Northern Ireland (Executive Formation etc) Act 2019, §8 (Same-sex marriage)
This Act legalized same-sex marriage in Northern Ireland. §8(1) of the Act requires the Secretary of State to make regulations in respect of same sex marriage, to come into force on or before 13 January 2020, specifically to make provision so that two persons of the same sex are eligible to marry and two persons who are not of the same sex may form a civil partnership in Northern Ireland.