A retired LAPD officer fatally shot her ex-boyfriend because she believed he killed a cop

Julia Peat waited for her boyfriend to finish cleaning the pool. Then she fired her 9-millimeter Beretta pistol over and over as he stepped through a sliding back door of her western Arizona home last week.

Several hollow-point rounds tore through his body. Mark Corbett fell, but he didn’t die. So, Peat, a retired Los Angeles police officer, finished him off with a final shot to the head as she stood over his bleeding body, according to a police report detailing the killing.

Peat, 60, was a decorated officer during her time with the LAPD. She was known for her caring demeanor and received a prestigious Crystal Angel Award at the True Blue Police Foundation gala in 2008 for her service in South Los Angeles.

Peat told homicide investigators that she became concerned for her safety after having a conversation with a woman with whom the couple was considering having a three-way relationship several months ago.

The woman, who isn’t named in the police report obtained by The Times, reportedly said Corbett confessed to her that he “had killed a cop and has not been arrested for that incident.� The other woman said Corbett threatened to kill her if she told anyone, the report alleged, but Peat said he had never been violent toward her.

Peat told a police detective she understood the officer’s killing happened in California. Investigators have not confirmed the details of Corbett’s past, but court records show he had a prior felony conviction in the state of Washington.

Julia Peat, a retired Los Angeles police officer, was charged with murder after shooting her ex-boyfriend to death in Arizona. She later took her own life in custody.

(Lake Havasu [Ariz.] Police)

Moments after allegedly killing the 69-year-old Corbett on June 22, Peat called Lake Havasu City police to confess to the shooting. She referred to him as her ex-boyfriend and said he was a felon. When officers arrived, she emerged from the house with her hands in the air and a cellphone wedged between her ear and shoulder.

She left the Beretta on the kitchen counter.

Almost from the beginning, Lake Havasu investigators doubted Peat’s claim that the crime was a spontaneous act. Instead, the report says, their investigation uncovered clues that Peat had been planning the killing for at least a day.

Peat told investigators that, after learning of the cop-killing allegation, she told Corbett “she was not in love with him� and began moving his belongings out of the house. She also stopped drinking, moved her guns to a neighbor’s home and told several people that she suspected Corbett knew she’d found out about his past.

The day before the killing, Peat went to local police and asked an officer to run a background check on Corbett. But the officer was unable to provide any information.

So Peat got her guns back and loaded her 9mm with new hollow-point rounds, according to the report. The following day, she met up with Corbett at an RV dealership and lured him to her home shortly after lunch, saying she wanted to give their relationship another chance.

But in reality, she admitted to police, she was waiting for a moment when his “guard was down,� according to the incident report.

Once at her home, she kissed him and asked him to clean the backyard pool, giving her time to retrieve her loaded Beretta and position herself in the kitchen, waiting for him to return. As Corbett walked through the sliding door, she began firing, according to the police report.

She later told investigators that Corbett exclaimed, “Why?� as she shot him.

Officers found 11 shell casings scattered around Corbett, who was wearing a white shirt, blue plaid shorts and white tennis shoes and lying on his left side. Blood was pooled around his head and chest, the police report noted. Gunshot wounds were visible on his right cheek and forearm.

Lake Havasu police Sgt. Michael Terrinoni said Peat told investigators that she was a former LAPD officer and she shot Corbett because she feared for her life. He said she was arrested on suspicion of premeditated murder.

Peat was taken to the Mohave County Jail in Kingman, Ariz., where she was housed in a cell by herself. Jailers found her unresponsive at about 2:30 p.m. Sunday. A piece of clothing was tied around her neck. A Mohave County sheriff’s statement said jailers tried to resuscitate her, but she was pronounced dead at the scene. Sheriff’s officials called her death a suspected suicide.

LAPD officials said Peat retired from the department in 2017, having most recently worked in the agency’s Harbor Division, which included San Pedro, where she had lived.

“The Los Angeles Police Department is aware of an alleged murder at the hands of retired Officer Julia Peat, who separated from the Department in 2017,� Chief Michel Moore said in a statement. “We send our condolences to the victim’s family and retired Officer Peat, who reportedly committed suicide while in custody.�

A Lake Havasu police report said Peat had told an investigator “she used to be addicted to pain pills� for an unspecified ailment that led to her retirement from the LAPD. She also said she had stopped drinking alcohol recently and took a “lot of prescription medications.�

In one police report, Peat’s daughter told an investigator that she last saw her mother about a year ago, when Peat had a “manic episode.� Her daughter also recalled that her mother’s boyfriend had “prison tattoos.� The daughter, who is not identified by police in their report, said she got a call from Peat the week of the shooting, saying she feared for her safety.

Images posted on social media of Peat seated atop a Harley-Davidson next to a heavily bearded man with long white hair are among the few signs of her activities in recent years.

Corbett, a resident of Bullhead City, Ariz., had lived in the area for the past few years. Records show he previously lived in Altadena.

Correctional records show Corbett was sentenced in 1979 to two years and six months behind bars in Walla Walla County, Washington. They show that he also went by another name, Mark Lemon Peck.

According to court documents and other records, a man named Mark Peck — who was born in the same month and year as Corbett — was convicted of murder in Tennessee in 1989. Authorities said Peck shot and killed a man, in part because he was romantically involved with the man’s wife.

During his murder trial, a prosecutor likened Peck’s actions to those of King David, according to one news account. In the Bible, King David sent his loyal soldier Uriah into combat to be killed so that David could be with Uriah’s wife, Bathsheba.

Originally facing the death penalty, Peck was instead sentenced to life in prison after his conviction. He later appealed the ruling on the grounds that an FBI agent offered shaky testimony at his trial. Peck was granted parole at some point, although it’s not immediately clear under what circumstances and when. Under Tennessee law, a person sentenced to life could become eligible for parole after serving 51 years.

But Peck’s legal troubles, according to court records and early news reports, may have started even before the murder charge.

At the time of his conviction, Peck was reportedly on the run from authorities in Louisiana and California, the latter of which wanted him in connection with two homicides, one in Orange County and the other in Van Nuys.

Another news story from the time quoted a local sheriff saying Peck belonged to a California motorcycle gang and fled to Tennessee because he could get a driver’s license there without being fingerprinted.

Prosecutors at his trial argued that Peck was able to elude authorities for so long, in part, by using different aliases, including Jerry McCarthy, Joe Orozco — and Mark Corbett.