I assume the criminal law (as oppose to the laws of the game) that Clark would be in breach of would be under offences against the person. The issue of consent is dealt with in R v Brown (1993) in a which a group of sado masichists went at each other with 6 inch nails in the unmentionables. It was held that no person can consent to assault. On a less high horse note I think it is vital that the game governs itself and is seen to be doing so. Players going to the police about other players actions on the field wouls set a dangerous precedent and allow those who are not familiar with the culture of Rugby to make important decisions and affect the game adversely. Just my humble opinion but I haven't just had some psycho try to break my arm.