Cold case (criminology)

A cold case is a crime or an accident that has not yet been fully solved and is not the subject of a recent criminal investigation, but for which new information could emerge from new witness testimony, re-examined archives, new or retained material evidence, as well as fresh activities of the suspect. New technical methods developed after the case can be used on the surviving evidence to re-analyze the causes, often with conclusive results.

Typically, cold cases are violent or other major felony crimes, such as murder or rape which—unlike unsolved minor crimes—are generally not subject to a statute of limitations.

Sometimes disappearances can also be considered cold cases if the victim has not been seen or heard from for some time, such as the case of Natalee Holloway or the Beaumont Children.

About 35% of those cases are not really cold cases at all. Some cases become instantly cold when a seeming closed (solved) case is re-opened due to the discovery of new evidence pointing away from the original suspect(s). Other cases are cold when the crime is discovered well after the fact – for example, by the discovery of human remains. Some cases become classified cold cases when a case that had been originally ruled an accident or suicide is re-designated as a murder when new evidence emerges.

The John Christie murders is a notable case, when Timothy Evans was wrongly executed for the alleged murders of his wife and child. Many other bodies were later found in the house where they lived with Christie, and he was then executed for the crimes. The case helped a campaign against capital punishment in Britain.

A case is considered unsolved until a suspect has been identified, charged, and tried for the crime. A case that goes to trial and does not result in a conviction can also be kept on the books pending new evidence.

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