To be honest, that principle hasn’t been always consistently applied. It obviously applied to cases of murder where the victim had no one to talk in their name, but for example, the increasing sensitivity to cases of domestic violence, once those have been considered less acceptable by society, and therefore more often reported, put into question the integrity of usual doctrines: in many cases, the victim of those violences is under the influence of the perpetrator.
The fun part being that, once the law community came aware of that issue, they had to document about BDSM practices, in order to be able to distinguish them from abuses. Even if they were uptight and reluctant.
