Ask any hockey fan about the NHL's Department of Player Safety and you'll probably be met with eye rolls, snorts of disgust, or flat out anger. As ineffective and inconsistent as discipline can be at the NHL level, it's shortcomings pale in comparison to the American Hockey League.
The in game refereeing does a terrible job of keeping players safe, and instead lets things get so out of control that people get hurt. When players do malicious or dangerous things that have no place in hockey and go unpunished in the game, it's supposed to be the league's job to hand out discipline to those players to teach them that their actions are not acceptable.