OKLAHOMA CITY — Darren Black Bear hasn't thought too much about his upcoming nuptials. Maybe khaki pants, and he doesn't mind if guests show up in Halloween costumes even though the wedding will be a rare sight: He and his partner are getting legally married in Oklahoma even though the state bans same-sex marriage.

How? His bloodline.

Black Bear and his partner of nine years, Jason Pickel, plan to walk each other down the aisle Thursday, surrounded by family and friends, before signing a marriage license granted by the Cheyenne Arapaho Tribes. Black Bear, 45, is a member of the Oklahoma-based tribe, which is among the few Native American tribes in the U.S. that allow same-sex marriage.

Like all federally recognized tribes, the Cheyenne Arapaho can approve laws for its land and members. Its code regarding marriage doesn't address gender, referring to the parties simply as "Indians," and requires that one person be a member of the tribe and reside within its jurisdiction.

It was on a whim, sparked in part by the U.S. Supreme Court's decision earlier this year to grant federal benefits to same-sex couples, that Pickel, 36, called the tribe to see if they could marry under tribal law instead of getting married in Iowa or another state where gay marriage was legal.

"Surprisingly enough, they told him that yes, they had already married one couple, and that it's $20 to get married," Black Bear said.

"I'm just really happy we are able to finally get married," Pickel added later at the couple's home in Oklahoma City. "And one day, when we have true equality in all 50 states, we will hopefully have all the same benefits and rights in every state."

At least six other tribes allow same-sex marriage, including the Coquille Tribe in Oregon and the Little Traverse Bay Bands of Odawa Indians in Michigan, states that also ban same-sex marriage, according to national gay marriage advocacy group Freedom to Marry. Other tribes, such as the Cherokee Nation, specifically bar gay marriage.

The U.S. Bureau of Indian Affairs said it doesn't track how many of the nation's hundreds of recognized tribes allow same-sex marriage.

Like gay couples who legally marry in other states, Black Bear and Pickel won't be awarded state benefits given to married couples in Oklahoma. But they will receive federal marriage benefits, and they said a primary reason they decided to marry was to enable Pickel to be added to Black Bear's health insurance.

Still, both men said they wanted to show their commitment to each other, and to encourage other tribes and states to adopt similar laws. The couple decided to become more outspoken after they were refused a room at an extended-stay hotel in another state because of their relationship, which resulted in Pickel — long the more vocal of the pair — convincing a local television station to report on the controversy.

"We've already seen the best and the worst in each other. We've already experienced all that. We just want the same benefits and we just want to be treated the same," Black Bear said, noting that he was grateful for the tribal law.

"He does keep me centered. I tend to dream big," Pickel added. "I've always been an advocate for equal rights so I guess it's kind of natural that it (the wedding) would be public. I just thought it would be somewhere else — I thought it would be in a different time and a different place before we'd even have this be able to occur."

Black Bear's father, a former tribal council member, said he told his son he would be honored to officiate the wedding in Watonga, a town within the tribe's jurisdictional boundaries.

"I'm not like a lot of ministers, judgmental. I have an open mind. I believe that God loves us regardless and he's given us his love so we have to share that," Floyd Black Bear said.

The pair, who met at a Christmas party in Alabama and moved to Oklahoma about five years ago, are among three same-sex couples who have applied for tribal marriage licenses since 2012, Cheyenne Arapaho Tribes spokeswoman Lisa Liebl said. One couple has already married, while the other recently filed for paperwork.

Black Bear hopes other tribes follow suit.

"The fact that the Cheyenne Arapaho Tribes here in Oklahoma are progressive enough to follow federal guidelines, I'm pretty sure that they'll (other tribes) start issuing marriage licenses within their tribes. I'm hopeful they will," he said.

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