Lawmakers in the southern Mexico state of Oaxaca have approved changing the civil code to authorize same-sex marriage.

A statement from the state congress says marriage will now be defined as a “civil contract celebrated between two persons, who unite to realize a life in common and provide each other respect, equality and mutual help.”

With Wednesday’s vote, about 20 of Mexico’s 31 states plus Mexico City have codified same-sex marriage into law. Read more via AP

Mexico's Wild Ride to Marriage Equality

Eighteen of Mexico's 31 states and the federal capital Mexico City have marriage equality and same-sex couples can marry in the other 13 states if they go to a federal judge and get a personalized injunction (amparo), a process that is time-consuming and requires paying a lawyer for help. The judge cannot refuse the amparo.

The requirement on judges resulted from a 2015 ruling by the Supreme Court of Justice of the Nation (SCJN) that declared all bans on marriage equality unconstitutional. The Supreme Court, however, has no power to end all states' bans simultaneously, and can only force individual states' bans out of existence in specific situations.