Santiago Brito, county sheriff and city marshall in Brownsville, was probably born in the Rio Grande valley. He was married and had a family of five children. He was owner of El Demócrata, a Spanish-language newspaper in Brownsville, before he was elected Cameron county sheriff in 1884. Newspaper accounts of Brito's accomplishments as a lawman regularly appeared in regional newspapers during the 1880s. In 1890 Matthew L. Browne won the office of sheriff, and, on December 1, 1890, Brito applied for and received the post of Brownsville city marshall. Some time before, he had been made a special Texas Ranger by order of Governor Lawrence Sullivan Ross.
On January 19, 1891, the Rio Grande Railroad was robbed of some $75,000 as well as government mail. Brito succeeded in capturing José Mosqueda, the leader of the outlaws, and thus became part of the folklore of the Texas Mexican community. Brito's involvement in the investigation was initially the idea of Simón Celaya, the general manager of the railroad, who was financially responsible for the stolen goods. He was later sued by a Mexican company for the loss of 10,500 silver pesos and gold worth $9,110. The territorial authority brought Brito in conflict with Sheriff Browne, in whose jurisdiction the crime occurred. Browne and Brito both organized posses to hunt the outlaws and apparently argued about their power over the case. Brito solved the case in nine days. He and a posse made up of his former deputies searched the scene of the robbery and combed the surrounding area for the criminals. He found two witnesses, a boy whose uncle was involved in the crime and a vaquero who had found the tool used to derail the train. Uncovering the "home-made spike-puller" led Brito to the blacksmith who had forged it and ultimately to José Mosqueda and his accomplices. When Brito refused to hand his prisoners over to Browne, John M. Haynes, a United States marshall, had to intervene and place the prisoners in the only available jail, which was in Brownsville, thus landing them in Browne's custody. Much of the money was apparently never recovered. Mosqueda and one other conspirator were sentenced to life and ten-year sentences, respectively. Both reportedly died in jail. Browne was shot on a cattle drive less than a year after the train robbery, and Brito was shot and killed in August 1892.
"El Corrido de José Mosqueda" was composed in the 1890s to commemorate the event. A version of almost a half century later presents Brito as a coward fleeing from Mosqueda after a skirmish and Mosqueda as a hero. See also CORRIDOS.