RICHMOND, Va. — Virginia’s attorney general has concluded that the state’s ban on gay marriage is unconstitutional and he will no longer defend it in federal lawsuits challenging it, his office said Thursday.

In an email to The Associated Press, Michael Kelly, a spokesman for Attorney General Mark Herring, said the state will instead side with the plaintiffs who are seeking to have the ban struck down.

Additional Photos

Virginia Attorney General Mark Herring says he will no longer defend the state’s ban on same-sex marriage in federal lawsuits challenging it. The Associated Press / Dec. 18, 2013, file photo

Herring planned to file a brief Thursday morning with the federal court in Norfolk, where one of the lawsuits is being heard, notifying the court of the state’s change in position in the case, Kelly said.

The attorney general decided the ban was unconstitutional after a thorough legal review of the matter, Kelly said.

Virginia has emerged as a critical state in the nationwide fight for gay marriage. The state’s shift comes on the heels of recent court rulings in which federal judges struck down gay marriage bans in Utah and Oklahoma.

With the election of Gov. Terry McAuliffe and Herring as attorney general, Virginia made a hairpin turn away from the socially conservative officeholders they succeeded, particularly Republican Attorney General Ken Cuccinelli, an activist on social issues such as abortion and gay marriage. Herring had campaigned, in part, on marriage equality, and McAuliffe issued an executive order on inauguration day prohibiting discrimination against state employees who are gay.

Virginia voters approved the same-sex marriage ban 57 percent to 43 percent in 2006. But a Quinnipiac University poll in July found that 50 percent of registered Virginia voters support same-sex marriage, while 43 percent oppose it. The survey’s margin of error was plus or minus 3.1 percentage points.

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