Kentucky officials must recognize legally valid same-sex marriages performed in one of the 17 states that allow them, a federal judge ruled on Wednesday, striking down part of the Bluegrass State’s law prohibiting gay couples from marrying.

U.S. District Judge John G. Heyburn II, a President George H.W. Bush appointee, wrote in a 23-page ruling that “Kentucky’s laws treat gay and lesbian persons differently in a way that demeans them.” He joins nine other federal and state courts to have invalidated bans on same-sex marriage, the Courier-Journal notes.

Kentucky was one of the first states to enact a constitutional amendment both barring gay couples from marrying in the state, and forbidding government officials and agencies from honoring same-sex marriages performed outside of the state. Voters overwhelmingly approved the amendment in 2004 by 74%. The state is still allowed to deny gay couples marriage licenses, as that question was not part of the lawsuit.

Rejecting arguments from Kentucky attorneys that the ban served a “legitimate government interest of preserving the state’s institution of traditional marriage,” Heyburn noted that the U.S. Supreme Court ruled against tradition when it struck down state bans on interracial marriages. He also dismissed arguments from the Family Foundation of Kentucky, another party defending the ban, that recognizing same-sex marriages would undermine the institution’s role of promoting procreation.

“No one has offered any evidence that recognizing same-sex marriages will harm opposite-sex marriages,” wrote Heyburn.

The suit was filed on behalf of four gay couples who were married outside of Kentucky. It comes amid a wave of similar challenges to state bans across the country–including, most recently, one in Louisiana, and one in Missouri. Both were announced this week.

A federal hearing in Texas against that state’s same-sex marriage ban also began on Wednesday. It marks the first attempt to topple such laws in the deep South.