stool pigeon

n.

1. Slang. A person acting as a decoy or as an informer, especially one who is a spy for the police.
2. A pigeon used as a decoy.

[From the practice of tying decoy pigeons to a stool to attract other pigeons.]

(stool PIJ-uhn)

noun
1. A person who works as a decoy or informer, especially for the police.
2. A pigeon used as a decoy.

Etymology
Of uncertain origin: apparently from the former practice of tying decoy pigeons to a stool; possibly from French estale or estal which referred to a pigeon used to entice a hawk into a net

Usage
"But (David Cooper) Nelson refused to identify the mysterious third party, saying, 'I'm no stool pigeon. I'd rather die than tell on the other fellow, a nice guy with a wonderful family.'" — Richard Melzer; First Man to Die in State's Gas Chamber Was Convicted by Valencia County Jury; The News-Bulletin (Belen, New Mexico); Jun 18, 2004.

"It's the onerous duty of this group to assess a stool pigeon's credibility, and then decide 'if it's in the public interest' to have that person testify." — Nick Pron; Should Authorities Listen to the Jailhouse Talk?; The Toronto Star (Canada); Jun 2, 2002.

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Spy or police informant. A stool pigeon betrays another and their confidences to the authorities.

noun

One who gives incriminating information about others: informant, informer, tattler, tattletale. Informal rat, tipster. Slang fink, snitch, snitcher, squealer, stoolie. See knowledge/ignorance, law.

A decoy or informer, especially a police spy. For example, Watch out for Doug; I'm sure he's a stool pigeon for the supervisor. This term alludes to a bird tied to a stool or similar perch in order to attract other birds, which will then be shot. However, one writer believes that stool is a variant for stale or stall, both nouns used for a decoy bird before 1500 or so. [c. 1820]

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