In response to nooka, I am not a rape apologist and have no interest in exonerating rapists.
People choose to have sex for all sorts of reasons, often, sadly when they'd rather not. I have no doubt that most of the time that choice is clear and the majority of the time it is easy for everyone to distinguish consensual but unwanted sex from rape.
Having said that, I'm not at all convinced that there aren't times when women allow sex to happen without giving verbal consent to it or participating much, but without signalling that they want it to stop, either. Far from exonerating men, defining sex as rape in those circumstances would be raising the bar.
IMO it simply doesn't go far enough to say that men should check verbally if there's any reason to doubt. Although I do think there's a responsibility on their shoulders to pick up on a lack of enthusiasm/participation where it can reasonably be expected of them, the reality is that some men may not realise there was any reason for doubt and may be working with a completely different set of cultural expectations. Such as, for example, assuming that the woman has an expectation that events unfold towards the sex act unless she says she doesn't want to carry on.
Men may also believe they are expected to act in a way that they have been told that women will find attractive and the messages about what women want are very, very misleading; our culture has very loudly and unhelpfully informed a generation of men that woman want to be dominated and mastered. I agree that most of the time this won't create a problem because most of us understand the concept of role playing but there are times, especially when the woman is not practiced at unequivocally stating her wishes, when both people have had a drink and they're not well known to each other, when perhaps it could.
I think it may, in some circumstances (perhaps rarely) be considerably more complex than 'would you like a cup of tea' - because there is only one way to work out if someone else would like tea and women don't tend to feel under complex cultural pressure to try to like tea, even if they don't want any. In thinking this through, I have no desire to remove the label from a rapist or trivialise the offence.
Brock's offence was heinous and it underlines, to me, the importance of understanding, without being afraid of where it will take us, all there is to understand about the cultural setting that gives rise to rape and exactly what is happening when women feel pressured to tolerate or participate in any kind of sexual coercion in our society. That does not need to be at odds with empowering women in sexual encounters, empowering victims or teaching men to seek nothing less than enthusiastic consent.
Women aren't blameless in adding to the confusion - magazines often have articles on sex that encourage women to go along with it if their partners are in the mood for sex, even if they don't want it, on the principle that if you weren't in the mood to begin with, you likely will be later. So the message that you ought to have unwanted sex is encouraged. In such circumstances, is there always a clear dividing line between 'I agreed to go along with this; it was consensual' and 'I let it happen but it happened to me - therefore I was raped'. Genuine question.