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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.


Etymology

Origin of cold case

First recorded in 1970–75

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Welsh actress Eve Myles is set to star in a crime drama inspired by the true story of a detective who solved the cold case murder of a 17-year-old girl in the 1980s.

From BBC

Still, experts say it’s far too early to call this a “cold case” and noted a break could come at any moment.

From Los Angeles Times

Schubert later rose to prominence for her role in the case against Joseph James DeAngelo — also known as the Golden State Killer — where she pioneered the use of DNA evidence in securing cold case convictions.

From Los Angeles Times

“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

"This prosecution and conviction some 27 years on from the original investigation shows the importance of cold case reviews and exploiting advances in technology," he said.

From BBC