square john

noun

noun

Slang A prisoner who generally obeys the rules and avoids trouble.

Occasionally reputable persons, or "square johns," commit a felony of the type that leads to arrest […]1987, John Irwin, The Jail: Managing the Underclass in American Society, page 38:
Like thieves, square johns are a shrinking proportion of the American inmate population.2017, David Musick, Kristine Gunsaulus-Musick, American Prisons: Their Past, Present and Future, page 27:

Entry derived from the Wiktionary, under licence CC BY-SA 4.0 — list of authors.