Legally, drunkenness does not mean that a woman is incapable of consent

Another controversial rape-and-consent case has been in the Canadian news recently, after a Nova Scotia provincial court judge acquitted a Halifax taxi driver on the grounds that the drunk woman in the back of the car may have consented, or was at least capable of consenting.
The thing is, from a purely legal point of view, the judge was probably actually right. The woman in the taxi was blind drunk and was found nearly naked and unconscious in the back seat. She herself does not remember a thing about the incident. While she would have been legally incapable of consenting to sex while unconscious, there remains the possibility that she might have given consent while still conscious, and the fact that the woman was very drunk does not in itself mean that she was legally incapable of consent.
The problem arises, then, that it is also possible, or at least conceivable, that someone could be so drunk that they were effectively incapable of consenting. There is no line that can be struck that the legal profession can use to establish this definitively, and so the judge in this case was obliged to give the taxi driver (who, as it happens, has been accused twice before of this kind of predatory behaviour with drunk women) the benefit of the doubt.
Meanwhile, the sexual targeting of women who are drunk, passed out, asleep, or mentally disabled, continues to go on, and it represents a significant category of sexual assault offences. The law really needs to address the issue, and put some legal obstacles in the way of such sexual predators. But it seems that their hands are tied.