Prior to 1960, legal scholars invoked economics only in a handful of specialized contexts -- mostly antitrust and taxation. But it was not generally thought that economic science had much of anything useful to say about the law generally.Then, in the early 1960s, Guido Calabresi and Ronald Coase published a couple of papers that a lot of people found pretty darned interesting.
Richard Posner was one of those people. Within about a decade thereafter, he had written a massive treatise-textbook that attempted to apply (Chicago-school) economic insights to almost the entirety of the law, in part relying on Calabresi's insights on risk allocation and Coase's famous theorem about what happens in a world with no transaction costs.
That treatise-textbook is now in its fifth edition, and you're looking at the Amazon page for it. It would be hard to name a more influential work in the field of law and economics -- and even today, as Posner himself will gladly tell you, although there are a few other _textbooks_ on the topic, there are still no other _treatises_.
Posner's scope is breathtaking. Not content to limit himself to the usual array of legal topics (property, torts, contracts, criminal law, legal procedure, and so forth), he also manages to devote portions of his text to, e.g., sex and marriage, surrogate motherhood, prostitution, homosexuality, and a host of other controversial and/or marginal topics you don't typically encounter in an economics text.
The typical reader will probably not find him altogether persuasive on these topics. In fact, if you're anything like me, you'll probably wind up shaking your head in sheer wonderment: how is it possible for someone to be so brilliantly incisive on one page and so infuriatingly obtuse on the next?
But don't assume Posner is the one who's wrong. Don't misunderstand me; I think he _is_ sometimes the one who's wrong. But even then, his arguments are something to be reckoned with, not to be easily dismissed. (Nor is he _ever_ simply "obtuse.")
For the most part I think the book is a success in its more modest aim. In the fifth edition, Posner ends his opening chapter with a short reply to critics of the law and economics movement; with much of what he has to say here I can wholeheartedly agree. His work should, as he notes, be of _some_ interest to anyone who thinks Kaldor-Hicks efficiency/potential Pareto improvement plays any role whatsoever in setting policies. (I don't personally think it plays or should play much role at all, but I can agree with the point as Posner has stated it.) And Posner notes, quite unobjectionably, that the entire field should not be rejected merely because one does not accept the views of its most aggressive exponents.
But make no mistake, Posner _is_ one of its most aggressive exponents, and the apparent modesty of his aims is somewhat disingenuous: he is not merely trying to find out what economics can say about the law but to tell us that it can say quite a lot indeed. And it is here that I find him ultimately unconvincing on a number of points.
(To take one well-known example, I don't think Posner's discussion of the famous "Hand formula" captures what Judge Billings Learned Hand meant by it, and at any rate the formula is not as useful as Posner seems to think it is. There is some good discussion of the Hand formula by Richard Wright in _Philosophical Foundations of Tort Law_, and in general Posner has been roundly and in some respects successfully criticized by a wide range of scholars from Ronald Dworkin to Gary Schwartz.)
But there is no getting around this massive work, and it absolutely cannot be lightly dismissed. On the contrary, the thing bristles with fine insights and obviously massive legal and economic erudition; most of it will repay close reading even for the reader who ends up disagreeing. If you have any interest in the field of law and economics, you really ought to read this book _sometime_.
