When can the conduct of one player toward another player be considered criminal? That's the question as Montreal police conduct their investigation into Tuesday's controversial check by Boston Bruins defenseman Zdeno Chara that sent the head of Montreal Canadiens forward Max Pacioretty into the glass partition between the benches. (The hit left Pacioretty with a severe concussion and cracked vertebra, although from this observer's perspective, it certainly did not seem criminal.)
While each state and country has its own criminal statutes, in order for conduct to be criminal, the state would usually be required to show two things: "actus reus" and "mens rea." To show actus reus, the Montreal police, who are acting on a request by Quebec's director of criminal and penal prosecutions, Louis Dionne, would need to establish that Chara's hit was a criminal act. With countless players being checked into the glass during a hockey game, it seems impossible that you could call Chara's hit criminal, regardless of the serious injury suffered by Pacioretty. (It must be the act that is criminal - you cannot impose criminal laws because of the seriousness of the injury.) This may be even more difficult to show after the NHL, upon reviewing the play, failed to suspend or fine Chara.
Mens rea represents an even tougher hurdle for the Montreal police - it means that the act was accompanied by a guilty mind. In other words, Chara must have known at the time of the hit that he was committing a criminal act. Once again, without direct evidence showing that Chara knew that the glass partition was there and that he intentionally sent Pacioretty crashing into it with conscious disregard of known serious risks, it would be almost impossible to establish that Chara believed that he was committing a criminal act when he checked Pacioretty.
If you look at both elements, it is clear that it will be difficult if not impossible to establish that Chara committed a crime.