A member of the American Society of Composers, Authors and Publishers (ASCAP) since 1942, Leopold was a veteran novelty songwriter ("Oh! How She Can Dance," 1919) who, as a piano accompanist to his wife, singer Emma Carus, toured vaudeville for many years. In the 1950s, the songwriter changed professions to work as a collection investigator for loan and credit companies. On December 28, 1956, the 66 year old was paying for groceries in a Hollywood market at 1921 N. Cahuenga
Avenue when a gunman burst into the store and demanded money from the counter attendant. The robber scooped $50.00 out of the register and was fleeing the scene when Leopold tossed a can of enchilada sauce at the gunman striking him in the shoulder. The man whirled, fired a single shot from a .38-caliber pistol, and ran to the parking lot where an accomplice waited in a light green sedan. Leopold, struck in the left temple, died a few minutes after being ambulanced to Hollywood Receiving Hospital. Shooter Charles F. Neely, 26, and wheelman Norman Golland, 30, were arrested the next day. Both pleaded guilty to the murder and were sentenced to terms of life imprisonment.