In an interview later in his life, Short told researcher George H. Morrison that he moved to the Black Hills in 1876 and to Ogallala, Nebraska the next year. Accounts written in Short's later years stated that he was an outlaw during his time in Nebraska. It was around this time that Short was said to have traded whiskey with Indians around Camp Robinson, Nebraska. According to his nephew Wayne Short, Luke was arrested by the army. They put him to a train destined for Omaha, but Luke managed to escape the army escort and went to the makeshift mining and cowtown of Denver, Colorado, taking up gambling as a profession. He is said to have killed two men on separate occasions due to altercations during their card games.