Washington (CNN) -- House Republicans have signaled they plan to ask the Supreme Court by month's end to get involved in a constitutional fight over same-sex marriage.
In a federal court filing Wednesday in Connecticut, the House of Representatives' Bipartisan Legal Advisory Group asked a judge to put on hold consideration of a pending lawsuit in that state over the Defense of Marriage Act (DOMA).
The 1996 congressional law defines marriage for federal purposes as exclusively between a man and a woman.
A separate federal appeals court based in Boston last month struck as unconstitutional a key part of DOMA, ruling the federal government cannot deny tax, health and pension benefits to same-sex couples in states where they can legally marry. That ruling is a boost for gay rights advocates and the Obama administration, which in a rare move, has refused to defend a federal law in court.
Lawyers for House Republicans, who have now picked up defense of DOMA, said pending court challenges in other jurisdictions should now be put on hold until the justices ultimately decide whether to take up the separate case from Massachusetts.
The first step would be for congressional leaders to formally ask the justices to intervene, by filing a so-called "petition for certiorari."
In their motion this week in the current Connecticut dispute, GOP leaders said they would do that "by the end of the month," predicting it would be a "good candidate for Supreme Court review."
The 1st U.S. Circuit Court of Appeals, based in Boston, did not rule on the federal law's other key provision: states that do not allow same-sex marriages cannot be forced to recognize such unions performed in other states. Traditionally, marriages in one jurisdiction are considered valid across the country.
DOMA was enacted in 1996, when Hawaii was considering legalizing same-sex marriage.
Marriage between two males or two females is legal in the District of Columbia and six states -- Massachusetts, Connecticut, Iowa, Vermont, New Hampshire, New York, and Washington state. It set to be legal in Maryland next January, but implementation could be delayed by opponents placing the question on the November ballot.
Many other states, including New Jersey, Illinois, Delaware, Rhode Island and Hawaii, have legalized domestic partnerships and civil unions for such couples -- a step designed in most cases to provide the same rights of marriage under state law.
But other states have passed laws or state constitutional amendments banning such marriages.
The 1st Circuit appeals court said it recognized how divisive the issue is, and noted it may ultimately be up to the Supreme Court to decide. But this decision is the first at this judicial stage to find the heart of the law unconstitutional.
"Many Americans believe that marriage is the union of a man and a woman, and most Americans live in states where that is the law today," said Judge Michael Boudin, appointed to the bench in 1992 by President George H.W. Bush. "One virtue of federalism is that it permits this diversity of governance based on local choice, but this applies as well to the states that have chosen to legalize same-sex marriage. Under current Supreme Court authority, Congress' denial of federal benefits to same-sex couples lawfully married in Massachusetts has not been adequately supported by any permissible federal interest."
It is in effect only within states with gay marriage laws covered by the 1st Circuit -- Massachusetts and New Hampshire -- and has limited enforcement. That means there will be no immediate eligibility for financial benefits currently denied same-sex married couples. No change is likely until the high court decides the matter.
The separate Connecticut challenge was brought by same-sex couples there and in Vermont and New Hampshire, who are all legally married.
They challenge DOMA on equal protection laws. Lawyers for those plaintiffs indicated they would oppose the House leaders' motion to stay the case until and if the high court decides whether to take up similar challenges.
The high court begins its summer recess late next week, and the justices would not likely make a decision on accepting the appeals until early October at the earliest. Oral arguments would not likely be held until early next year.
DOMA is being officially defended in court by House Republicans, led by Speaker John Boehner, R-Ohio, who stepped in after the Justice Department refused to participate. The Obama administration announced last year it believed the law to be unconstitutional.
A bill known as the Respect for Marriage Act is working its way through Congress and would repeal DOMA.
The larger issue has been working along two legal tracks. A federal appeals court last month ruled against California's voter-approved ban on same-sex marriage, arguing the ban unconstitutionally singles out gays and lesbians for discrimination.
In a split decision, a three-judge panel of the 9th U.S. Circuit Court of Appeals found the state's Proposition 8 "works a meaningful harm to gays and lesbians" by denying their right to civil marriage in violation of the 14th Amendment.
These latest developments signal the first high court debate over same-sex marriage could be over federal, not state laws.
The justices would have ultimate discretion to accept one, both, or neither case -- perhaps deferring judicial review until a later time, after other lower courts have had time to debate the matter.
The Connecticut case is Pedersen v. Office of Personnel Management (10-cv-1750).