Edward Lazarus writes an interesting albeit incomplete article on Findlaw critiquing the law and economics movement’s reliance on the presumption of human rationality. Lazarus questions the movement not only based on recent Nobel winning scholarship (the prize was in economics, and not in peace, so it actually means something) that suggests that men act from both rational and irrational impulses, but also based on his assessment of how law and economics scholars like Judge Richard Posner have imposed their views in the place of existing law. This is a very powerful critique, and is one with which Posner would not disagree (other than in the conclusion that this is somehow wrong).
While Lazarus seems disturbed by the replacement of administrative judgments with the law-and-economics-influenced assumptions of judges, he does not reach the underlying problem of pragmatism--the results oriented jurisprudence which judges like Posner use to assert their view of the proper results in priority over the statutory text. Accordingly, for Posner, jurisprudence is not limited to interpretation of statutes, or even to filling in the "gaps" in statutes. Rather, if the legislature reaches an inefficient result, he believes that it is the role of the judge to fix it, even if such a result is in direct conflict with the statute.
If Lazarus thought more deeply about his critique, he would find that it is tied up in the larger problem of pragmatism. But critiquing pragmatism would require him to engage pragmatic liberal judges--judges like Justice Breyer, who subscribes to the theory that judges may impose their vision of the best result, but doesnt use anything like law and economics to moor his decisionmaking. It will be interesting to see if Lazarus is capable of being evenhanded enough to make the larger pragmatic critique, or whether the rant against law and economics is simply opposition to the imposition of one set of assumptions or preferences based on nothing more than his own subjective preferences.