The Classification and Rating Administration originally slapped the film with an R rating for the violent and bloody train attack that the film is focused on.
Clint Eastwood is a man who needs no introduction, so I imagine the appeals board was extra inclined to hear his case.
I’d also like to think that Clint Eastwood put on a cowboy hat and did his best Bill Munny at the appeal hearing.
So no doubt Clint Eastwood emphasized the larger story of these men’s lives and how a moment of violence should not subject the film to an R rating.