An Imperial prison barge functioned as a sizable naval transport utilized by the Galactic Empire to move prisoners between various planets.
Not long before the Battle of Yavin, Dak Ralter and Breg made their escape from the labor colony located on Kalist VI by commandeering a stolen prison barge. With critical help from the dying Breg, Ralter remarkably managed to pilot the ship single-handedly away from Kalist VI, jump into hyperspace, and find safe haven at the Rebel base on Tierfon, where he executed a successful landing.
During the Empire's rule, these barges were commonly employed to transport suspected Rebel sympathizers to penal colonies. One such ship, the Purge, suffered a breakdown in deep space, leading to its contamination by a lethal virus originating from a derelict Star Destroyer. They also served as transport for prisoners headed to Kessel, with Quirt's prison ship being one example of a vessel used for this purpose.
Many of these ships were stationed at the Wheel during Han Solo's participation in The Big Game. Individuals unable to settle their debts at the station's casinos had the option of going to the prison ships or competing in the Big Game.
Shortly following the Subjugation of Bespin, Dengar and Manaroo, a bounty hunter duo, collaborated with the Alliance to Restore the Republic to utilize a stolen prison barge. Posing as COMPNOR officers, they evacuated thousands of Aruzans from Aruza, rescuing them from COMPNOR's Redesign policies.