I have seen a number of tweets recently, justifying a man having sex with a woman because he “reasonably believes” she has consented.
In the face of it, this seems OK. The law does in fact say person A has only raped person B if person “A does not reasonably believe that B consents.”
However, I think that in many cases, the posters misunderstand the meaning of the word “reasonably”
The law was changed relatively recently (around 2003), to add the requirement for “reasonable” belief in addition to “honest” belief. The problem with the previous wording (honest) was that it was possible for a rapist to mount a defence based on the fact that he honestly believed that consent was given – even though it was completely unreasonable for him to believe so.
The word “reasonably” is now in place, so that the courts can decide if that belief is reasonable. It doesn’t matter if the rapist believes it to be reasonable – it is what the court decides that matters.
If a women is frightened/drunk/drugged/coereced/browbeaten/tricked/etc/etc/etc into accepting the advances of the rapist, or the rapist believes he has consent because of the (irrelevant) behaviour of the victim (eg state of dress, accepted invite to room, “was all over him” etc) the court can decide that the rapist does not “reasonably believe” consent is given, even though he may claim to “honestly believe” so.