(1) A person who has sexual intercourse with another person who—
(a) is not the spouse of the first-mentioned person; and
(b) is 12 years of age or more but has not attained the age of 16 years,
commits an offence and is liable on conviction on indictment to imprisonment for 15 years.
(2) It is a defence to a charge under this section if the person charged proves that—
(a) the other person consented; and
(b) the person charged—
(i) was not more than 21 years of age at the time of the commission of the offence and has not been previously charged with the same or similar offence, and
(ii) had reasonable cause to believe and did believe that the other person was 16 years of age or more.
(3) Subsection (2) shall not apply if it is proved that the consent was obtained by false or fraudulent representation as to the nature of the act.
(4) Except as provided in subsection (2), it is no defence to a charge under this section that the person consented or that the person charged believed that the person was 16 years of age or more.
(5) If a marriage is declared invalid by a Court of competent jurisdiction the invalidity does not make a person guilty of an offence under this section because that person has sexual intercourse with a person who he or she or she believes to be his or her or her spouse, and has reasonable cause for the belief.