GOLDEN, Colo. (Oct. 13, 2025) – The two men responsible for the 2023 murder and robbery of Wheat Ridge jewelry store owner Peter Arguello have now both been convicted and sentenced to lengthy prison terms.
The robbery occurred on November 29, 2023, when the men entered Peter Damian Fine Jewelry & Antiques in Wheat Ridge. During the robbery, Mr. Arguello was kidnapped, assaulted, and fatally shot by Charles Shay.
In August, Shay was convicted by a Jefferson County jury of ten counts, including First Degree Murder, and was later determined to be a habitual criminal under Colorado law, based on six prior felony convictions.
Weeks later, a separate jury convicted Michael James McCormack on all five counts against him, including Felony Murder and Aggravated Robbery. Prosecutors and the victim’s family argued that McCormack gained Mr. Arguello’s trust and used his access to the business to target him. During sentencing, a family friend told the court that McCormack “kept tabs on Peter and the store—like a lurking, cunning predator.”
On September 10, Shay was sentenced to life without the possibility of parole plus 120 years. McCormack was sentenced earlier today to 75 years in prison.
At both sentencing hearings, Mr. Arguello’s family and friends spoke about the profound loss they’ve endured and the immeasurable impact his murder has had on their lives. They described Peter as a devoted family man, a proud small business owner, and a beloved member of the Wheat Ridge community.
“Our 20-year-old business was destroyed in minutes,” said Teresa Casillas, Peter’s wife. “Peter was the reason customers came to the store. After his murder, it was impossible to keep it open. He was committed to working at least 10 more years because he loved his little shop and took so much pride in its treasures. Unlike most of us, going to work was fun for him.”
She reflected on the family’s long wait for justice after two years of court hearings.
“I am angry at the system that did not protect us from him,” she said. “I am angry at the delays, the legal posturing, and the upcoming appeals. When do we get to grieve? We know that sentencing doesn’t bring Peter back, but it does keep this man from hurting other families.”
“Peter Arguello was an innocent victim and a beloved member of this community whose life was stolen in a senseless act of violence,” said Chief Deputy District Attorney Chandler Grant. “These sentences bring accountability, honor the strength of his family and community, and reflect the tireless work of our law enforcement partners to ensure justice for Peter and his loved ones.”
Mrs. Casillas also expressed deep gratitude to the investigators and prosecutors who pursued justice in Peter’s name.
“We are forever grateful for the dedication and commitment of the Jefferson County District Attorney’s Office, the Wheat Ridge Police, and all the professionals who worked so hard to get justice for Peter,” she said. “We have been showered with love and support from the moment Peter was attacked until today. Because of you, we stand here now.”