Shelly Harmon had confessed to the Prescott murder that took place in 1988. She was long suspected of killing her roommate Pamela Pitts. However, she was not charged for Pitts's death until 30 years later, according to an ABC 15 News report.

Harmon has already been sentenced to 20 years prison time for the death of her ex-boyfriend when she pleaded guilty in March for the fatal incident with Pitts.

Pitts's case went cold after investigators could not establish the evidence. They needed to capture the suspect responsible for the victim's death. In addition, tips on the case did not add up.

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Suspicions on Harmon

Harmon and Pitts had been roommates before the murder took place. Three years after Pitts's death, Harmon was then arrested for murdering her boyfriend, according to an Arizona Central report.

In 1993, the Prescott murder suspect was convicted. She was then sentenced to 20 years. Detectives said that they had their suspicions on Harmon for Pitts's death through the years. However, new evidence only surfaced years after. They did not specify the evidence until court proceedings are held.

As Harmon's sentence for killing her boyfriend nears its end, police started observing Harmon's phone calls, according to an Associated Press report.

Harmon's ex-boyfriend, Raymond F. Clerx, had wanted to end the relationship. Aside from that, he was reportedly going to take their dogs. Harmon then shot him in a burst of anger as he lay on the roof of a car. The suspect then dumped his body in a mineshaft.

Meanwhile, Harmon's story about Pitts's death changed over the years, now claiming that Clerx was her alibi. She also claimed that another roommate strangled Pitts.

Prosecutors claim that the fight between Harmon and Pitts started over money. The victim had reportedly wanted to move out. Pitts had also shared news of Harmon's pregnancy, which angered the suspect.

In a court document, Harmon was said to have driven around Prescott looking for Pitts.

Pitts started to go missing on Sept. 16, 1988.

Harmon also claimed to have known how to conceal a killing, detailing burning a body or dumping it down a mineshaft.

Pitts's Killing

Harmon added that she was upset with Pitts. She said that the victim was late on rent and had overdrawn a joint bank account. Harmon said she "lost it" due to those incidents.

Harmon confessed she had hit Pitts against the ground until she was no longer moving.

Pitts's family, however, does not buy Harmon's recount of the story. Paul Pitts Jr., Pamela's brother, said he did not believe Harmon, adding that it was just her way to get away with a prison sentence.

Meanwhile, Harmon is now back in Nevada and is now 50 years old. One friend, Mary Burgoon, said she had shared a few meals with Harmon and her husband. Burgoon went on to say that she believes Harmon was unjustly jailed and only pleaded guilty to avoid a jail sentence.

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