A person (A) commits an offence if—
he intentionally engages in an activity,
the activity is sexual,
for the purpose of obtaining sexual gratification, he engages in it—
when another person (B) is present or is in a place from which A can be observed, and
knowing or believing that B is aware, or intending that B should be aware, that he is engaging in it,
B has a mental disorder,
A knows or could reasonably be expected to know that B has a mental disorder, and
A is involved in B's care in a way that falls within section 42.
Where in proceedings for an offence under this section it is proved that the other person had a mental disorder, it is to be taken that the defendant knew or could reasonably have been expected to know that that person had a mental disorder unless sufficient evidence is adduced to raise an issue as to whether he knew or could reasonably have been expected to know it.
A person guilty of an offence under this section is liable—
on summary conviction, to imprisonment for a term not exceeding 6 months or a fine not exceeding the statutory maximum or both;
on conviction on indictment, to imprisonment for a term not exceeding 7 years.