COMMERCE CITY, Colo. -- On Wyoming's Wind River Indian Reservation, Winslow Friday is preparing to surrender in his long fight with the federal government.

The seeds of the conflict were planted four years ago when Friday shot a bald eagle from a tree. His cousin needed a tail fan for an upcoming Sun Dance, the Northern Arapaho Tribe's most important religious ceremony, and Friday wanted to help.

So when Friday spotted the bird, he seized his chance.

Charged with killing an eagle in violation of federal law, Friday had argued that the law hinders the practice of his religion -- a battle closely watched on the reservation.

"Some agreed with what he did, some didn't," tribal spokesman Donovan Antelope said. "But they all agree with the reason he did it -- for the Sun Dance. We know he wasn't doing it just to kill an eagle."

Now, though, Friday is giving up. Having exhausted his legal options, he's hoping for a plea agreement that will avoid a trial.

"The attorneys say that (a trial) would be a losing battle," said Friday, 25, a former oil field worker studying to be a civil engineer.

Friday's case represents the latest and most high-profile fight in a string of battles over how to balance conservation with religious liberty.

A federal official summed up the dilemma.

"You have a precious commodity. It's precious to Native Americans, but it's also precious to the American people. How do you balance that? We're trying our best," said Bernadette Atencio, who supervises the federal Eagle Repository in Commerce City, which collects dead eagles and provides them to Indians for religious use.

Once endangered, the bald eagle has rebounded in recent decades but remains -- along with the golden eagle -- under the protection of the federal Eagle Protection Act.

The law provides an exception for American Indians who want eagles for ceremonies: They can acquire birds from the repository or may apply for a permit to "take," or kill, an eagle.

But many tribes eschew both options, saying the former can take years and yield unsuitable specimens. The latter, they say, is a process so obscure that even some federal officers have been unaware of it.

In Wyoming, Friday didn't pursue either option before he killed the eagle, which carries a maximum penalty of one year in jail and a $100,000 fine. He argued that a repository bird was unacceptable and that his tribe didn't even know a permit system existed.

In 2006, a federal judge sided with Friday, dismissing the case. Prosecutors appealed to the 10th Circuit Court of Appeals, maintaining the permitting system was adequate and used regularly by some tribes, such as the Hopi.

Last year, the appellate court ruled in favor of the government and ordered Friday to stand trial. This year, the U.S. Supreme Court declined to hear his appeal, prompting his willingness to negotiate with prosecutors. Federal prosecutors declined to comment on Friday's case.

In cases such as Friday's, the courts generally have held that the U.S. Fish and Wildlife Service's methods -- the repository and permitting system -- do not hamper religious practices, said Sarah Krakoff, a University of Colorado law professor.

That's a source of frustration for many tribes, said Suzan Shown Harjo, president of the Morning Star Institute in Washington, D.C., which advocates for traditional and cultural rights.

"Restrictions are a way of controlling the religions themselves," she said.

Antelope echoed that view: "People are fed with up with the federal government telling them, `This is what you have to do for your religion. This is how we feel you should do it.' "

Federal officials said they've tried to make the permitting process more accessible.

"We recognized we weren't getting the word out very well, and we've made more of an effort," said Eliza Savage, a Fish and Wildlife regulatory analyst.

Yet, the agency doesn't wish to publicize the process too much.

"We're not in the business of trying to generate interest in the taking of wildlife," Savage said.

The agency typically receives two to three applications per year and approves all but those in which the applicants don't meet the criteria, such as not belonging to a federally recognized tribe or acknowledging they don't "need" the bird, Savage said.

Founded in the 1970s, the repository every year receives about 2,000 carcasses of eagles struck by cars, electrocuted or dead of natural causes; it has a waiting list of 6,000 unfilled requests from American Indians, Atencio said. Some orders -- such as for talons or heads -- can be quickly filled, but it can take years for a whole bird in good condition.

"Those are pretty few and far in between," Atencio said.

To Friday, the aesthetics are important because the eagle is a gift. In the Sun Dance, the eagle helps convey prayers to the creator.

"You would want the gift in nice condition," he said. "It needs to be clean, not broken up, ripped up."

'Disregard for the laws'

On Wind River, officials stay busy investigating reports of people shooting at eagles, said Robert St. Clair, director of the Shoshone and Arapaho Tribal Fish and Game Program.

But they're difficult to catch, he said. "By the time we get there, they're long gone." In the past year, he's found three eagles shot. Two survived; one did not.

"Both of its legs were gone," said St. Clair, noting the reservation has its own rules against killing eagles. "It's blatant disregard for the laws."

American Indians are responsible for far fewer eagle deaths than utility companies and other Americans, Harjo said.

"It's in the native interest to have more eagles survive," she said.

Yet, some do search out eagles on their own -- as Friday did -- rather than follow the rules because they are wary about interacting with a government that once banned the Sun Dance, Harjo said.

"A lot don't want to call attention to themselves," he said. "They will do what they will do in order to carry out their religious duties."