Back to the song, and the judge's left shoulder, I'm not so sure that it's more involved than that the judge takes the whole thing lightly, is already on his way out the door, and tosses off a sentence en passant, as it were. In this reading the "left" is merely there to fill in the line, and to give a visual appeal to the song. Could have been the right shoulder just as easily, if that's the case.

Dave Oesterreich