Section 2B Intercourse with step-child.

Any step-parent or former step-parent who has sexual intercourse with his or her step-child or former step-child shall be guilty of an offence if that step-child is either under the age of 21 or has at any time before attaining the age of 18 lived in the same household and been treated as a child of his or her family, unless the accused proves that he or she—

1. (a)

   did not know and had no reason to suspect that the person with whom he or she had sexual intercourse was a step-child or former step-child; or

2. (b)

   believed on reasonable grounds that that person was of or over the age of 21 years; or

3. (c)

   did not consent to have sexual intercourse or to have sexual intercourse with that person; or

4. (d)

   was married to that person, at the time when the sexual intercourse took place, by a marriage entered into outside Scotland and recognised as valid by Scots law.