LINCOLN, Neb. (AP) — Gov. Dave Heineman says Nebraska will defend itself against an expected legal challenge to the state’s constitutional ban on same-sex marriage.

The Republican governor said Wednesday that Nebraska will “not take a pass” on the lawsuit, which the American Civil Liberties Union of Nebraska plans to file next week.

Heineman notes that voters in 2000 overwhelmingly approved a constitutional measure, which defined marriage as the union of one man and one woman. The measure prohibits same-sex marriage, civil unions and legalized domestic partnerships.

Danielle Conrad, executive director of the ACLU of Nebraska, says the legal and political landscape has changed rapidly, and the issue is one of fairness.

A federal judge struck down Nebraska’s measure in 2005, but a three-judge federal appeals court panel reinstated it the following year.