Sometimes controversies are conversations of the deaf. That may be because the two positions are not really contradictory, but the two sides keep on repeating their positions as if one does deny the other. Take the different reactions to England's (and Wales', just) recent riots and looting. Anyone who tried to link the events to poverty, to vast income diferentials or to unrelieved consumerism has got jumped on by people accusing them of being soft on crime and excusing violent or selfish acts.
But when historians try to find explanations for the rise to power of the Nazis in Germany, perhaps trying to explain why some people became enthusiastic Nazis, they're not accused of excusing Nazism: it's generally regarded as a sensible thing to do, in order to try to make sure it doesn't happen again.
Looting is wrong and kicking an old man to death is downright evil, but it surely makes sense to ask ourselves why this could happen, why it happened in some places and not others, and how to make it less likely in future.
Similar illogical arguments can happen over sexual assault and indeed any assault. A rapist or a violent robber is totally wrong and totally responsible for his actions. If the victim was drunk and refused the offer of a place in a taxi with friends, it's entirely sensible to point out to others that this greatly increased the chances of an attack (I'm not talking here about stupid comments about jeans etc). To point this out is not to reduce the culpability of the attacker at all. What we seem to be doing here is importing the insurance industry idea of percentages of responsibility (the accident was 60% your fault and 40% his) into an area where it doesn't belong. What I do is 100% my responsibility.