The remains of Lori Hacking (search), the young woman allegedly killed by her husband, were so broken up by the time police recovered them from a landfill that authorities may never know how she died.

Autopsy findings released Wednesday confirmed Hacking's identity from dental records, but said experts couldn't determine the cause of death.

Her husband, Mark Hacking (search), who reported his wife's disappearance and asked for volunteers to search for her, was jailed on a murder charge after allegedly confiding to his brothers that he shot her while she slept and threw her body in a trash bin.

The remains were in so many pieces the medical examiner couldn't find a bullet hole, Deputy District Attorney Bob Stott said Wednesday. Nor was there any way to determine if Lori Hacking was five weeks pregnant, as she told friends, he said.

Authorities believe Lori Hacking, a 27-year-old stockbroker's assistant, was killed July 19 after learning her husband wasn't enrolled in medical school in North Carolina, the reason he had given for moving there. It was among a series of deceptions he had perpetuated over several years, police say.

The uncertain autopsy will not affect how Mark Hacking, a 28-year-old hospital orderly, is prosecuted for murder, Stott said Wednesday.

"Finding the body was what helped us, and making the identification," he said.

Police found Lori Hacking's body in a landfill Oct. 1 after picking for weeks through compacted trash 20 feet deep over an area the size of a football field.

Mark Hacking's brothers say that while he was hospitalized in a psychiatric unit he admitting shooting his wife in the head with a .22-caliber firearm, then disposing of her body, the weapon and a bloody mattress in separate trash bins.

The murder weapon and mattress have not been found.

Hacking's next court date is Oct. 29. His bail is set at $1 million.

Because the alleged confession came in the psychiatric ward where Hacking was treated for 13 days after his wife disappeared, his attorney has suggested he might try an insanity defense.