Pride of the Bowery (1940)

Danny, managing boxer Muggs, books him into a Civilian Conservation Corps camp for training. Muggs' arrogant manner soon alienates him from the other boys who downright ostracize him with a camp-wide silent treatment after Muggs' public display of bad sportsmanship in a camp boxing match. One of the few boys still willing to talk to him is Willie, a cowardly and manipulative sort, who privately admits he stole $100 from the Captain's safe to send to his aunt and begs Muggs for help. In Muggs' world you aid a friend in trouble, so he enters a city boxing tournament to earn replacement money for Willie. Willie, however, allows Muggs to get caught trying to replace the money. Muggs stoically takes the rap for stealing, but Danny, a true and observant friend, knows something's up and clears Muggs by capturing and beating a confession out of Willie. The Captain leaves Muggs with the lesson that ratting out a friend is sometimes the right thing to do.