Regina v B (M) [2013] EWCA Crim 3; [2013] WLR (D) 43
“Under the rule in section 1 of the Sexual Offences Act 2003, unless the defendant’s state of mind amounted to insanity in law, beliefs in consent arising from conditions such as delusional psychotic illness or personality disorders had to be judged by objective standards of reasonableness and not by taking into account a mental disorder which induced a belief which could not reasonably arise without it.”
WLR Daily, 31st February 2013
Source: www.iclr.co.uk