Men Receive Lengthy Prison Sentences for 2023 Murder of Colorado Jeweler
Charles Robinson Shay was sentenced to life in prison plus 120 years while his accomplice, Michael James McCormack, got 75 years.

The Colorado First Judicial District Attorney’s Office announced that on Monday, Michael James McCormack, 51, was sentenced to 75 years in prison after being found guilty of felony murder and aggravated robbery, among other charges.
The other man charged in the case, 42-year-old Charles Robinson Shay, was found guilty in a separate trial of 10 counts in connection with Arguello’s death, including first-degree murder, second-degree kidnapping, and aggravated robbery.
Jurors also found Shay, who has six prior felony convictions, to be a “habitual criminal” under Colorado law, a charge that can lead to longer prison sentences.
Shay was sentenced to life without the possibility of parole plus 120 years on Sept. 10, the DA’s office said.
Arguello, 64, was the owner of Peter Damian Fine Jewelry & Antiques, a store he opened in 2007.
According to the DA’s office, Arguello’s wife, Teresa Casillas, said during sentencing that after her husband’s death, they had to close their business because, “Peter was the reason customers came to the store.”
“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 said.
In a post on Facebook, the Wheat Ridge Police Department described the late jeweler as a friend, mentor, and father figure in the Wheat Ridge community.
“His shop was a welcoming, safe place where you were always greeted with a smile,” the post reads.
“Peter embodied the kind of optimism and compassion we try to exemplify in our community and in our police department … Justice will not bring Peter back, but we sincerely hope this outcome will allow Peter’s family to heal. They are part of our family now, forever and always. As we move forward, we honor his memory by living life with joy and kindness.”
Arguello was in his store on the morning of Nov. 29, 2023, when Shay and McCormack came in.
Prosecutors and Arguello’s family argued during trial that McCormack earned Arguello’s trust in order to gain access to the store and then target him, keeping tabs on the jeweler “like a lurking, cunning predator.”
During the robbery, it was Shay who bound Arguello with flex cuffs, assaulted him, and fatally shot him, the DA’s office said.
Both men were seen by witnesses fleeing through the back door and getting into a red Chevy Silverado—which police later determined had been stolen—that was found after it had been set on fire.
DNA found on the flex cuffs linked Shay to the crime, and he was formally charged in January 2024.
Police issued a warrant for McCormack on March 7, 2024, and arrested him on May 2 following a two-month search.
The Latest

“Jewelry Creators: Dynamic Duos and Generational Gems” highlights the relationships among 22 influential designers, brands, and gem dealers.

The AJS Spring 2027 show will be held in Savannah, Georgia, with future shows taking place in other Southeast cities.

The jewelry retailer plans to open 20 new stores this year and expand into new product categories.

Gain access to the most exclusive and coveted antique pieces from trusted dealers during Las Vegas Jewelry Week.

Flower motifs are the jewelry trend blooming amongst the new collections that debuted this spring.


The retailer reported an 8 percent decline in annual sales as it struggles under the weight of billions of dollars of debt.

The “Devil” drop earrings, our Piece of the Week, are part of designer Edina Kiss’ new namesake jewelry line that she will show at Couture.

Gain access to the most exclusive and coveted antique pieces from trusted dealers during Las Vegas Jewelry Week.

The “watchmaker of shapes” debuted the reworked version of the vintage sports car-inspired timepiece at Watches & Wonders.

As demand for jewelry retail coaching grows, the company has established a dedicated business coaching leadership team.

The “Mountings 2026-2027” catalog showcases Stuller’s largest and most diverse assortment to date with more than 400 new mounting styles.

Sally Morrison and Mark Klein discuss De Beers’ first beacon in 16 years and the mistake the industry made with lab-grown diamonds.

McKenzie spent 45 years with Spark Creations and is remembered for being kind, dedicated, and hardworking.

Rolex focused exclusively on the Oyster Perpetual this year, as the model is celebrating its 100th anniversary.

The luxury giant discussed the Middle East conflict and its transformation plans, hinting at a stronger jewelry presence in North America.

Kalpesh Jhaveri was re-elected as president for a third year.

“Diamond Divas,” a social media reality series by Shahla Karimi Jewelry, is nominated in the “Best Social: Fashion & Beauty” category.

The campaign seeks to reignite desire for natural diamond engagement rings by highlighting the “distinct character” of warm-toned diamonds.

Plus, how Saks Global’s bankruptcy affected the luxury giant’s first quarter.

Presented by Mason-Kay Jade, the summit, in its second year, will again be held during the Monterey Bay Jade Festival.

The group has announced its lineup of speakers and a new “Rising Stars” pavilion.

The “Carbon Form” collection explores the contrast between high and low materials, using rubber cord alongside 18-karat gold and gemstones.

The program provides essential funding to organizations for projects that enhance the jewelry industry.

The jewelry trade show is launching its first open-to-the-public event in Coconut Grove this November.

JSA is seeking information about the gunpoint robbery of a Kay Jewelers location in Oregon’s Washington Square Mall.

The top-performing watch models may be surprising, with Rolex and several popular pandemic-era picks notably absent from the top 20.

The “Scroll” toggle pendant, our Piece of the Week, opens to reveal a hidden message, mantra, or love letter written on washi paper.























