Turn state's evidence

A criminal turns state's evidence by admitting guilt and testifying as a witness for the state against their associate(s) or accomplice(s),^[1] often in exchange for leniency in sentencing or immunity from prosecution.^[2] The testimony of a witness who testifies against co-conspirator(s) may be important evidence.^[2]

According to a 2008 United Nations Office on Drugs and Crime document, persons who turn state's evidence "are known by a variety of names, including cooperating witnesses, crown witnesses, snitches, witness collaborators, justice collaborators, state witnesses, "supergrasses", macarons and pentiti (Italian for 'those who have repented')."^[3]

^ Pomeroy, John Norton (1876). "State's Evidence". In Barnard, Frederick A. P. (ed.). Johnson's new universal cyclopædia a scientific and popular treasury of useful knowledge. New York; Pittsburgh, Pa.: A. J. Johnson & son. p. 495‒496.
^ ^a ^b Howard Abadinsky, Organized Crime (9th ed: Cengage Learning, 2010), p. 368.
^ "Good practices for the protection of witnesses in criminal proceedings involving organized crime" (PDF). United Nations Office on Drugs and Crime. 2008. p. 19.

[pomeroy1876-1] Pomeroy, John Norton (1876). "State's Evidence". In Barnard, Frederick A. P. (ed.). Johnson's new universal cyclopædia a scientific and popular treasury of useful knowledge. New York; Pittsburgh, Pa.: A. J. Johnson & son. p. 495‒496.

[Abadinsky-2] Howard Abadinsky, Organized Crime (9th ed: Cengage Learning, 2010), p. 368.

[3] "Good practices for the protection of witnesses in criminal proceedings involving organized crime" (PDF). United Nations Office on Drugs and Crime. 2008. p. 19.

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