirty thousand immigrants caused by the California Gold Rush which occurred over a period of only two years. This left the city with a population of 31,000 people, 700 gambling houses, dirt roads, one law enforcement officer, and an average of six murders a week. Usually if someone was actually arrested for a crime, made it to trial, and was convicted, they could be free the same day by bribing the officials.

On February 19, 1851, Charles J. Jansen was robbed in his store by two men, who were quickly suspected to be Australian, which led to the arrest of Robert Windered and Thomas Berdue the next day. A crowd of 6,000 outside the hall of justice broke into the jail and almost hanged both of them in front of the court house (much to the distress of then Mayor John Geary), but was subdued by William Coleman who set up a mock trial and acted as prosecutor. Unfortunately, Coleman was easily defeated by the defense attorney Hall McAllister, even in his own mock trial, as Jansen could not identify the suspects. Thomas Berdue was handed over to the authorities, who held him on suspicion that he was James Stuart, wanted for crimes committed on the east coast.

On May 4 a fire destroyed nearly 25 blocks of the business district, and the Australians were immediately suspected.

This led the good citizens of San Francisco to turn to Sam Brannan, a town elder, who suggested William Coleman form a sort of militia to deal with the problem of crime in the city. He did, and thus began the first incarnation of the Vigilance Committee, which issued the following statement of purpose:

We are determined that no thief, burglar, incendiary, or assassin shall escape punishment either by the quibbles of the law, the insecurity of prisons, or the carelessness or corruption of the police, or the laxity of those who pretend to administer justice.

On June 10, they would figure out what that statement meant. John Jenkins was caught rowing away from Long Wharf with a stolen safe aboard his dingy. He was then turned over to the committee, was tried, found guilty, and hung at 1:30am the next day, to the delight of the good citizens, who celebrated underneath his dangling body all day until someone took it down late in the evening.

The Committee then proceeded to sweep through Sidneytown (a district of mainly Austrailian immigrants) and found a man who called himself William Stephens, and looked a lot like Thomas Berdue (who had been sent to the East Coast for trial for crimes committed by James Stuart.) William Stephens admitted (under questionable interrogation methods) to being James Stuart, and was then hung on July 11 at the end of the Market St. Wharf much to the delight of the crowds of good citizens.

In the next month, the Committee arrested, tried, and was holding Robert McKenzie and Samuel Wittaker awaiting execution. The Mayor, Charles Brenham, then ordered Sheriff John Hayes and his men to attempt to rescue the two criminals, which they did, and were then placed in the county jail. Four days later, a large force of Committee members broke into the jail, took McKenzie and Wittaker across town, and hung from the second floor window of the Committee's headquarters on Bush St. (Fifteen thousand gathered to watch the execution.)

September 16, 1851, the Committee suspended its operations after one hundred days, running 14 people out of town, placing 14 on ships destined for distant ports, hanging 4, and publicly flogging one. Thus ended the first incarnation of the Committee of Vigilance of San Francisco.

The Second Committee of Vigilance was formed in 1856 due to the murder of James King of William, a Maryland native who ran a San Francisco paper (The Bulletin) condemning the authorities, courts, and politicians of being corrupt (which they were). He had published an article accusing James P. Casey, a newly elected city supervisor, of stuffing ballot boxes (which he had, quite effectively.) Casey then shot William in a fit of rage, and walked away.

William Coleman immediately called a public meeting, and established the Second Committee, which had 2,500 members within two days, and ultimately reached 6,000 (compared to the previous which only reached 710). Aside from the increase in membership, the Second Committee was very heavily armed, including 4,000 infantrymen, four 100 man companies of artillery with thirty cannons, as well as two cavalry units, and a "brute squad".

The City's government at the time was controlled almost exclusively by the Law and Order Party, which didn't have any interest in either law or order, but only with making themselves richer through corruption. In order to pacify the people, the city officials were holding both James P. Casey and Charles Cora (a professional gambler who had been acquitted for the murder of a popular town elder) at the county jail. The Vigilantes, 2,500 strong, massed in front of the jail, cannons aimed, and demanded the release of the two prisoners, which the mayor agreed to without too much incident.

May 19, 1856, the trial began at Fort Gunnybags, the Committee's new headquarters. As the outcome of the trial had been decided before it began, both Casey and Cora were hung from the Committee's second story windows three days later.

Because of these events, Mayor James Van Ness secretly met with Governor J. Neely Johnson, to discuss the situation. In the mean time, though, the Committee put 25 people on ships, ran 15 out of town, and caused about 800 to leave without being told. They then decided to disband, but found it difficult to do, as Governor Johnson had declared San Francisco in a state of insurrection on June 3, and had President Pierce authorize a shipment of weapons for the State Militia to re-take the city. Unfortunately for the Governor, the shipment was intercepted by the Committee on June 19, and the Militia would never enter San Francisco.

In late June, a Committee member named Sterling Hopkins was stabbed in the neck by a Law and Order man named David S. Terry, who was a judge on the State Supreme Court. When the Committee captured Terry, many recognized that things were getting out of hand. A good number of people started to worry that the President would send the Army to re-take San Francisco after a State Supreme Court Justice was essentially kidnaped by the local uprising. Luckily, that never happened, as Hopkins survived (thanks to the help of the Vigilante surgeon R. Beverly Cole. Terry agreed to leave town, and the Second Committee of Vigilance of the City of San Francisco disbanded on August 18, 1856 after a military style parade down Market Street.

No Commitees of Vigilance have been formed since, but some have suggested it recently to rid the city of John Ashcroft's DEA, who have a nasty habbit of raiding medical marijuana clubs, and taking medicine from cancer patients.