[The talk of license plates threw him for a moment. He barely had a grasp on what a license plate was, but he hadn't realised that inmates of prisons contemporary to Valmont were expected to do that sort of labour for the outside world.]

No. Inmates here are expected to work for the rest of the Barge - in the kitchens, or the Infirmary, or in custodial services.

[He half-smiled.]

...and you must forgive me. I too have been to prison before, but all I was expected to do was waste away and perhaps die. There was little opportunity for gainful employment.