A federal appeals court is set to consider gay marriage bans in Idaho, Nevada, and Hawaii.
The 9th US Circuit Court of Appeals has scheduled two hours of arguments Monday on whether such bans should be struck down in Idaho and Nevada.
Hawaii legalized gay marriage in December so that appeal may be dismissed.
The appeals court has previously ruled in favor of gay marriage.
Supporters of bans argue that states have an interest in promoting marriage between a man and a woman, which they say is optimal for childrearing.
Opponents of bans counter that there is no data supporting the childrearing contention and they argue that the marriage prohibitions are unconstitutional.
The arguments are the latest at the federal court level where same-sex wedding proponents have gained numerous victories.
A federal appeals court in Chicago on Thursday struck down as unconstitutional same-sex marriage bans in Indiana and Wisconsin, the Monitor's Warren Richey reported.
"The three-judge panel of the Seventh US Circuit Court of Appeals voted unanimously to invalidate the state bans, as well as measures that barred recognition of same-sex marriages performed in other states," Mr. Richey wrote.
In the past year, more than 20 federal judges have ruled that specific state bans on gay marriage are unconstitutional. The single exception so far occurred Wednesday when US District Judge Martin Feldmen upheld Louisiana's ban on same-sex marriages.
In that ruling, the judge criticized the "volley of nationally orchestrated court rulings” by judges who “appear to have assumed the mantle of a legislative body,” Mr. Richey reported on Wednesday.
Judge Feldman said that other judges were misreading the US Supreme Court’s decision last year in US v. Windsor, a ruling that struck down a portion of the federal Defense of Marriage Act.