A Washington man who fatally shot his ex-girlfriend and two other former high school classmates last July at a Seattle-area house party pleaded guilty Monday to the murders, the Snohomish County Prosecutor’s Office confirms to PEOPLE.
Allen Christopher Ivanov, 20, stood accused of using a recently purchased AR-15-style rifle to commit the July 30 murders at the party in Mukilteo, reports The Seattle Times.
His plea came one day before the prosecutor planned to announce whether to seek the death penalty in the case, according to The Herald of Everett.
Ivanov faces a mandatory sentence of life in prison when he is sentenced January 12.
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Killed in the attack were Jordan Ebner, Jake Long and Anna Bui, all 19. Ivanov pleaded guilty to three counts of aggravated first-degree murder in their deaths, plus two counts of attempted murder for allegedly shooting at others attending the party, according to charging documents obtained by PEOPLE.
The charge in the death of Bui, the former girlfriend with whom prosecutors say Ivanov had recently endured a breakup, also carried an allegation of domestic violence.
Ivanov was arrested nearly 100 miles away about 90 minutes after the shooting, and in an affidavit following his arrest, police wrote, “Ivanov states that everything that went on tonight was about a girl,” the Times reports.
His attorneys filed documents earlier this month suggesting there was evidence that Ivanov had untreated neurological problems and possible mental illness, and they urged additional study of their client as prosecutors weighed whether to seek the death penalty.
Ivanov’s defense attorney, Walter Peale, wrote that testing suggested Ivanov had the brain development of someone younger than his 19 years.
Before accepting Ivanov’s plea, Snohomish County Superior Court Judge Janice Ellis stressed in court that his admission left her no choice for sentencing other than life behind bars.
“You understand that is what the law requires?” she asked him. He indicated he did.
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Defense attorney Peale said the goal of the guilty plea was to keep his client from the possible death penalty, and that subsequent evaluations of Ivanov had judged him fit to make and accept that plea.
According to The Herald, Peale said there was “almost zero” chance Ivanov would have been acquitted of all charges at trial.
In a six-page letter written prior to the shooting, Ivanov had described his despair over the collapse of his relationship with his former girlfriend, and in rap lyrics sent from jail he bragged about her killing, The Herald reports.
“I knew she knew who I was ’cause I saw her face right before I pulled the trigger,” he wrote.