Overview
As used by some criminologists and others who study criminal investigations (including mystery writers), a perfect crime goes unsolved not because of incompetence in the investigation, but because of the cleverness and skill of the criminal. I.e., the defining factor is the primary causative influence of the criminal's ability to avoid investigation and reprisal, and not so much the ability of the investigating authority to perform its duties.
Would-be perfect crimes are a popular subject in crime fiction and movies. They include Rope, Double Indemnity, Strangers on a Train, The Postman Always Rings Twice, Witness for the Prosecution, and Dial M for Murder.
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