As in the Clerk's portrait, the depiction of the Sergeant of the Law is fairly neutral. Yes, there's a little bit of criticism – we learn that the Sergeant seems busier than he really is, suggesting that he's trying very hard to look like he's earning his paycheck when, in fact, he might be kind of lazy. But the generally favorable impression we get of the Sergeant of the Law from what we learn of his competence balances out this gentle satire.