If law is not just enacted rules but includes principles embedded in the moral fabric of a legal order, then how does a judge figure out what the law requires in a hard case? Dworkin's answer is among the most elegant philosophical proposals of the last century.
He asks us to imagine a judge he calls Hercules, not an actual judge but an idealized one, with superhuman patience, intelligence, and philosophical sophistication. What would Hercules do when faced with a hard case?
He would not simply look up the statute and apply it mechanically. He would not simply impose his personal moral views. Instead, he would construct what Dworkin calls the best interpretation of the legal materials available to him, statutes, precedents, constitutional provisions, legal principles, taking them as a whole and asking: what theory of law, what set of principles, makes the best sense of this body of material, and what does that theory imply for this case?
The key word is "best." Dworkin's interpretive judge is trying to achieve two things simultaneously: fit (the interpretation must account for the existing legal materials, you can't just ignore inconvenient precedents) and justification (among interpretations that fit, you choose the one that presents the law in its best moral light). Neither fit nor justification is sufficient alone. An interpretation that fits everything but is morally monstrous is not the best interpretation; an interpretation that would be morally ideal but ignores half the case law fails the fit criterion.
The chain novel analogy is brilliant. Imagine a group of novelists writing a chain novel: each writer receives what the previous writers have written and must add the next chapter. The task is not simply to continue the story in any direction, the writer must understand the existing chapters well enough to produce a contribution that fits the novel as so far written while also making it the best novel it can be. They can't change what has already been written; they must work within those constraints. But within those constraints, they are genuinely creating, contributing their own judgment about where the story should go.
This is exactly what a Dworkinian judge does. The legal materials already written (statutes, precedents, constitution) constrain interpretation. But within those constraints, the judge is genuinely adding to the law by choosing the interpretation that makes it the best it can be. The judge is not discovering pre-existing facts, and she is not making arbitrary policy choices, she is engaged in principled interpretation of a collaborative, ongoing practice.
Dworkin calls his overall view law as integrity. Integrity means that the law should speak with one consistent moral voice, the principles underlying legal decisions in one area should be consistent with those in others, so that the law treats all citizens as being governed by a coherent set of principles rather than by a series of disconnected political compromises. A government that has integrity treats each citizen as an equal bearer of rights, applying the same principles across all cases rather than making ad hoc exceptions.
The political implication Dworkin draws is striking: law as integrity means that individuals have rights as trumps against majoritarian politics. Even if a majority wants a law that would violate someone's rights, that law cannot be constitutionally legitimate, because rights are part of the best interpretation of the legal order, not just add-ons that majorities can waive when inconvenient.