The US supreme court signalled a sweeping expansion of gay rights across America on Monday, declining to hear appeals from five states seeking to uphold bans on same-sex marriage and setting a course for legalisation in a majority of states in the union.

The court’s unexpected decision to slam the door on pending appeals meant there will be no imminent ruling on the constitutionality of gay marriage nationwide. But it had the dramatic effect of clearing a way for its rapid expansion to 30 states and the District of Columbia.

In some of the most conservative states in the country, county clerks issued marriage licences within hours of the justices’ terse announcement on Monday.

The decision had an immediate impact on five states. Same-sex marriage became legal in Indiana, Oklahoma, Utah, Virginia and Wisconsin, where the authorities had been appealing defeats against local bans on same-sex marriage in the lower courts.

Legal experts said gay marriage was also now “presumptively legal” in six further states that shared jurisdictions with the appeal court circuits that heard the defeated appeals: Colorado, Kansas, North Carolina, South Carolina, West Virginia and Wyoming.

In four out of the five states involved in the appeals, the top law officers were Republican. In Wisconsin, the attorney general, JB Van Hollen, acknowledged through a spokesman that the fight to preserve the state’s constitutional ban on same-sex marriage was lost despite “every effort” deployed by his office. In Indiana, attorney general Greg Zoeller, said the legal process had been the state’s “duty” to conduct, but was now over.

David Prater, the district attorney of Oklahoma County, the state’s largest, advised the county clerk’s office to begin issuing same-sex marriage licenses shortly before noon on Monday. “I swore on the constitution to uphold the law and the courts,” Prater told the Guardian in a telephone interview Monday. “And I stand by that oath, no matter what they decide.”

Mary Fallin, the Republican governor of Oklahoma, issued a sharp condemnation of the decision, calling it a “violation of states’ rights”. She added: “The will of the people has now been overridden by unelected federal justices, accountable to no-one.”

In Utah, another deeply conservative state, governor Gary Herbet expressed “disappointment” in the supreme court decision but conceded defeatl. “Ultimately, we are a nation of laws, and we here in Utah will uphold the law.”

At the Salt Lake county clerk’s office, Gregory Enke, 51, and Ariel Ulloa, 37, picked up a license shortly after noon. Ulloa told The Associated Press he would telephone his parents and come out to them as gay before marrying his partner of eight years at the clerk’s office that afternoon. “It’s very important because we feel like we have finally accomplished something that we have been working for for so long,” Ulloa said. “We feel like justice is being done, in a way.”

Gregory Enke and Ariel Ulloa celebrate after getting married at the Salt Lake county clerk’s office in Salt Lake City. Photograph: Rick Bowmer/AP

Evan Wolfson, president of the campaign group Freedom to Marry, welcomed the supreme court’s decision to allow the lower courts’ rulings to stand. “The court’s letting stand these victories means that gay couples will soon share in the freedom to marry in 30 states, representing 60% of the American people,” he said in a statement.



But he called on the justices to “finish the job”. He said: “We are one country, with one constitution, and the court’s delay in affirming the freedom to marry nationwide prolongs the patchwork of state-to-state discrimination and the harms and indignity that the denial of marriage still inflicts on too many couples in too many places.”



Opponents of same-sex marriage were furious at the decision. Brian S Brown, president of the National Organization for Marriage, said the group was “surprised and extremely disappointed”, and added in a statement: “This is wrong on so many levels.” He said it was “mind-boggling” that lower-court judges would be allowed to “redefine” marriage “and our highest court would have nothing to say about it”.

Ed Whelan, of the Ethics and Public Policy Center, an opponent of same-sex marriage, criticised the court for its “irresponsible” decision. He conceded that it would be hard for the court to rule against same-sex marriage in future, having allowed so many pro-marriage rulings to stand.



The decision was clear in its implications for the five states directly covered by the appeals turned away by the supreme court. Same-sex marriage became legal when the appeal courts dissolved the stays they had been put in place when ruling in favour of same-sex marriage.

“The only point of the stay order was to maintain the status quo pending the ultimate resolution of the cases, and there is now an ultimate resolution of the cases,” said William Eskridge, a professor at Yale Law School.

There are still hurdles in the path to legalising same-sex marriage in the six other states where appeal-court rulings also applied. District courts may decide that cases before them were different enough to warrant new appeals. “This is an area of the law in flux though and it is not inconceivable that a district court in one state might decide to argue its case is different enough from another in the same circuit to warrant a fresh appeal,” said Jessica Levinson, a supreme court commentator and professor of law at Loyola Law School in California.



States could also petition the courts for rulings en banc - that is, in a sitting of all the judges on the court. But the lower courts would nevertheless be bound by the precedent set by the appeals that the supreme court allowed to stand on Monday.

In Wyoming, one of the states affected in a knock-on fashion by the ruling, governor Matt Mead said the attorney general would continue to defend its marriage ban. A hearing on a pending case there is scheduled for 15 December.

The supreme court move took legal experts by surprise, as the prevailing expectation was that the justices would simply delay making a decision, rather than turn the appeals away. “The impacts are pretty substantial and that may just may be an indicator that if and when they do [rule], they may well rule in favour of marriage equality in any event,” said Carl Tobias, Williams professor of law at University of Richmond.



One of the supreme court justices, Ruth Bader Ginsburg, suggested in September that the court would delay taking up a case until a circuit court delivered ruling against same-sex marriage, which may happen in one of the more conservative circuits.