In the UK and until recently
, rape was the only serious crime that may
(not "must") rely upon the personal opinion of two independent persons. Robbery requires there to be property taken but rape does not have a requirement for physical evidence
(although it helps.)
For a conviction, there has to be "mens rea
": the accused must have a genuine and substantiated belief that the action was wrong. The victim must, either never have given consent by word, deed or normal lack of action or
at any time, before during or after, have withdrawn consent.
From the Wiki link:
In a 2000 research article from the Home Office, in England and Wales, around 1 in 20 women (5%) said that they had been raped at some point in their life from the age of 16 beyond.
In 2011, the US Centers for Disease Control found that "nearly 20% of all women" suffered rape or attempted rape sometime in their life. More than a third of the victims were raped before the age of 18.
Many rapes by males against females are unreported because of "fear of reprisal from the assailant" and because of "shame...and deep-seated cultural notions that the woman is somehow to blame".  Researchers from the University of Surrey estimate that approximately 1 in 7 rapes by males against females are reported.
From "The Independent" http://www.independent.co.uk/news/uk/crime/100000-assaults-1000-rapists-sentenced-shockingly-low-conviction-rates-revealed-8446058.html
"100,000 assaults. 1,000 rapists sentenced. Shockingly low conviction rates revealed.
Taking these two statistics together, can we conclude that only one in a thousand accusations of rape is substantiated, so the "(5%) [who] said that they had been raped" reduces to 0.005%? Or is it a misconception of what rape is?
I think that we are dealing with a problem that we know exists but we have absolutely no idea of the figures. All that we have left is our emotions.
Perhaps we could compare rape to common assault and ask, "How many assaults are there, including unreported ones and how many of the reported cases end in a conviction?" but this is not the same. The essence of assault is no person is ever willingly and knowingly assaulted, whereas we know that most persons are willing to have sexual intercourse at some time. These circumstances then create a similar but not identical instance: Assume that you attend a college sports meeting and watch the high jump from a distance. You know the winner so you go over and, as his back is turned, you slap him heartily on it and say, "Well done!" The winner turns round and he is a complete stranger - you don't know him. Did you assault him? If it had
been your friend, was there an implied consent to be slapped? - And if so, is that true even if the slap turned out harder than you intended? How much harder?
With assault, no victim thinks "Oh yes, it's OK if he hits me." and then, shortly before, during, or only after the blow, do they say, "I didn't want any of that! That was assault."
Added to this, there is the fact that (at least in the UK) if you were "of previously good character" and you assault (non-aggravated) someone, you'll probably be fined. In the same circumstances for rape, an immediate sentence of at least 5 years will ensue.
Cases of malicious false reporting of rape are not unknown and (IIRC) at least three women in the UK are serving time for this offence. I can't say that I have heard of a case of malicious false reporting of assault.
I was involved in gathering information of "unreported crime". In my case, it was (i) not a crime against the person and (ii) victimless and was therefore easier to assess as there was no "personal opinion" but, even then, the final figure was, of necessity, an approximation.
The lessons are:
1. Rape is easy to detect in some cases
2. The consequences of being raped and of being wrongly convicted for rape are equally serious
3. We have no idea of the number of rapes
4. The laws on rape are probably the best we are likely to have because, at the moment, two personal opinions rely upon the personal opinions of a jury.
5. Secure acceptance that education, support and protection are given in the case of "Many rapes by males against females are unreported because of "fear of reprisal from the assailant" and because of "shame...and deep-seated cultural notions that the woman is somehow to blame."
6. There are no easy answers that are both effective and just.