cold case

American  

[kohld keys] / ˈkoʊld ˈkeɪs /

noun

1. a criminal investigation that has remained unsolved for an extended period of time.

   This year's award recipient is a state trooper whose work helped close a cold case from 1983.

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Etymology

Origin of cold case

First recorded in 1970–75

Example Sentences

In recent years, when a new break in a cold case makes headlines, it’s often because of updated genealogy tools or forensic detection technology.

From Slate • Apr. 6, 2026

“While this was classified as a cold case, investigators and prosecutors never stopped in their relentless pursuit of justice, reaffirming our commitment to holding people accountable for the crimes they are accused of committing.”

From Los Angeles Times • Feb. 10, 2026

Last week, the Nanterre cold case unit launched a broader investigation into Pelicot's "criminal trajectories" to identify other possible crimes and victims.

From Barron's • Jan. 19, 2026

The breakthrough comes just weeks after the release of the HBO docuseries The Yogurt Shop Murders last month, which revisited the cold case.

From Salon • Sep. 28, 2025

"If this mystery is about ice cream," Bess said, "does that make it a cold case?"

From "Scream for Ice Cream: Nancy Drew and the Clue Crew, #2" by Carolyn Keene