Mexican Same Sex Marriage Case

The Legislative Assembly of the Federal District of Mexico (an area largely encompassed by Mexico City) amended Articles 146 and 391 of the Federal District Civil Code. The amendments redefined marriage as a “union of two people.” This amendment effectively granted same-sex couples within the Federal District access to marriage within the district. The attorney general brought an action of unconstitutionality to the Mexico Supreme Court to invalidate the amendments to Articles 146 and 391 of the Federal District Civil Code. The attorney general asserted that the Legislative Assembly’s arguments in support of the amendments did not correspond with the Constitution of Mexico. The attorney general also asserted that the Legislative Assembly had failed to demonstrate that the current laws encouraged discrimination against certain groups of people like LGBT people, particularly considering the recent laws on domestic partnerships for same-sex couples. The attorney general argued, therefore, that the amendments to the Federal District Civil Code violated Article 16 of the constitution, as the Legislative Assembly had failed to provide arguments for the amendments with the required proportional and objective reasonableness. The attorney general further asserted that the legislature lacked the competency to outline a definition of marriage that included same-sex couples, arguing that marriage and family were fixed, fundamental concepts under Mexican law.