red band

From the red bands worn on their arms.

red band (plural red bands)

(UK) A trusty; a trusted prisoner given special privileges.
- 1967, Harley Cronin, The Screw Turns, page 51:
  It was an extension of the American Trusty system, as was the appointment of other selected prisoners to be 'Red Bands'.
- 2012, Charlie Seiga, Killer, page 75:
  A red band was a trusty prisoner who could go anywhere in the prison. His job was taking mail to the main office and delivering any other messages for the screws or staff. Red bands had a bad name amongst the rest of the prisoners.

From the red color of the horizontal bar on the cinematic rating screen at the start of the show.

red band (not comparable)

English