Green’s Dictionary of Slang

(US Und.) a State police officer; also attrib.

1934		J. O’Hara Appointment in Samarra 186: Some days the gang would hop a wagon [. . .] and ride out to the state police barracks and watch the staties drill.
1950		Goldin et al. DAUL 209/1: Statey. (Carnival) a state trooper.
1989		Boston Globe 1 Jan. Globe 1: [headline] Flynn inflames the Staties.
2000		G.V. Higgins At End of Day (2001) 94: One of them was gonna get himself grabbed by some kid Statie two weeks outta the academy.
2001		Boston Herald 5 June [headline] Connolly lawyers to say statie tipped Mob.
2017		S.M. Jones August Snow [ebook] ‘Some very pissed off Staties’.
2021		J. Ellroy Widespread Panic 147: I flahed my Statie badge.