Alvord began his career in law enforcement in 1886 as a deputy under Sheriff John Slaughter in Cochise County, Arizona, but turned to train robbery by the beginning of the 20th century.

[1] His father, a native of New York, worked as a prospector and mechanic for mining companies, but eventually came to hold public offices such as constable and justice of the peace in several of the places that the family lived.

Alvord served primarily as the muscle behind Slaughter's operations; he made several decisions which revealed his lack of experience and finesse in law enforcement.

[9] He did assist Slaughter in capturing or killing several rustlers and other outlaws between 1886 and 1889, but his reputation suffered when his alcoholism became increasingly apparent.

He formed a gang with outlaws Billy Stiles, Bill Downing, and "Three Fingered Jack" Dunlop, men he had once pursued during his career as a law officer.

On February 15, 1900, Dunlop was killed by lawman Jeff Milton during a bungled train robbery in Fairbank, Arizona, and gang recruit Bravo Juan Yoas was wounded.

Billy Stiles rode to Tombstone and wounded the deputy on duty, allowing Alvord and 24 other prisoners to escape.

In 1902, Alvord assisted Arizona Rangers Captain Burton C. Mossman in capturing the notorious Mexican bandit Augustine Chacon, in exchange for a share of the reward money and a reduced sentence.

In 1955, Alvord and Stiles were portrayed by Chris Drake and Paul Sorensen in an episode of the syndicated television series Stories of the Century, starring Jim Davis.