The Kid from Arizona (1931)

Marshal Jack is sent, undercover, into the bad lands to clean up a gang of Indians who have been terrorizing the local ranchers. Horses belonging to a ranch owner are stolen and the horse which was supposed to be in an endurance race is maimed. Jack is blamed for both deeds. He acquits himself and wins the race for The Colonel, after disclosing that the supposed band of Indians are a pack of white smugglers led by the ranch foreman.