Fighting Back (1948)

Nick Sanders is honorably discharged from the army, with a full pardon for his pre-war crimes, and settles into a happy home life with his wife, June, and their son, Jimmy, and the family dog, "Snuffy." The latter likes to steal and hide things. When Nick brushes off his ex-partner in crime, Sam Lang, the smooth crook uses "Snuffy" to rob the Higby home of a valuable diamond. The dog bolts with the loot. The police suspect Nick of the crime.