A Missouri woman will spend the rest of her life in prison after admitting that prosecutors had evidence to convict her of killing a mentally disabled man in what authorities believe was part of a complicated plot to divert attention from another homicide case.

Pamela Hupp, 60, of O'Fallon, entered an Alford plea Wednesday that calls for life in prison without the possibility of parole at sentencing in August. Hupp could have faced the death penalty if convicted of first-degree murder in the August 2016 death of 33-year-old Louis Gumpenberger.

St. Charles County prosecutor Tim Lohmar said after the hearing that the evidence was overwhelming and he believes Hupp "deserves to be put to death." But he cited several factors in the plea deal, including the fact that the victim's family preferred that she spend life in prison. He also cited the expected $300,000 cost of a trial.

St. Charles County authorities believe Hupp killed Gumpenberger to distract from the re-investigation of the stabbing death of Betsy Faria in 2011 in neighboring Lincoln County.

Russ Faria was convicted of killing his wife in 2013, but the conviction was overturned and he was acquitted in a 2015 retrial. Russ Faria blamed Hupp, saying she had a motive after becoming the beneficiary of a $150,000 life insurance policy shortly before Betsy Faria was killed.

Lincoln County prosecutor Michael Wood told The Associated Press that he wants to re-examine the Faria investigation now that Hupp's case is resolved in St. Charles County.

Wood said he hasn't determined if Hupp is a suspect in Betsy Faria's death, but "people in the community believe she's the leading suspect."

A phone message left with Hupp's attorney was not returned.

Gumpenberger, who was mentally and physically impaired from a 2005 car wreck, was killed on Aug. 16, 2016, the victim of a bizarre plot staged by Hupp to make it look like she was a kidnapping victim acting in self-defense, police said.

Hupp originally told police that she got out of her car on her driveway and Gumpenberger, whom she described as a stranger, pulled a knife and demanded she take him to a bank "to get Russ's money," an apparent reference to the insurance money she collected from Betsy Faria's death.

Hupp told authorities she knocked the knife out of Gumpenberger's hand and ran into her house on a quiet, middle class street. She said she got a gun and fatally shot Gumpenberger, who had followed her inside.

The story quickly unraveled. Lohmar said that days before the killing, a woman reported that someone matching Hupp's description in an SUV approached her claiming to be a producer for the TV show "Dateline" and promised to pay $1,000 if she would record a scripted sound bite about 911 calls. The woman at first agreed but backed out when the woman failed to show any credentials.

Lohmar said a surveillance camera showed the SUV's license plate, which matched Hupp's. He has said authorities believed Hupp was "vetting a potential victim."

Data from Hupp's cellphone indicated that Gumpenberger was not a stranger as Hupp had claimed — GPS showed she was at his apartment, 13 miles (20.92 kilometers) from her home, less than an hour before the fatal confrontation.

Police found $900 in plastic bags in Gumpenberger's pocket after his death, and a note that appeared to be instructions to kidnap Hupp and collect Faria's money. Authorities said the money and note were planted.

Lohmar said that after Hupp was arrested in Gumpenberger's death she stabbed herself with a ball point pen multiple times in the neck and arms in the O'Fallon police station, requiring hospitalization.