Outlaw Joe Walker rode with the famous "Wild Bunch" gang led by Butch Cassidy. The trouble seems to have started with his problems with the Whitmore family in Carbon County, Utah. The Whitmores were prominent bankers and ranchers in Utah and their father was Walker's uncle. The uncle had managed the Walker cattle after Joe's father had died and Joe was a little kid.
Whitmore combined the herd and moved to Arizona where he was killed by Indians, whereupon his widow and sons moved to Utah. When Walker's mother died, he went to Utah to settle up on the "cattle matter" but the Whitmores denied any relationship or claims to any cattle. As a result, Walker began to run with some outlaws at nearby "Robbers Roost" in Utah, and he often stole cattle from the Whitmores.
In 1897, Walker was with the "Wild Bunch" when they pulled off an $8000 robbery from the Castle Gate payroll. Walker stole some Whitmore cattle in 1898 and was chased by a 9-man posse. Walker and a cowboy named Johnny Herring bedded down for the night and the posse found them early the next morning. The posse mistakenly thought they had found Butch Cassidy and the Sundance Kid, (of "Wild Bunch" fame, who were known for shooting their way out of being arrested) so they all surrounded the two men, and pumped the two of them full of lead, while they were still in their bedrolls.