A Jefferson County jury found a 42-year-old man guilty of robbing and murdering a jewelry store owner in Wheat Ridge in 2023.

Following a seven-day trial and nearly three days of deliberation, the jury found Charles Robinson Shay guilty of 10 charges including first-degree murder, second-degree murder, aggravated robbery and motor vehicle theft on Wednesday afternoon, according to a news release from the First Judicial District Attorney’s Office.

Peter Arguello was murdered at his jewelry store in the 7200 block of West 38th Avenue on Nov. 29, 2023.

The front business door is locked and customers have to be buzzed inside. Surveillance showed Arguello walking to the front door and letting a man inside. Once inside, the man appeared to be looking at stuff at the counter and then pulled a gun on Arguello and forced him to the rear of the store, according to court records. The person was later identified as Shay.

A second man, later identified as Michael McCormack entered the back of the store. He was later arrested and charged with second-degree murder, second-degree kidnapping, aggravated robbery and motor vehicle theft.

Witnesses saw two people leave Arguello’s store through the back door and get into a red pickup truck, according to arrest records. Police said they later recovered that truck in Centennial after it had been set on fire and heavily damaged. Two hats were found in the bed of the truck that matched the suspect hats in the surveillance videos.

Shay was initially arrested after a burglary at the store on Dec. 26, 2023, around a month after the murder. He claimed to have entered the store after he heard about the murder because he thought it was a good theft opportunity.

DNA on a pair of flex cuffs eventually linked Shay to the murder of Arguello.

After the jury returned the guilty verdict on Wednesday, they were then asked to complete the habitual criminal phase of the trial. During the phase, jurors heard additional evidence regarding Shay’s prior felony convictions under Colorado’s Habitual Criminal statute, according to the release.

After an hour of deliberation, jurors found Shay guilty of an 11th count — habitual criminal with six prior felony convictions.

The habitual criminal conviction may lead to a sentence enhancer if not found constitutionally excessive under the Eighth Amendment.

Shay is scheduled to be sentenced on Sept. 10. McCormack is set for trial on Aug. 22. 

The Denver Gazette’s news partner, 9NEWS, contributed to this report