The crux of the problem is that most sexual acts take place in private - even rape - so proof is very hard to obtain. There are only two people involved and it is one word against the other. The only valid evidence might be that of force - i.e. evidence of injury of some kind to the victim.
I no more want a man to be wrongly convicted than I want a woman to suffer a sexual assault and the perpetrator go free. Both are fundamentally wrong. And the idea that a man should face years in jail on the "balance of probabilties" is shocking. A life ruined on the basis of guesswork. Equally it is dreadful that someone who has committed rape should go free.
Cases of rape are seldom clear cut and a sense of outrage on behalf of a female alleged victim should not lead to a dilution of the rules of proof that are the basis of our system of justice.
In this particular case it is not to the young man's credit that he uses his Westminster office for sex, but there is a difference between lack of judgement and rape.
No-one knows the truth except the two people involved.