DENVER — When the US Supreme Court struck down the federal Defense of Marriage Act one year ago, it stopped short of saying states cannot ban gay marriage.
But in a string of 17 straight rulings, judges have argued that the high court’s decision in US v. Windsor means just that: States cannot get in the way of gay couples who want to marry.
The most significant of those findings came Wednesday when the US Court of Appeals for the 10th Circuit in Denver became the first appellate court to weigh in post-Windsor and upheld a ruling that found Utah’s gay marriage ban was unconstitutional.
That decision increases pressure on the high court to make explicit what it did not say last year — that gay couples nationwide have a right to marry.
‘‘This tees it up for possible Supreme Court review,’’ said William Eskridge, a law professor at Yale University. ‘‘When a federal appeals court strikes down a major state law, there is a lot more pressure for the justices to take that.’’
Utah is considering an appeal to the Supreme Court, but there is no guarantee its case will be the one that makes it there. Five other appellate courts are considering similar cases, and the Supreme Court could take any of them.
The earliest the high court could decide a gay marriage case is 2015, but it often waits for a split in appellate courts before considering an issue.
‘‘I don’t know if the Supreme Court is going to wait for a circuit split as long as it usually does,’’ said Nancy Leong, a law professor at the University of Denver, noting the recent judicial unanimity on the issue could make that a long wait. Meanwhile, she said, countless gay couples are eager to marry and less and less tolerant of the slow pace of the courts.
That was on display in Colorado on Thursday, when the county clerk of Boulder issued same-sex marriage licenses even though the 10th Circuit panel stayed its decision pending an appeal. Along with Utah, the 10th Circuit includes Colorado, Kansas, New Mexico, Oklahoma, and Wyoming.
Colorado’s attorney general declared the licenses invalid because the state’s gay marriage prohibition is still the law. But Clerk and Recorder Hillary Hall said she would continue issuing them until a court stops her.
Wednesday’s ruling stressed the urgency of overturning gay marriage bans rather than waiting for new laws.
‘‘Plaintiffs in this case have convinced us that Amendment 3 violates their fundamental right to marry,’’ Judge Carlos Lucero wrote for the majority. ‘‘We may not deny them relief based on a mere preference that their arguments be settled elsewhere.’’
But Judge Paul Kelly argued in his dissent that the 10th Circuit overstepped its authority, and that states should be able to decide who can marry.
‘‘We should resist the temptation to become philosopher-kings, imposing our views under the guise of the 14th Amendment,’’ Kelly wrote.
John Eastman of the National Organization for Marriage argued the dissent increases the likelihood the Supreme Court will weigh in. Eastman, a law professor at Chapman University in Southern California, said he doubts there are five votes on the high court ‘‘to impose marriage on the 30-some states that don’t have it now.’’
On the eve of the last year’s Windsor ruling, Justices Ruth Bader Ginsburg and Stephen Breyer, talked about the importance of not having the court get too far ahead of the country in ruling on major social issues.