The John Kinney Gang, also known as the Rio Grande Posse, was an outlaw gang of the old West, which operated during the mid-1870s into the mid-1880s.
The gang was organized by outlaw John Kinney, in Doña Ana County, New Mexico. From its beginning, the gang primarily committed acts of robbery and cattle rustling.
However, they became best known when they were enlisted by the "Murphy-Dolan Faction" during the Lincoln County War, to counter Billy the Kid and his "Regulators". Former gang member Jesse Evans and his gang also were enlisted by "Murphy-Dolan". Lincoln County Sheriff George Peppin deputized the gang members to make them "official" during this time.
After the Lincoln County War ended, they resumed their previous criminal activities, with some members remaining with the Kinney Gang, while others joined the Jesse Evans Gang, or John Selman's gang.
The Kinney Gang ended when John Kinney was arrested, in 1883, for rustling. He was released from prison in 1886, but by that time all former gang members had either disappeared, were in prison or dead. John Kinney did not return to his former outlaw life, served in the US Army during the Spanish American War, and lived until 1919.