Plaintiffs in the case challenging Utah's same-sex marriage ban before the 10th Circuit Court of Appeals in Denver. 

(Photo: CPR/Megan Verlee
The debate over gay marriage was front and center in Denver on Thursday when the 10th Circuit Court of Appeals heard arguments over Utah’s law banning same-sex marriage. 

This is the first of a slew of gay marriage cases to make it to the federal appeals process since the Supreme Court struck down much of the federal Defense of Marriage Act last year. 

And both sides looked to just that ruling, known as United States v. Windsor, to make their case.

The judges are weighing two conflicting interests – the authority of states to set their own marriage laws versus how much protection the U.S. Constitution gives gays and lesbians to marry. 

Utah Attorney General Sean Reyes says language in the Windsor ruling shows the justices are following a federalist interpretation.

"This case, fundamentally, is about the right of a state like Utah to determine something as significant and fundamental as marriage through the democratic process," Reyes told reporters outside the court.

But on the other side, Peggy Tomsic, lead lawyer for the plaintiffs, worked to convince the appeals court panel that Windsor actually enshrines marriage as a fundamental right, protected under the 14th amendment from unfair state interference.

For their part, the three judges seemed split over in their views of the case.

At one point, Judge Carlos Lucero, who appeared most sympathic to the plaintiffs, asked Tomsic rhetorically, "Has public policy ever been allowed to overrule fundamental rights in this country?" Tomsic enthusiastically answered no. 

But Judge Paul Kelly took a harder line, pushing Tomsic to explain how granting a right to same sex couples to marry wouldn't also require the court to extend that right to people with multiple partners. "It seems to me it all goes together," Kelly said.

The swing vote on the panel may come from Judge Jerome Holmes, a relatively recent appointee. Holmes made it clear that his decision rests on the question of how much scrutiny courts should impose on laws that disadvantage gays and lesbians, something past Supreme Court rulings have left murky.

After the arguments, lead plaintiff Derek Kitchen said the day was thrilling, but difficult.

"It’s hard to hear people argue against us because we are loving and committed individuals who have committed emotionally, spiritually to our partners," Kitchen told reporters.

A federal district court judge struck down Utah’s ban last December, but the state appealed that ruling. 

With several circuit courts poised to hear arguments over state marriage laws in the coming months, it looks increasingly likely that the U.S. Supreme Court will have to take up the issue in its next session, which starts this fall. A challenge to Colorado's amendment is currently pending in state court.

The 10th Circuit will hear a challenge to Oklahoma’s marriage law next week.