If you are a football fan you know that the NFL referees have been locked out and the league is using substitutes and that there is a huge controversy over the quality of the work they are doing. Also, there is a lot of talk about the fact that some players are playing much more violently because they think they can get away with it. I did not watch much football yesterday, so I missed this bit of news when it happened but just heard of a hit on the Texans' quarterback by a Denver Broncos' defender which resulted in a serious injury to the QB. According to the story, he will lose a little part of his left ear.
The refs did impose a penalty for the play, but the discussion now is whether the conduct was so far outside the lines that the injured player should have a claim for the injury. Torts students who used the Prosser textbook may remember Hackbart v. The Cincinnati Bengals in which the court discusses the concept of consent to intentional torts in the context of organized sports. According to the generally accepted view discussed in that case, players who voluntarily engage in organized sports agree to the inherent risks of the sport which includes conduct that violates the rules.
At some point, though, it could be argued that the conduct is so far outside the rules and customs of the game that it should be actionable. If the player had purposely taken the QB's helmet off and then bit into his ear, a la Mike Tyson, I'd say you can argue for possible liability. Likewise, maybe if the hit had happened some time after the play had been blown dead and the QB had let down his guard; but that would depend on how much time had passed.
But the case is much closer when the play is fast, before the whistle blows, even though the player goes for a hit to the head, etc. Yes, the hit is illegal according to the rules but it is still a known risk of the game. The video I saw of the play in question here, in my opinion, does not show a blatantly late hit. It is not the lateness of the hit that was the problem. It was the fact that it was clearly -in my opinion at least- to the head of the QB.
Clearly, the fact the play is against the rules is not going to be enough to justify allowing possible liability. What would be enough, is not all that clear, though. Professor Jonathan Turley has a good discussion of the question in his blog which you can read here.