Mark Hacking (search) was charged with first-degree murder Monday after he allegedly told his brothers that he shot his wife Lori in the head and threw the body in a garbage bin.

The body of Lori Hacking (search) still hasn't been found, but searchers continue to scour a local landfill.

Mark Hacking told his brothers that early on the morning of July 19, he walked into the bedroom he shared with his wife and fired a single shot into her head with a .22-caliber rifle while she slept, according to a probable-cause statement released Monday.

He wrapped her body in garbage bags and put the body in a trash bin at around 2 a.m., then disposed of the gun in another bin, the statement said.

The murder charge carries a possible sentence of five years to life in prison. Hacking was also charged with three counts of obstructing justice; each carries a possible one to 15 years in prison.

Salt Lake County District Attorney David Yocom (search) had the option of filing a count of aggravated murder against Hacking, which carries the death penalty, but the absence of Lori Hacking's body would have made that difficult to prove.

Yocom did not file a homicide charge to account for the death of Lori Hacking's unborn baby.

Gil Athay (search), Mark Hacking's attorney, did not immediately return a message seeking comment. Athay has drawn attention to the circumstances of the alleged confession.

"Remember Mark was housed in a psychiatric unit for the period of time these brothers are claiming they spoke with him," Athay told Salt Lake television station KUTV last week. "To me that creates a substantial issue."

Mark Hacking is scheduled to make his first court appearance Tuesday.

An unidentified tipster gave police information that led to the landfill search, which was expected to resume this week.

Just before she vanished, Lori Hacking, 27, told friends she was five weeks pregnant, relying on a home pregnancy test. Because her body remains missing, police have not been able to determine if she was pregnant. She apparently did not see a doctor.

Even without Lori Hacking's body, police have said they're confident in the case against her husband.

Mark Hacking, 28, reported his wife missing July 19. He said she had gone jogging at a downtown park but never made it to work.

But it wasn't long before police determined that the husband had a history of deceit. They said his wife probably never went for a run that morning.

The night of July 19, police found Mark Hacking nude outside a hotel near the couple's apartment. His family checked him into a psychiatric ward, where he stayed for more than a week before police arrested him.

His two older brothers, Scott and Lance, talked with him at the hospital July 24 and later told police that he confessed to killing his wife as she slept.

Since the day his wife was reported missing, Mark Hacking's credibility has eroded amid revelations that he lied to his family about enrolling at medical school in North Carolina and about graduating from the University of Utah.

Despite the lies, police believe the statements attributed to Hacking in the probable cause document are credible. "Everything corroborates the truth of this statement," Yocom said.

The Friday before she was reported missing, Lori Hacking left work stunned and sobbing. Her co-workers said she had been making some arrangements with the medical school, and that they believe an administrator was calling back to say Mark Hacking wasn't enrolled there.

His father believes Mark Hacking "just snapped" and killed his wife after she learned his lies about his education and career plans had been going on for years.

Hacking was arrested Aug. 2. An affidavit filed by police says investigators found human blood on a knife in the couple's bedroom and on the headboard and bed rail. The blood also matched traces of blood found in Lori Hacking's car, police allege.

The Associated Press contributed to this report.