Green’s Dictionary of Slang

perp n.

[abbr. SE perpetrator]

1. (orig. US) a perpetrator, an accused criminal.

[US]Thomas Co. Cat. (Colby, KS) 26 Sept. 3: Blow me,. there wasn’t a single varmint to be seen [...] ’cept the dead perp that Bill had plugged through the head.
[US]Sun (NY) 26 Dec. 5/3: ‘Yer a liar, ye little perp,’ cried Sniffles indignantly.
[US]N. De Mille Smack Man (1991) 91: If we bring in this perp legal-like, [...] we need a case for the DA.
[US]H. Gould Fort Apache, The Bronx 10: They weren’t looking for leads because there would be no problem getting the perps on this case.
[US]D. Woodrell Muscle for the Wing 53: This thing is goin’ to be a full-tilt fuckin’ boogie ’til we find the perp, dig?
[US]S. Morgan Homeboy 72: By then the ‘perp’ [...] was long gone around the corner.
[US](con. 1970s) G. Pelecanos King Suckerman (1998) 185: The perps left plenty of prints.
[US]D. Hecht Skull Session 370: The perp or perps did the deed and bagged up the remains.
[UK]Indep. on Sun. 17 Oct. 23: The perp said ‘Stick ’em up’.
[UK]N. Griffiths Sheepshagger 238: That’s all yew are to them, mun, a criminal. A perp. Nothin else.
[US]C. Goffard Snitch Jacket 137: I know you dig the brothers-in-blue parlance, partner, but he ain’t a ‘perp’ till he’s done something.
[US](con. 1973) C. Stella Johnny Porno 201: Five years ago he had killed a perp.
[Aus] A. Bergen ‘Dread Fellow Churls’ in Crime Factory: Hard Labour [ebook] I never suspected the perp’s dress-sense would hurt my eyes.
[UK]K. Sampson Killing Pool 87: It galls me to have a perp laying down terms and conditions — a perp we have wrapped up so tight his balls are squeaking.
[US]D. Winslow The Force [ebook] The Haitians [...] found the perp still on the rooftop and tossed him off into the back alley.
[Aus]G. Gilmore Class Act [ebook] ‘The serious bit about who killed the bloke [...] The perp’.
[US]D. Winslow ‘Broken’ in Broken 12: ‘The perp shot the woman and then himself’.

2. (US black) one who is pretending or faking.

[US]G. Smitherman Black Talk.

3. (US drugs) fake crack cocaine consisting of baking soda and candle wax [ext. of sense 2].

[US]ONDCP Street Terms 16: Perp — Fake crack made of candle wax and baking soda.

In compounds

perp walk (n.)

a walk, e.g. that taken between a police car and a police station or into a law court, by a prisoner or suspect in custody.

[US]Indiana Gaz. (Indiana, PA) 10 May 2/1: Legal experts [...] agree that the president would have been better off doing the perp walk into the grand jury.
Standard-Speaker Hazleton, PA) 6 Mar. 15/2: Just about every local television station in the nation indulges in what is called in the trade ‘the perp walk.’ Usually with the co-operation of the police, the press knows when the alleged perpetrator is to be walked to the police station, and with cameras on, he or she is shown in handcuffs on the evening news .
[US]J. Stahl Plainclothes Naked (2002) 265: Massive shoulders hunched, a copy of Mademoiselle raised in front of his face, McCardle did the perp walk [...] to the sliding doors of the police station.
[US]Simon & Burns ‘Transitions’ Wire ser. 5 ep. 4 [TV script] Find the State’s Attotrney. He set up a perp walk for Clay Davis outside the Grand Jury today.
[US]N. Johnson ‘Corpse by Any Other Name’ in Pulp Ink [ebook] They had McCrea doing the perp walk and everything.
[US]D. Winslow The Force [ebook] ‘You have to do that? [...] Make him do the perp walk?’.
[US]S.M. Jones Lives Laid Away [ebook] I was the one who perp walked Duke Ducane into the 14th Precinct.
[US]C. Stella Joey Piss Pot 296: ‘Shame you didn’t smile during your perp walk. CNN was there filming’.

In phrases

perped down (abbr.)

(US und.) looking obviously like a gangster.

[US]W.D. Myers Autobiog. of My Dead Brother 57: He was in street clothes and perped down, with his pants hanging low on his hips and his sneakers open.