Oglala Sioux tribal officials want federal authorities to reopen investigations into 16 more unresolved deaths and disappearances at a South Dakota reservation, including one dating back nearly 50 years, a lawyer for the tribe said Wednesday.

Tribal officials presented the list of names to U.S. Attorney Brendan Johnson during a meeting in Rapid City. The list adds to the 28 deaths on or around the Pine Ridge Indian Reservation that Johnson agreed to re-examine nearly a month ago.

Lawyer Jennifer Baker gave the latest list to The Associated Press before the daylong meeting of the tribe's law and order committee.

As with the first list — submitted in May — the majority of cases presented Wednesday are from the 1970s, when the murder rate on the reservation was the highest in the nation and tension between the American Indian Movement and federal authorities was high.

But the new list broadens the scope of the requested investigations by several decades by including the 1964 death of Delbert T. Yellow Wolf, the oldest case presented for re-examination so far, and the 2010 death of Samantha One Horn. One person on the list is missing but has not been declared dead.

Baker — of the Colorado firm Smith, Shelton, Ragona & Salazar, which is working with the tribe — said tribal leaders expanded the original list after uncovering new information. Further details on the cases were not made available.

Johnson said his office will cross-reference the names from the lists. Three attorneys from his office already are going through files and seeing if there are cases in which new prosecutions could be brought or additional investigative work is necessary.

Johnson said prosecutions on the Pine Ridge reservation increased last year, and that active cases will continue to take precedent over inactive cases. Some of the old cases could be reviewed in as little as six to 12 months, he said, while others "could take a long time."

The original list contained 28 cases that Oglala Sioux officials wanted reopened because they said the FBI hadn't sufficiently investigated them. Eleven more cases resulted in prosecutions, but the tribe believed those prosecuted "were inadequately charged and/or received insufficient sentences."

Baker acknowledged further prosecution was unlikely because the American judicial system doesn't allow for suspects to be tried twice for the same crime.

Last month, Johnson announced three attorneys from his office would review the case files from the first list of names. But because many of the cases occurred during a violent period of the 1970s, Johnson said it would likely be challenging to gather new evidence.

The FBI typically investigates murders on reservations while the U.S. Attorney prosecutes the cases.

Tom Poor Bear, the tribe's vice president, said the requests for new investigations stem from tribe members' "lack of trust in the FBI."

"I would like to see a special team of investigators other than the FBI come down and investigate these deaths," he told the AP in June. He didn't return a phone call seeking comment Wednesday.

The original list includes the deaths of Poor Bear's brother, Wilson Black Elk, and cousin, Ron Hard Heart, whose bodies were found in 1999 on reservation land across the border from Whiteclay, Neb.

One reopened case has been successfully prosecuted.

American Indian Movement activist Annie Mae Aquash's 1975 killing went unsolved for decades until Fritz Arlo Looking Cloud was convicted of first-degree murder in 2004 in federal court. John Graham was convicted in state court for the death in 2010.

The FBI in 2000 issued a report detailing their investigations into the deaths of 57 people that occurred during the 1970s. The report said the bureau was right in closing the cases, even in situations where no one had been prosecuted for a death deemed unnatural.


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