11Administering a substance for sexual purposesS
(1)If a person (“A”) intentionally administers a substance to, or causes a substance to be taken by, another person (“B”)—
(a)without B knowing, and
(b)without any reasonable belief that B knows,
and does so for the purpose of stupefying or overpowering B, so as to enable any person to engage in a sexual activity which involves B, then A commits an offence, to be known as the offence of administering a substance for sexual purposes.
(2)For the purposes of subsection (1), if A, whether by act or omission, induces in B a reasonable belief that the substance administered or taken is (either or both)—
(a)of a substantially lesser strength, or
(b)in a substantially lesser quantity,
than it is, any knowledge which B has (or belief as to knowledge which B has) that it is being administered or taken is to be disregarded.