Crime

Men Receive Lengthy Prison Sentences for 2023 Murder of Colorado Jeweler

CrimeOct 15, 2025

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.

Colorado jeweler Peter Damian Arguello
Peter Damian Arguello, who owned and operated Peter Damian Fine Jewelry & Antiques in Wheat Ridge, Colorado, for almost two decades, was shot and killed in his store in November 2023. The men convicted in the case earlier this year have been sentenced. (Photo courtesy of the Wheat Ridge Police Department)
Golden, Colo.—The two men found guilty in the 2023 robbery and murder of Wheat Ridge, Colorado, jeweler Peter Damian Arguello will spend a long time behind bars. 

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.  

 Related stories will be right here … 

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

GemFair x DBL Toi et Moi Ring
CollectionsJan 27, 2026
De Beers London, GemFair Debut New Collection Highlighting Artisanal Diamonds

The collection marks the first time GemFair’s artisanal diamonds will be brought directly to consumers.

Montana sapphire
SourcingJan 27, 2026
GemGuide Launches Pricing for Montana Sapphires

The initial charts are for blue, teal, and green material, each grouped into three charts categorized as good, fine, and extra fine.

Clientbook
TechnologyJan 27, 2026
Clientbook Launches Appointment Booking Tool

The new tool can assign the appropriate associate based on the client or appointment type and automate personalized text message follow-ups.

JamAlert 1872x1052.png
Brought to you by
How Jewelers Can Fight Back Against Cell Jammers

Criminals are using cell jammers to disable alarms, but new technology like JamAlert™ can stop them.

Columbia Gem House celestial shapes
SourcingJan 26, 2026
Tucson Preview 2026: Earthy Tones and Innovative Shapes

Buyers are expected to gravitate toward gemstones that have a little something special, just like last year.

Weekly QuizJan 22, 2026
This Week’s Quiz
Test your jewelry news knowledge by answering these questions.
Take the Quiz
Diamond center in Saurimo, Angola
SourcingJan 26, 2026
Angolan Diamond Cos. Join NDC as Rio Tinto, Murowa Exit

Endiama and Sodiam will contribute money to the marketing of natural diamonds as new members of the Natural Diamond Council.

Francesca’s boutique
MajorsJan 26, 2026
Francesca’s To Close All Stores

The retailer operates more than 450 boutiques across 45 states, according to its website.

Recipients Collage 2025 - NJ (1872 x 1050 px) (1872 x 1052 px).png
Brought to you by
Impacting Tomorrow Today

How Jewelers of America’s 20 Under 40 are leading to ensure a brighter future for the jewelry industry.

Thomas Davis, Monalisa DePina, Jamie Batiste, Namwezi Nicole Batumike, Lavina Hunt-Lewis
MajorsJan 26, 2026
BIJC Names 5 New Board Members

The new members’ skills span communications, business development, advocacy, and industry leadership.

Tiffany & Co. Celebrating Love Stories Since 1837 Campaign
CollectionsJan 26, 2026
Tiffany & Co. Celebrates 189 Years of Love Stories

The jeweler’s 2026 Valentine’s Day campaign, “Celebrating Love Stories Since 1837,” includes a short firm starring actress Adria Arjona.

DCA colored gemstone course
GradingJan 26, 2026
DCA Updates Colored Gemstone Course

The new features include interactive flashcards and scenario-based roleplay with AI tools.

Deutsch & Deutsch jewelers team
MajorsJan 23, 2026
Watches of Switzerland Acquires 4-Store Jewelry Chain in Texas

Family-owned jewelry and watch retailer Deutsch & Deutsch has stores in El Paso, Laredo, McAllen, and Victoria.

Baume & Mercier Riviera 10812 pink watch
WatchesJan 23, 2026
Damiani Group to Acquire Baume & Mercier

The Italian luxury company purchased the nearly 200-year-old Swiss watch brand from Richemont.

Martin Katz snowflake earrings
TrendsJan 23, 2026
Martin Katz’s Earrings Call to Mind Wintry Weather

Micro-set with hundreds of diamonds, these snowflake earrings recreate “winter’s most elegant silhouette,” and are our Piece of the Week.

Ella Blum
MajorsJan 23, 2026
Rembrandt Charms Names New Director of Creative, Brand Strategy

Ella Blum was appointed to the newly created role.

National-Jeweler_1872x1502_B copy.png
Supplier BulletinJan 22, 2026
The Rise of Centralized Sourcing in the Colored Gemstone Market

Sponsored by RapNet

Lugano Diamonds Greenwich Connecticut store
MajorsJan 22, 2026
Lugano Diamonds Finds a Buyer

Investment firm Enhanced Retail Funding, a division of Gordon Brothers, was the successful bidder.

A Diamond Is Forever book
SourcingJan 22, 2026
De Beers To Release ‘A Diamond Is Forever’ Book

It explores the history of the iconic tagline and the company’s strategy to redefine the role of diamonds in society.

Sindhu Culas
MajorsJan 22, 2026
Swarovski Appoints New North America President

Retail veteran Sindhu Culas has stepped into the role.

Taylor Burgess
MajorsJan 22, 2026
Stuller Names New Chief Merchandising, Marketing, Sales Officer

Taylor Burgess, who has been at Stuller since 2013, was promoted to the newly created role.

My Next Question podcast with Sherry Smith and Edahn Golan
PodcastsJan 21, 2026
Episode 1: High Gold Prices, the Diamond Dilemma, & What’s Next

Was 2025 a good year for jewelers? Did lab-grown diamonds outsell natural? Find out on the first episode of the “My Next Question” podcast.

Jules Kim of Bijules, Sophie Howard of By Pariah, Jade Ruzzo, Joy Haugaard of Lionheart, Vanessa Fernández of Vanessa Fernández Studio, Hiba Husayni of Zahn-Z
EditorsJan 21, 2026
6 Jewelry Designers Poised to Have a Breakout Year in 2026

Whether you recognize their jewels or are just discovering them now, these designers’ talent and vision make them ones to watch this year.

Felice Korr Morris
IndependentsJan 21, 2026
Delaware Jeweler Felice Morris Dies at 91

Morris’ most cherished role was being a mother and grandmother, her family said.

Bulgari Vimini Collection Campaign
CollectionsJan 21, 2026
Bulgari Weaves New Collection of ‘Vimini’ Creations

“Vimini” is the first chapter of the “Bulgari Eternal” collection that merges archival pieces with modern creations.

The Ritz-Carlton Half Moon Bay California
Events & AwardsJan 21, 2026
Jewelers Mutual’s ‘Conversations’ Retreat Returns to Discuss AI

The third edition will be held in Half Moon Bay, California, in April.

Hiba Husayni, Jules Kim, Johnny Nelson, Dorian Webb, Lorraine West
Events & AwardsJan 20, 2026
These Are the 5 Finalists for the David Yurman Gem Awards Grant

The grant is in its first year and was created to recognize an exceptional fine jewelry designer whose star is on the rise.

Emmanuel Raheb, National Jeweler columnist and CEO of Smart Age Solutions
ColumnistsJan 20, 2026
First-Party Data Is the Most Valuable Asset Jewelers Have in 2026

Data built on trust, not tracking, will be key to success going forward, as the era of “borrowed attention” ends, Emmanuel Raheb writes.

×

This site uses cookies to give you the best online experience. By continuing to use & browse this site, we assume you agree to our Privacy Policy