Jon Tevlin
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Some time this week, there's a good chance that Garry Peterson, the retired Hennepin County medical examiner, will go to South Dakota to complete a case that has bookended his career, confounded law enforcement, divided a social movement that began in Minnesota and symbolized a political era.

Peterson ran the examiner's office from 1984 to 2004, but worked there as an assistant since 1973. It was in 1976 that one of the most mystifying and politically loaded cases dropped in his lap.

Anna Mae Pictou Aquash was an Indian activist who took part in the occupation of Wounded Knee in 1973. She moved to Minnesota in 1974 and worked for the Red School House in St. Paul, and later at the headquarters of the American Indian Movement in Minneapolis.

She became an outspoken advocate of Indian rights and a close associate of AIM leaders such as Dennis Banks, Leonard Peltier and Vernon and Clyde Bellecourt. She participated in other occupations, and in 1975 was indicted for possessing illegal firearms and explosives. Then she disappeared.

On Feb. 24, 1976, a body was found in a ravine at the Pine Ridge Reservation. A local medical examiner quickly attributed the death to natural causes. Her hands were removed and sent to the FBI in Washington, D.C., where they were identified as Aquash's. She was 30.

A few days later, well-known Minnesota civil rights attorney Ken Tilsen got a call. The Aquash family suspected foul play and wanted an investigation. Others were also demanding answers.

"I contacted Dr. Peterson at Hennepin County, and he went to South Dakota at my request," said Tilsen, now retired and living in Hudson. "We moved very quickly. She died of a bullet wound in the back of the head, and it was very visible."

Tilsen recalls the reports of shoddy work from the original examiner. "His autopsy indicated the weight of her organs, but he had never opened her up. [To him] it was just another dead Indian found in the hills," Tilsen said.

Tilsen still believes the FBI knew the body was Aquash from the start because the agent in charge of finding her showed up at the autopsy.

Because Peterson will likely testify in the coming days, he declined to speak about the case in depth.

"It was clearly one of the bigger ones of my career," said Peterson, 68, who gained a national reputation for his work. "I was a very young man then, and I'm an old man now. This will probably be the last time I have to testify in a case."

Two people have been convicted of participating in the murder. A third was acquitted. The trial that started in Rapid City, S.D., on Monday is against John Graham, the alleged shooter, who held out in Canada until being extradited in 2006. He has denied involvement, but the others are expected to testify against him.

Did Peterson ever expect to see an end to his first big case?

"I didn't know," he said. "I heard rumors from time to time, but I didn't know if it would be solved."

One rumor suggested that movement leaders had her killed because she knew too much, or was an FBI informant, something the feds have denied. Some Indians wondered if the FBI was behind it. The murder pitted factions of the movement against each other, and signaled the end of its radical rise.

"It's like an Agatha Christie novel," Peterson told this newspaper more than a decade ago. "It's one of the most interesting cases I've worked on -- a historic case."

A historic case that may finally be closed because a young examiner did his job when others wouldn't, followed the evidence, and found the bullet hole.

jtevlin@startribune.com • 612-673-1702