Police investigators carefully documented and collected the bones and gave them to the state medical examiner, who determined they were too old to raise suspicion of a crime. The medical examiner then turned them over to the Utah Department of Heritage and Arts' cultural anthropologist to determine their age and heritage.
"They could be [from] an unmarked pioneer gravesite or Native American," said Geoffrey Fattah, spokesman for UDHA, on Friday. "To the untrained eye [the bones] could be 200 years old to 2,000 years old. We're in the process of investigating that, and it may take a while."
Not only does analysis take time, there's a growing queue of other remains to get through first. The discovery of old bones is more common than people think, Fattah said. The UDHA receives human remains about twice a month, usually after someone was digging for a water main or power lines.
The Fremont Indians, in particular, buried their dead wherever they died, not in communal graveyards, so people find their remains everywhere from farm yards to backyards in the Avenues, Fattah said.
If the bones belong to an existing Native American tribe, they will be handed over to the tribal leaders. Otherwise, the state has a dedicated spot for unclaimed native remains.
"Several times a year we ask members of Native American tribes to offer a blessing, [saying] we're sorry we disturbed you, may you rest in peace," Fattah said.
If the bones aren't Native American, they will be turned over to the county where they were found, and the county arranges for a publicly funded interment.
The Salt Lake City Police Department and the UDHA stressed that the homeowner did the right thing by immediately calling the police. The placement of the bones can offer clues as to their heritage.
Neither agency could speak to whether anything else, such as pottery or other artifacts, were found with the remains.
It's possible the remains were moved from their original spot to another, Fattah said. But police are waiting on the cultural anthropologists's conclusions before investigating the remains as anything criminal, including grave robbery, said Detective Dennis McGowan.