In response, the Mexican government eventually lowered tariffs and added forts along the border making cross-border rustling and smuggling less attractive.

Outlaws from all parts of the Western territories felt the pressures of encroaching civilization and the increased presence of lawmen and the courts, backed by growing populations of farmers and citizens desiring law and order.

The town had boomed in less than 18 months from about 100 miners living in tents and shacks to more than 7,000 people by December 1, 1879, when Virgil, Wyatt, and Morgan Earp arrived in Tombstone.

Marshal for eastern Pima County in Prescott and was directed to relocate to Tombstone to concentrate on suppressing the Cowboys' illegal activities.

When those didn't work out, Wyatt Earp started riding shotgun for Wells, Fargo & Co., guarding their silver bullion shipments.

[4] While cowhands were still respected in West Texas,[5] in Cochise County the outlaws' crimes and their notoriety grew such that during the 1880s it was an insult to call a legitimate cattleman a "cowboy."

The San Francisco Examiner wrote in an editorial, "Cowboys [are] the most reckless class of outlaws in that wild country ... infinitely worse than the ordinary robber.

[8] There were said to be strongholds in the San Simon Valley where the bandits concealed stolen cattle until they were rebranded and sent to market, and where no officer of the law dared to venture.

Virgil Earp thought that some of the Cowboys had met at Charleston, Arizona, and taken "an oath over blood drawn from the arm of Ringo, the leader, that they would kill us.

[14][15] Many of the ranchers and cowboys who lived in the countryside were resentful of the growing power of industrialists from northern states, who increasingly influenced local politics and law in the county.

When the Cowboys broke the law, the businessmen feared alienating their customers and hesitated to support lawmen when they confronted cattle thieves or stage robbers.

On March 15, 1881, three Cowboys tried to rob a Kinnear & Company stagecoach carrying US$26,000 in silver bullion (about $820,883 in today's dollars) near Drew's Station, just outside Contention City.

[6] Old Man Clanton was involved in the robbery, murder, and torture of a number of Mexican smugglers who were ambushed on their way to Tucson in the 1879 Skeleton Canyon Massacre.

[22] Law enforcement officers who came into conflict with the Cowboys included Fred White, who was killed by Curly Bill Brocius in what was ruled an accidental shooting.

Many of the very best law-abiding and peace-loving citizens have no confidence in the willingness of the civil officers to pursue and bring to justice that element of outlawry so largely disturbing the sense of security, and so often committing highway robbery and smaller thefts.

The opinion in Tombstone and elsewhere in that part of the Territory is quite prevalent that the civil officers are quite largely in league with the leaders of this disturbing and dangerous element.

It is hereby declared unlawful to carry in the hand or upon the person or otherwise any deadly weapon within the limits of said city of Tombstone, without first obtaining a permit in writing.

[26] In his ruling exonerating the lawmen of murder, Judge Spicer described Frank McLaury's insistence that he would not give up his weapons unless the marshal and his deputies also gave up their arms as a "proposition both monstrous and startling!

After Town Marshal Fred White was killed on October 30, 1880, Virgil was appointed to replace him, gaining the position permanently on June 2, 1881.

"[28]: 185 At about 11:30 pm on December 28, 1881, Virgil Earp was ambushed on the streets of Tombstone by hidden assailants shooting from the second story of an unfinished building as he walked from the Oriental Saloon to his room.

The Sacramento Daily Record-Union reported that "he was fired upon with double-barreled shotguns, loaded with buckshot, by three men concealed in an unfinished building diagonally across on Allen street.

[30] The Crystal Palace Saloon and the Eagle Brewery beyond Virgil were struck by nineteen buckshot; three passed through the window and one about a foot over the heads of some men standing by a faro-table.

The Sacramento Daily Record-Union wrote that "Long ago the cowboy gang threatened the lives of Mayor Clum, Judge Spicer, Marshall Williams, agent of Wells, Fargo & Co., Earp and Holliday, and this is an attempt to carry the threats into execution.

Marshal to replace Virgil; in turn, he deputized Sherman McMaster, "Turkey Creek" Jack Johnson, Origen Charles Smith and Daniel "Tip" Tipton.

[32] Pete Spence, Frederick Bode, Frank Stilwell, "Indian Charlie" Cruz, and one other individual were identified as suspects in Morgan's murder.

Newly named as Deputy US Marshal to replace Virgil, he assembled a posse including Warren Earp, Doc Holliday, and several cowboys.

He eventually was arrested for numerous crimes, including cattle rustling and robbery, and was convicted and sentenced to five years in prison at Santa Fe, New Mexico.

Tritle telegraphed President Chester A. Arthur and asked for an appropriation of $150,000 from Congress to pay for the costs of rooting out the unlawful elements.

[43]: 195 To combat the depredations of the outlaw cowboys, General William T. Sherman, following a tour of Arizona's eastern and southern counties, recommended suspension of the Posse Comitatus Act to allow the U.S. Army to aid in restoring order.

On the basis of the recommendations of Sherman and Tritle, and following consultation with members of the U.S. Senate, President Arthur issued a decree on May 3, 1882, threatening to use military force if the criminal element did not disperse.