The problem is not with unconscious victims.  Logic dictates--and the Supreme Court has confirmed--that an unconscious person cannot consent to anything, even if such consent was previously given (just as a general power of attorney becomes invalid when the person loses the ability to revoke it).  There's no need to write the obvious into the law.  On the other hand, a grey area arises when a person is conscious but her consent is impaired by intoxication.  Does "yes" automatically mean "no" if she is drunk?  What degree of impairment is required?   If the accused is also drunk, should this mitigate his offence?  In a situation where both parties have been drinking (which is often the case), what is the test in determining whether the accused should have known that "yes" means "no"?  And if the victim's previous sex life is off-limits, should the accused's previous sex life (including previous sexual assault accusations or convictions) be similarly off-limits?