The top court's decision brings Mexico closer to a small group of Latin American nations -- Argentina, Brazil and Uruguay -- that allow gay marriage.
The ruling, which was quietly issued on June 3 and only became known on Friday, says that it is unconstitutional for Mexican states to ban same-sex marriage.
While the "jurisprudence" issued by the court does not oblige states to change their laws, it requires courts to rule in favor of same-sex couples whose marriages were rejected.
"It is a very important step forward for us because it involves access to rights and it's a decision that paves the way for a cultural change, for diverse families to be more visible," Tania Leon, a member of the Fundacion Arcoiris gay rights group, told AFP.
"There is still much to do," Leon said, because gays and lesbian still the targets of discrimination.
Mexico City made history when it legalized same-sex marriage in 2007.
It was followed by the states of Quintana Roo and Coahuila, but Mexico's 29 other federal entities define marriage as a union between a man and a woman.
The Supreme Court ruled: "Seeking to link the requirements for marriage to sexual preference... to procreation is discriminatory, because it unjustifiably excludes from marriage homosexual couples that are in similar condition as heterosexual couples."
The nation's top tribunal has chipped away at laws banning gay marriage in recent years.
A previous ruling allowed gays and lesbians to ask courts to recognize their marriages. The latest decree orders judges to automatically rule in favor of same-sex couples.
The governmental National Council to Prevent Discrimination hailed the ruling as "a historic step in recognizing the rights of the sexually diverse community."
source: www.abs-cbnnews.com
