Commentary on Sections Part 1: Sexual Offences Section 29: Sections 25 and 26: sexual relationships which pre-date family relationships
60.This section provides A with a defence to the offences under sections 25 and 26 if he can prove that his sexual relationship with the child pre-dated the start of the familial relationship as defined in section 27. Thus, for example, where two divorced people meet because their respective 16 and 17 year old children are engaged in a sexual relationship and the parents decide to marry, if all four persons were to move into the same household the criminal law would not interfere in the ongoing sexual relationship between the children, even though they would otherwise have been brought within the scope of the offence. This defence is not available where A and the child are related as set out in section 27(2) (whether by blood or adoption). The effect of subsection (2) is to limit this to the situation where the sexual relationship was lawful so it would not cover for example a relationship with a child of under 16.