NHL: I wrote a head-shots rule fer ya; feel free to cut/paste
When I played, which was a long time ago, my shoulder pads were little pieces of plastic and cardboard. At least, they seemed like cardboard. There was a little cup of plastic on each shoulder, and some soft material in between. I took ten years off before my first beer league game, and I couldn't believe the change in equipment. It's armor now. I've been reading lately that people are looking into making softer shoulder and elbow pads. You know, so that they can't be used as weapons.
There has been a lot of talk lately about clean hits vs. legal hits -- can a hit be legal and still be dirty, etc. (my answer: no). A hit can cause injury and be clean and legal, but it can't be dirty and be legal. Intent to injure is against the rules, period. If dirty doesn't carry the implication of intent to injure, it doesn't mean anything. You can't be accidentally dirty.
The latest Matt Cooke head-shot on Marc Savard brought up the question of blind-side hits. There already is a rule against hitting from behind, which almost applies (because Savard never saw it coming) but doesn't, because he wasn't hit "in the back." (It sounds like the league is thinking about banning blind-side hits, effectively closing the loop-hole in the hitting from behind rule. That's excellent.)
Charging, meanwhile, actually covers this hit and a lot of head-shots, if you follow the literal meaning of the words in the rules (which you can't, because it's so badly written):
43.1 Charging - A minor or major penalty shall be imposed on a player or goalkeeper who skates or jumps into, or charges an opponent in any manner.
Charging shall mean the actions of a player or goalkeeper who, as a result of distance traveled, shall violently check an opponent in any manner. A "charge" may be the result of a check into the boards, into the goal frame or in open ice.
Okay, now the way this is written, it actually makes no sense. "A minor or major penalty shall [must] be imposed on a player or goalkeeper who skates [...] into [...] an opponent in any manner"?? That literally says, "every body check must be a penalty." As a result, everyone just ignores what the rule book says and reverts to our decades-old understanding of the rule: you can't take more than two strides in a straight line to check an opponent.
The actual rule even gets more vague in the second paragraph: "Charging shall mean the actions of a player or goalkeeper who, as a result of distance traveled, shall [sic] violently check an opponent in any manner." Virtually every check is "a result of distance traveled." (I actually think about 90% of the confusion regarding NHL rules would be cleared up by a good copyeditor; for example, the stupid "intent to blow" controversy, but I digress...) A ref could easily decide any blow to the head is covered by these craptastic Charging paragraphs. But it would be so much better simply to put head-shots in the rule book.
Matt Cooke had the opportunity to hit Marc Savard on the "side" (which would have been very effective and probably still highlight-reel stuff) but he chose to "round the corner" to get to his head. Watch the replay. He goes out of his way to come around to the front. There is absolutely no reason to do this other than to make contact with Savard's head. In every other way, the check is more forceful and direct if he hits him from the side. But he doesn't. Why? I think you can make a good argument that every check to the head is an attempt to injure.
For whatever reason, people seem to think that head-shots are a "part of hockey." They're not. They are a part of players trying to hurt each other. There isn't any other reason to hit someone in the head. It's not more spectacular. Sending someone sprawling with a clean shoulder or hip check is what you see on highlight reels. Head-shots are just dangerous, life-threatening, embarrassing for the league, and sickening for the fans. Nobody likes it.
I'm surprised the players' union doesn't speak up. Don't they have a stake in the continued health of their members? Google brain damage retired concussion repeated football hockey and see what comes up. It's not good. Dementia Pugilistica. Onset can take 12-16 years. As a hockey fan, I don't want to see my favorite players sporting drool cups in their forties.
The other "concern" is that head-shots happen by accident all the time, the game moves fast, the player ducks down, etc.. How can you ban something that happens incidentally all the time?
The same way you ban high-sticking. High-sticking, which always involves hitting a player above the shoulder (i.e. neck and head) with your stick, can be a minor, major or match penalty, depending on severity and intent. Or it can be nothing, as with a follow-through of a shot, or if, in the ref's opinion, the player who got hit with the stick was bent over such that the offending player's stick was never "high."
Here, I'll even write the rule for you.
Rule 54.1 - Head Shots
A "head shot" is a body check whose point of contact is above the shoulders of the opponent (i.e. the head or the neck).
A Head Shot penalty shall be imposed on any player or goalkeeper who checks an opponent in the head or the neck. The severity of the penalty, based upon the degree of violence of the impact, shall be at the discretion of the Referee. The onus is on the player (or goalkeeper) to assess whether the player's head or neck would be the point of contact and if so must avoid contact. A check in which the point of contact is not the head or neck, but which causes the opponent's head or neck to be thrown violently into the boards, shall be deemed Boarding. Stick fouls are covered under High-Sticking and Cross-Checking.
54.2 The Referee, at his discretion, may assess a minor penalty, based on the degree of violence of the impact, to a player or goalkeeper guilty of checking an opponent's head or neck.
54.3 When a player or goalkeeper checks the head or neck of an opponent such that injury results, the Referee shall assess a double-minor penalty for all contact that causes an injury, even if accidental or careless, in the opinion of the Referee.
A double-minor may also be assessed, even if there is no injury, if the Referee, at his discretion, determines that the head-shot (even if accidental or careless) was delivered to a player who was not aware of the impending hit, and therefore was unable to protect or defend himself.
54.4 The Referee, at his discretion, may assess a major penalty, based on the degree of violence of the impact.
54.5 The Referee, at his discretion, shall assess a match penalty if, in his judgment, the player or goalkeeper attempted to or deliberately injured his opponent.