Justin Bieber won't face any criminal charges for punching a man -- who was allegedly choking a woman -- because the guy's not pressing charges, and cops can't confirm Bieber threw the punch.
Law enforcement sources tell TMZ ... cops responded Saturday to an altercation involving Bieber at a Coachella party. Cops say the man told them Bieber was involved, but they couldn't find any other witnesses who said Bieber got into it with the guy.
Further, the man does not want to press charges -- so, cops consider the matter closed. We're told officers were only responding for the Bieber incident. No one reported the choking, so the guy Bieber punched was also not arrested.
TMZ broke the story ... Bieber punched the guy after he allegedly grabbed the woman by the throat and would not release his grip. We're told when Bieber intervened the guy told him to "Go f*** yourself."