BOISE - A federal judge says she will decide soon if Idaho's ban on same-sex marriage violates the equal protection guarantees of the U.S. Constitution.

U.S. Magistrate Judge Candy W. Dale told attorneys for four couples Monday that the emotional case raised lots of questions, and that she would get a ruling out in the "relatively near future." She declined to give a specific date, and it wasn't clear if her decision would come before other cases pending across the nation.

The four couples, all women, say Idaho discriminates by subjecting them to different tax rules and denying them rights given heterosexual families. Their attorney, Deborah Ferguson of Boise, said the sole purpose of Idaho's 2006 constitutional amendment banning same-sex marriage is to subject same-sex couples to stigma and shame.

"Ten out of 10 federal district courts which have considered challenges to their states' same-sex marriage bans have found them to be unconstitutional, and likewise we are here to ask this court to do the same," Ferguson said.

Gov. Butch Otter, a defendant, says states have the right to define marriage as they see fit. He contends that the same-sex marriage ban is vital to Idaho's goal of creating "stable, husband-wife unions for the benefit of their children."

The Idaho couples filed their lawsuit in November against the governor and Ada County Clerk Chris Rich. The couples are Sue Latta and Traci Ehlers; Lori and Sharene Watsen; Shelia Robertson and Andrea Altmayer; and Amber Beierle and Rachael Robertson.

Latta and Ehlers married in 2008 in California, and the Watsens married in 2011 in New York. Both couples have children and say Idaho wrongly treats Ehlers as a legal stranger to her grandchildren and requires Lori Watsen to obtain a new power of attorney every six months so she can have legal authority to consent to medical treatment for her son.

The case comes down to a matter of states' choice and states' authority, said Thomas Perry, the attorney for Gov. Butch Otter.

The law influences people's behavior "through powerful social norms," Perry said, and without it, the state would endure the erosion of what he called a child-centric culture of marriage.

"We believe that there are significant risks imposed in redefining marriage in genderless terms," Perry said.

Idaho Deputy Attorney General Scott Zanzig, representing Rich and the state, said the lawsuit is premature because the Supreme Court hasn't said that individuals enjoy a fundamental right to same-sex marriage.

He said Idaho's constitutional amendment wasn't a change, but rather reinforced the approach the state has always had.

"The plaintiffs argue that Idaho's marriage laws are the result of animus and discrimination," Zanzig said. "That's simply not true ... Idaho's laws have always said that a marriage is between a man and a woman."

Tradition doesn't protect Idaho from scrutiny when it has unconstitutional laws, countered Ferguson.

"Traditional discrimination is just another way of saying discrimination that has happened for a long, long time," Ferguson said.