Police shows

The police procedural, or police crime drama, is a subgenre of detective fiction that attempts to convincingly depict the activities of a police force as they investigate crimes. Although traditional detective novels usually concentrate on a single crime, police procedurals frequently depict investigations into several unrelated crimes in a single story. Traditional mysteries usually adhere to the convention of having the criminal's identity concealed until the climax (the so-called whodunit), whereas in police procedurals, the perpetrator's identity is often known to the audience from the outset (the inverted detective story). Police procedurals depict a number of police-related topics such as forensics, autopsies, the gathering of evidence, the use of search warrants, and interrogation.

The roots of the police procedural have been traced to at least the mid-1880s. Wilkie Collins's novel The Moonstone (1868), a tale of a Scotland Yard detective investigating the theft of a valuable diamond, has been described as perhaps the earliest clear example of the genre.

However, Lawrence Treat's 1945 novel V as in Victim is often cited, by Anthony Boucher (mystery critic for the New York Times Book Review) among others, as perhaps the first true police procedural. Another early example is Hillary Waugh's Last Seen Wearing ..., 1952. Even earlier examples from the 20th Century, predating Treat, include the novels Vultures in the Dark, 1925, and The Borrowed Shield, 1925, by Richard Enright, retired New York City Police Commissioner, Harness Bull, 1937, and Homicide, 1937, by former Southern California police officer Leslie T. White, P.C. Richardson's First Case, 1933, by Sir Basil Thomson, former Assistant Commissioner of Scotland Yard, and the short story collection Policeman's Lot, 1933, by former Buckinghamshire High Sheriff and Justice of the Peace Henry Wade.

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