Kenney said the tribe was in no way trying to pick a fight with the federal government, which partially funds some aspects of Coquille life, including education, natural resources and some health care.
"This is a very internal matter," he said.
In the Brantings' case, the couple -- who are in the process of moving out of Oregon and back to their native Edmonds, Wash. -- would receive tribal health-care benefits under a plan that is 100 percent funded by the tribe, Kenney said.
Sarah Deer, a tribal law attorney, said she doesn't see any reason why the federal government would or should intervene in the Coquille's marriage law, because the legislation does not involve any expenditure of federal funds.
Still, she said, "that's not to say they won't try."
Nedra Darling, spokeswoman for the federal Bureau of Indian Affairs, said the government had no reason to interfere.
"The tribes can dow this basically, because the tribes have the ability to regulate domestic relationships," she said.
The Coquille tribe, which is based in southwest Oregon and has about 860 members, received federal recognition in 1989.
Tanner said that there have been some tribe members who are displeased by the new legislation and that he appreciates their views just as he does the opinions of the law's supporters.
"Many people have expressed pride in the tribe's courage" to legalize same-sex marriage, Tanner said.
"We only ask that people respect differences and all the Creator's creations," he said.
Deer, who is a visiting professor at the William Mitchell College of Law in St. Paul, Minn., and a victim advocacy legal specialist for the California-based Tribal Law and Policy Institute, said she also does not know of any other American Indian tribe that has sanctioned or legalized same-sex marriage, but that doesn't mean they don't exist.
"Very few of them want to make a splash in mainstream culture," she said.
Some tribes, however, have signed documents banning gay marriage, including the Oklahoma-based Cherokee Nation and the Navajo Nation, in Arizona, New Mexico and Utah.
Many other tribes, Deer said, have marriage laws that are modeled after state and federal legislation, not necessarily because of the tribe's belief system, but because such tribal laws are typically drafted for the tribe by outside legal counsel.
Still, she said, it's not uncommon for tribes to issue their own marriage licenses or perform traditional wedding rituals.
"Any time a tribe asserts its own definition of a cultural norm ? it's better they do it on their own terms," Deer said.
Kitzen Branting, then Kitzen Doyle, was a freshman in high school when she met Jeni Branting. The girls' announcement of their sexual orientation was "bumpy," Kitzen Branting said.
The two are now considered permanent members of each others' families.
"We've definitely had our ups and downs over the years," she said. "But overall they've been very supportive."
The women have lived on the tribal reservation in Coos Bay, Ore., for about a year but they are moving back to Washington to live with Jeni Branting's grandmother who was widowed in January.
Nevertheless, Kitzen Branting said she will remain as involved with her tribe as she ever was. She is a Coquille descendent on her father's side, while her mother is Irish. The engagement ring she wears is a traditional Irish claddagh, while Jeni Branting sports a diamond.