Mexico Supreme Court rules for marriage equality

In a unanimous decision yesterday, Mexico's Supreme Court overturned a ban on same-sex marriage in the southern state of Oaxaca, saying the law was unconstitutional and "violates the principle of equality."

The Associated Press reports the ruling came after three couples filed a lawsuit against the state, and makes Oaxaca the second locale after Mexico City to have legal same-sex marriage. 

Mexico City legalized marriage equality in 2010. 

The Oaxaca ruling may not have been soley based in Mexican law, however. 

Salon.com's J. Lester Feder wrote after the decision was announced that the Court may have been influenced by international law, namely the Inter-American Court and the American Convention on Human Rights, which “prohibits … any rule, act, or discriminatory practice based on sexual orientation.”

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"This ruling from an international court — whose verdicts count as legal precedents in Mexican courts — expanded the significance of what the Mexican Supreme Court had already found when it upheld the Mexico City marriage law," said a lawyer who worked on the case, Geraldina de la Vega. De la Vega said to Salon that together the cases [in Mexico City and internationally] "would have a big impact on what the court 'pronounces on the scope of family protections' under Mexican law."

By allowing the Inter-American Court of Human Rights [IACHR] jurisdiction, Mexico may have unintentionally bust open the doors for marriage equality in a significant number of Latin American countries. Twenty-four of the 35 countries of the Organization of American States, the organization that oversees the court, are supposedly bound by the Human Rights Convention and decisions made by the Inter-American Court of Human Rights. (The US isn't one of those countries.)

Chile has also seen important LGBT rights rulings by the Inter-American Court trickle down. In March, a Judge named Karen Atala who lost custody of her two children because of her sexual orientation won her case through the IACHR.

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In a landmark ruling that defined the rights of gay parents across Latin America "reiterated in no uncertain terms that a parent's sexual orientation cannot be a basis for a denial of custody," wrote American University professor Nancy Polikoff on her blog after the ruling. "Before ruling specifically on Atala's case, the Court ruled categorically that discrimination on the basis of sexual orientation violates the right to equality and non-discrimination contained in the American Convention on Human Rights."

Another Chilean case is making its way through the system as well, a September filing for marriage equality in that country. 

For more of GlobalPost's coverage of marriage equality, check out our Special Report "The Rainbow Struggle: A Global Battle Over Gay Rights."