Daniel Mears, Detroit News (AP) From left, April DeBoer and Jayne Rowse with DeBoer's attorney Dana Nessel enter Federal Court in Detroit, Tuesday, Feb. 25, 2014 before a trial that could overturn Michigan's ban on gay marriage. Photo:

Daniel Mears, Detroit News (AP) From left, April DeBoer and Jayne Rowse with DeBoer's attorney Dana Nessel enter Federal Court in Detroit, Tuesday, Feb. 25, 2014 before a trial that could overturn Michigan's ban on gay marriage. Photo:

Updated: 5:00 p.m. EST

DETROIT — Children need good parents, no matter their gender or sexual orientation, a psychologist testified Tuesday at a trial challenging Michigan’s ban on gay marriage.

David Brodzinsky, an expert in adoption and foster care and a former Rutgers University professor, said there are no “discernible differences” in children who are raised by same-sex couples and youth raised by heterosexuals.

“It’s not the gender of the parents that’s the key. It’s the quality of the parenting,” said Brodzinsky, based in Oakland, Calif.

Two Detroit-area nurses who together are raising three adopted children are seeking to overturn a Michigan constitutional amendment that recognizes marriage only between a man and a woman. Jayne Rowse, 49, and April DeBoer, 42, also are targeting a state law that prevents them from jointly adopting each other’s kids because they’re not married.

It’s the first U.S. trial over a gay-marriage ban since a California trial in 2010, although federal judges in other ways recently have struck down similar bans in Utah, Oklahoma and Virginia. At least 17 states and the District of Columbia now allow marriage by same-sex couples.

The Michigan trial, which could last two weeks, will have testimony from experts in areas of economics, marriage and child-rearing. The issue for U.S. District Judge Bernard Friedman is whether there’s a rational state interest in restricting marriage to a man and a woman.

The state attorney general’s office is defending the 2004 constitutional amendment, which was approved by 59 percent of voters.

To scratch the amendment, the judge would have to find that it’s “inconsequential” to have children raised by a man and a woman, Assistant Attorney General Kristin Heyse said in her opening remarks.

“This court should not be rushed to embrace a position that mothers and fathers are interchangeable,” she said.

The election result nearly a decade ago, Heyse said, “was not a whim of the few but a vote of the majority, the will of the people.”

Rowse and DeBoer claim the amendment violates their rights under the Equal Protection Clause of the U.S. Constitution. They are raising three adopted children with special needs at their Hazel Park home.

“Nothing says family like a marriage license,” DeBoer told reporters before entering the courthouse hand-in-hand with Rowse, her partner of eight years.

They walked past more than a dozen people who marched peacefully on the sidewalk with signs declaring, “We support traditional marriage. One man, one woman.”

The couple’s attorney, Carole Stanyar, said she would present evidence to show there’s no rational basis to single out gays and lesbians who want to marry — a key legal standard in the case.

“We would like this to be the last trial in America where same-sex parents will have to defend themselves,” she told the judge.

Under questioning by Stanyar, Brodzinsky noted that the American Psychological Association has said there’s no scientific basis for believing that gays and lesbians are unfit parents based on their sexual orientation. He said there are benefits to kids if their same-sex parents can marry.

“It affords them what sociologists call social capital, recognition,” Brodzinsky said. “This is a real family — we’re no different than anyone else.”

A Stanford University sociology professor, Michael Rosenfeld, said he looked at census data of children living with same-sex parents.

“Progress through school … is just as good as children raised by any other family,” he testified.

Follow the case: DeBoer v. Snyder.

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