Lord Hailsham said it doesn’t matter if the mistaken belief is based on unreasonable grounds (weaker than ruling in Tolson) since it is still a belief in consent. The mens rea is not caring whether or not there is consent. In this case Ds believed that there was consent. Lord Cross says that an “honest” rather than “reasonable” belief is enough to negate fault and therefore reason for liability. Lord Simon, dissenting, said that there has to be a balance struck between victim and defendant: on the one hand a reasonable belief, as well as requirement of honesty should exculpate D since he is and ought to be satisfied that the circumstances indicate that he commits no crime. To leave out “reasonable” would allow people who simply “don’t care” as to their victim’s feelings to be freed from blame. It also exculpates people who don’t bother to make adequate inquiry.
