CHICAGO — A federal appeals court ruled Thursday that same-sex marriage bans in Wisconsin and Indiana violate the US Constitution, another in a series of courtroom wins for gay-marriage advocates.
The unanimous decision by the three-judge panel of the US Court of Appeals for the Seventh Circuit in Chicago criticized the justifications both states gave for the bans, several times singling out the argument that marriage between a man and a woman is tradition. There are, the court noted, good and bad traditions.
‘‘Bad traditions that are historical realities such as cannibalism, foot-binding, and suttee, and traditions that from a public-policy standpoint are neither good nor bad — such as trick-or-treating on Halloween,’’ it said. ‘‘Tradition per se therefore cannot be a lawful ground for discrimination, regardless of the age of the tradition.’’
Same-sex marriage is legal in 19 states and the District of Columbia. Bans that have been overturned in some other states continue to make their way through the courts. Since last year, the vast majority of federal rulings have found gay marriage bans unconstitutional.
Wisconsin’s attorney general, J.B Van Hollen, said he would appeal Thursday’s ruling to the US Supreme Court.
The Wisconsin and Indiana cases shifted to Chicago after attorneys general in the states appealed separate lower court rulings in June that tossed the bans. The Seventh Circuit stayed those rulings pending its own decision on the cases.
During the interim between the bans being struck down and the order reinstating them as the appeals process ran its course, hundreds of gay couple in both states rushed to marry. Those marriages could have been jeopardized had the Seventh Circuit restored the bans.
Judge Richard Posner, an appointee of President Reagan, a Republican, in 1981, wrote Thursday’s opinion for the panel. During oral arguments, it was Posner who fired the toughest questions at defenders of the bans, often expressing exasperation at their answers.
The ruling echoes his comments in oral arguments that ‘‘hate’’ underpinned such bans, saying, ‘‘Homosexuals are among the most stigmatized, misunderstood, and discriminated-against minorities in the history of the world.’’
The states argued that the prohibitions helped foster a centuries-old tradition of marriage between men and women.
Thursday’s opinion went back to that issue repeatedly, noting that some traditions, such as shaking hands or men wearing ties, may ‘‘seem silly’’ but ‘‘are at least harmless.’’
That, though, is not the case when it comes to gay-marriage bans, the court said.
‘‘If no social benefit is conferred by a tradition and it is written into law and it discriminates against a number of people and does them harm beyond just offending them, it is not just a harmless anachronism; it is a violation of the equal protection clause,’’ the opinion says.
A constitutional amendment approved in 2006 by voters banned gay marriage in Wisconsin, while state law prohibited it in Indiana. Neither state recognized same-sex marriages done in other states.