Same-sex marriage has been legally recognized in Wyoming since October 21, 2014. Wyoming had previously prohibited state recognition of same-sex marriages by statute since 1977 and had enacted a more explicit ban in 2003. An attempt to enact legislation recognizing domestic partnerships as an alternative to marriage for same-sex couples failed in 2013.
On October 17, 2014, a federal court found the state's ban on same-sex marriage unconstitutional. Its ruling took effect on October 21 when state officials notified the court that they would not appeal the decision.
In 1977, the Wyoming State Legislature passed a ban on same-sex marriage. In 2003, the Wyoming State Legislature passed another ban on same-sex marriage. The statutes read: "marriage is a civil contract between a male and a female person".
Wyoming law also states that "All marriage contracts which are valid by the laws of the country in which contracted are valid in this state" and it does not qualify that statement. (Wyo. Stat. Ann. §20-1-111) Lawsuits have cited these provisions when challenging the state's denial of recognition to same-sex marriages established in other jurisdictions.
On February 22, 2007, a bill to prohibit Wyoming from recognizing same-sex marriages from other states was defeated by one vote in a committee of the Wyoming House of Representatives. In 2009, the House considered an amendment to the state constitution, House Joint Resolution 17, known as the "Defense of Marriage" resolution, defining marriage as a union between a man and a woman. After an intense, emotional debate on the matter, the measure was defeated in a vote by the full House on February 6, with 35 votes against and 25 in favor.
On January 24, 2011, the House passed a bill that would prohibit the state from recognizing same-sex marriages performed outside the state. On February 18, it was passed by the Senate, but after further legislative action it failed. On January 27, 2011, the Senate approved, by two-thirds majority, a constitutional amendment banning same-sex marriage. The proposal died in the House. On January 28, 2011, the House Judiciary Committee voted down a bill legalizing civil unions.
On January 14, 2013, legislators filed a bills establishing same-sex marriage in Wyoming by defining marriage as a civil contract between "two natural persons." On January 28, a House committee defeated the marriage bill 5-4. The House considered the bill and defeated the same-sex marriage bill on February 13, 2013 by a vote of 17-41.
Wyoming Governor Matt Mead said that despite action by the U.S. Supreme Court on October 6, 2014, which left standing as binding precedent on courts in Wyoming rulings of the Tenth Circuit Court of Appeals that found bans on same-sex marriage unconstitutional, the attorney general "will continue to defend Wyoming's constitution defining marriage between a man and a woman", mistakenly referring to the state constitution, which does not define marriage. Clerks in three counties said they had received inquiries about issuing marriage licenses to same-sex couples, but were waiting for a change in state law or an order from a judge.