Rape will usualy boil down to a he said - she said scenario. There is nothing you can do to prevent this. It's the nature of the aqusation. This does not make it any less a crime, just harder to prove.
Point of order: The "he said, she said" scenario is an ACCUSATION, not a crime. A crime MAY have occurred, a misunderstanding MAY have occurred, or a false accusation MAY be occuring (i.e., another crime). Healthy skepticism is the order of the day, and granting that the "he said, she said" scenario isn't "any less of a crime, just harder to prove", violates that skepticism.
Now, to the subject of rape shield laws and all that: they are wrong. Period. If society and the criminal justice are going to take the tack that rape is an especially heinous crime, then the correct place to account for the gravity of offense is in the SENTENCING, not prosecution. Rape shield laws are predicated on the notion that a crime DID TAKE PLACE, which, legally speaking, is not established until "Guilty."
Impaired Consent: if a woman gets drunk, and she doesn't remember what happened, tough. She got drunk on her own. She
voluntarily vacated her faculties. Ditto if SHE takes drugs. On the other hand, if a man slips her a roofie then rapes her, AND it is proven beyond a reasonable doubt, execute him. Plain and simple.
The essential point is that the "rape as heinous crime" crowd consider it so heinous because it is an assault on the very personhood of the victim. Operating under that logic, then we must also RESPECT the personhood of the victim, and accord them full responsibility for their own actions. If a person is "overpersuaded", too bad, they're responsible for
getting up and leaving. If they have too many drinks,
they're responsible for having too many. Many of the same folks who find a sober man guilty of "raping" a drunk woman based on "he said, she said" will send a DUI to the bighouse in a New York minute, i.e., double standard. The only reason for the double standard is the unspoken contention that women are
not fully responsible for their sexual behavior, i.e., they aren't full people. stoopid, stoopid, stoopid, especially when you consider that in these cases, ESPECIALLY if both parties were drinking, the man is required to be responsible for BOTH.