New Mexico medical investigators have not performed an autopsy for the Navajo Nation in more than a year because of unpaid bills for their services totaling a quarter-million dollars.

That means prosecutors and public health agencies on the nation's largest Indian reservation are forced to handle many cases without them. Navajo prosecutor Leonard Livingston said he has about 10 cases pending involving deaths with no autopsies; he's reviewing to see what can be done with them.

The Navajo Nation owes $254,000 to the New Mexico Office of the Medical Investigator — which stopped doing business with the tribe in April 2006 because of the tab, said OMI associate director Tim Stepetic.

"We saw no other course than to place a moratorium on Navajo Nation autopsies," he said.

The FBI handles the tribe's most extreme homicide cases, including the autopsies.

But the Navajo Nation investigates other death cases, which can include those that are drug-related, accidental or suicides.

Some Navajo criminal investigators are trained to determine the cause of death. Others sometimes have to make the best guess, which doesn't hold up in court, Livingston said.

Judges and juries "want docs to make the determination," he said.

Livingston said the inability to get an autopsy done has been most problematic when families have had questions about how their loved ones died. "I didn't have an answer for them," he said.

If investigators come across a body in the field, and they don't believe the death is suspicious, the body is turned over to the family, said Douglas Joe, a criminal investigations supervisor for the Shiprock district.

But without an autopsy, "we would never know" whether criminal charges could have been pursued, Joe said.

Even if homicide cases generally are being covered, Stepetic said there certainly are some that are being missed. The problem also makes it difficult for the tribe's public health agencies to come up with reliable statistics.

For example, it is difficult for the tribe to know whether methamphetamine-related deaths are rising or falling without autopsy information, Stepetic said.

"They don't have a picture of why people are dying on the reservation," he said.

The tribe's bill peaked at $300,000 in April 2006. Stepetic said his office received some payments last summer but no other payments have been made since July.

A measure in the Navajo Nation Council that would have appropriated more than $275,000 for outstanding autopsy services failed twice last year. Once, it was tabled; the measure died in a subsequent session died because the sponsor didn't show up.

Officials for the tribe — the nation's largest, spanning over parts of New Mexico, Arizona and Utah — now are counting on the council's summer session this July to release the money.

"Not to blame the council, but we are at the mercy of the council," said Samson Cowboy, director of public safety for the tribe.

The $254,000 has been written off by the University of New Mexico, which administers state funding to the state medical examiner, but Stepetic said that doesn't excuse the tribe's bill.

He has offered to meet with the appropriate tribal officials to set up a payment plan, but he said he hasn't heard back.

"It's kind of frustrating, but I think the money matter is second to the general requirements for a good death investigation system on the Navajo Nation," he said.