A federal judge on Friday (7 November) struck down Missouri's ban on gay marriage that was passed by voters in the Midwestern state 10 years ago.
US District Court Judge Ortrie D. Smith ruled that the ban is unconstitutional and that that same-sex couples can obtain marriage licenses.
The state has said it will appeal.
Smith's ruling comes two days after same-sex marriage marriage licenses began being issued in the city of St. Louis where a state judge lifted the ban.
Smith's decision applies to the entire state.