Scarborough was born in
Natchitoches Parish, Louisiana. His family moved to
Texas, where for a while he worked as a cowboy. In 1885, he was appointed sheriff for
Jones County. He would later work as a Deputy US Marshal in and around
El Paso, Texas. On June 21, 1895, while working alongside El Paso police chief Jeff Milton, Scarborough shot and killed Martin M'Rose, a Texas rustler. M'Rose is buried near
John Wesley Hardin, and Texas Ranger
Ernest St. Leon. Jeff Milton was Chief of Police in El Paso at that time, and Scarborough was a US Marshal. M'Rose had been captured, and was killed while being brought back from
Mexico by the two lawmen on an outstanding warrant. Outlaw, gunman and paramour of Mrs. M'Rose, John Wesley Hardin, claimed that he had paid Scarborough and Milton to kill Martin M'Rose. Milton and Scarborough were arrested, but Hardin later withdrew his comments and the men were released. Scarborough became well known for his unusual tactics when tracking a wanted outlaw. Often, he would drop himself down to the level of those he was pursuing. This tactic was extremely effective, and made him a hated and feared man among the outlaw element. There are many accusations that he was actively and ambitiously involved in outlaw gangs which he betrayed, but no one ever conclusively proved he was involved in unlawful actions. In July, 1898, Scarborough and Milton tracked, shot and captured outlaw
"Bronco Bill" Walters, killing another member of Walters' gang, and scattering the rest from their hideout near
Solomonville, Arizona. In late 1899 and into 1900, Scarborough pursued the
Burt Alvord gang. The beginning of the gang's end came during
a February 15, 1900, gunfight between five of the gang members and Jeff Milton in
Fairbank, Arizona, during which gang member
"Three Fingered Jack" Dunlop was killed, and both gang member Bravo Juan Yaos as well as Milton were wounded. ==Killing of John Selman==