Brian Leiter (University of Texas at Austin – School of Law & Department of Philosophy) has posted Explaining Theoretical Disagreement on SSRN. Here is the abstract:
Shapiro (2007) has recently argued that Dworkin posed a new objection to legal positivism in Law’s Empire, to which positivists, he says, have not adequately responded. Positivists, the objection goes, have no satisfactory account of what Dworkin calls “theoretical disagreement” about law, that is, disagreement about “the grounds of law” or what positivists would call the criteria of legal validity. I agree with Shapiro that the critique is new, and disagree that it has not been met. Positivism can not offer an explanation that preserves the “face value” of theoretical disagreements, because the only intelligible dispute about the criteria of legal validity is an empirical or “head count” dispute, i.e., a dispute about what judges are doing, and how many of them are doing it (since it is the actual practice of officials and their attitudes towards that practice that fixes the criteria of legal validity according to the positivist).
Positivism, however, has two other explanations for theoretical disagreement, which “explain away” rather than preserve the “face value” disagreement. According to positivists, either theoretical disagreements are disingenuous, in the sense that the parties, consciously or unconsciously, are really trying to change the law, that is, they are trying to say, as Dworkin puts it, “what it should be” not “what the law is”; or they are simply in error, that is, they honestly think there is a fact of the matter about what the grounds of law are, and thus what the law is, in the context of their disagreement, but they are mistaken, because, in truth, there is no fact of the matter about the grounds of law in this instance precisely because there is no convergent practice of behavior among officials constituting a Rule of Recognition on this point. The “Disingenuity” and “Error Theory” accounts of theoretical disagreement are explored, with attention to the theoretical desiderata (e.g., simplicity, consilience, methodological conservativism) at stake in choosing between competing explanatory theories. Particular attention is given to the best explanation for Riggs v. Palmer in light of the actual historical context of the decision and other opinions by the Riggs judges in contemporaneous cases.
And a bit more from the text:
“Realist” explanations for the disagreement in Riggs, dispensing as they do with the Face Value of the dispute, are the flip side of the Disingenuity Accounts noted earlier. They do not necessarily suppose that the jurists are aware that there is no settled law in support of their view; rather, the jurists may simply be motivated subconsciously by their moral view of the merits, such that they convince themselves of the legal propriety of their preferred outcome. Or perhaps they lack even a subconscious awareness of the absence of settled law? In that case, the Error Theory Account explains why they talk as if there were a fact of the matter about the applicable criteria of legal validity. Of course, given their moral views of the merits, it should hardly be surprising that they make a systematic mistake about the nature of law at a certain rarefied level of abstraction. In any case, what the preceding shows, rather clearly, is that when Dworkin declares “there is no positive evidence of any kind that when…judges seem to be disagreeing about the law they are really keeping their fingers crossed”103 (as the Disingenuity Account would have it), what he really ought to have said is, “There may be lots of evidence, but I have made no effort to consider any of it.”
Highly recommended.