The Prison Bus is very different to the normal Bus as it is shorter, faster and heavily armored for prison-mate transportation and protection for the Alderney State Correctional Facility. The bus' design is comparable to that of a typical American school bus, but features barred windows intended to keep transported inmates inside. Being based on the Yankee although lacking any badging, the cowl (hood) design is based on the International Harvester S-Series, although lacking its distinctive power bulge. The headlights and grille bear a loose resemblance to the Chevrolet Kodiak. As for the bus body, the design is loosely based on the Blue Bird CV200 body.
The Prison Bus performs much better than the Bus due to its shorter wheelbase and lighter construction. It has moderately good suspension and steering for a vehicle of its class, but given it is an armored vehicle it suffers from poor acceleration, although it can achieve considerably good top speeds. Its still heavy weight also allows for the ability to push aside smaller vehicles with ease. Also the Prison Bus is 4WD, which makes it a good performer off-road and on rough uneven terrain.
In single player, the Prison Bus appears in the mission "Off Route" where Johnny must hijack it full of inmates, lose a three-star wanted level and then drive it down to Acter Industrial Park, after which it is pushed into the ocean when the inmates have disembarked; during the mission, this bus is depicted to be impervious to damage. The bus also can be seen in the mission "Get Lost" when the player must break into the Alderney State Correctional Facility and then when he is breaking out. A video demonstrating how to obtain the Prison Bus can he seen here.
There is only one way to obtain this vehicle; the player must park the vehicle at a safehouse parking lot, move a safe distance away, and then kill themselves. You can only do this when doing the mission "Off Route".
In multiplayer, players can race the prison buses.
The Prison Bus, along with the Annihilator, are the only police vehicles with a radio in single player.
The Prison Bus seems to be roughly based of of the cab of the Yankee because it has the same engine and engine layout and the same "reversed" method of the way the hood opens.