I first heard the song from the Clancys in the early '60's. It never says they're in Dublin, just that they are "cousins" of Briscoe, apparently meaning The judge and defendant are both Jewish, and the cop is an idiot. If Briscoe is more contemporary than the time the song decribes, it may be that the Clancys (or someone else) threw that part in for fun, after the song was written.