Michigan's ban on gay marriage is unconstitutional, a federal judge said Friday as he struck down a law that was widely embraced by voters a decade ago -- the latest in a recent series of decisions overturning similar laws across the country.

U.S. District Judge Bernard Friedman announced his ruling after a rare two-week trial that mostly focused on the impact of same-sex parenting on children.

There was no indication that the judge was suspending his decision. Attorney General Bill Schuette said he was immediately filing a request with a federal appeals court to suspend Friedman's decision and prevent same-sex couples from immediately marrying. The decision was released shortly after 5 p.m., when most county clerk offices in Michigan were closed. Clerks issue marriage licenses.

Seventeen states and the District of Columbia issue licenses for same-sex marriage. Since December, bans on gay marriage have been overturned in Texas, Utah, Oklahoma and Virginia, but appeals have put those cases on hold.

Two Detroit-area nurses, Jayne Rowse and April DeBoer, want to get married, but the original purpose of their 2012 lawsuit was to overturn Michigan's ban on joint adoptions by same-sex couples.

They are raising three adopted children with special needs at their Hazel Park home. But they can't jointly adopt each other's kids because joint adoption in the state is tied exclusively to marriage.

Attorney Dana Nessel read portions of the decision on live TV at the kitchen table in the DeBoer-Rowse home.

"It's unbelievable," DeBoer said on television. "We got our day in court. We won."

Rowse, 49, and DeBoer, 42, didn't testify, and the trial had nothing to do with their relationship. In fact, attorneys for the state told the judge that they are great parents.

Instead, the state urged the judge to respect the results of a 2004 election in which 59 percent of voters said marriage in Michigan can only be between a man and a woman. Conservative scholars also questioned the impact of same-sex parenting on children.

But experts testifying for Rowse and DeBoer said there were no differences between the kids of same-sex couples and the children raised by a man and woman. And the University of Texas took the extraordinary step of disavowing the testimony of sociology professor Mark Regnerus, who was a witness for Michigan.