Adverse Selection in Insurance Markets: An Exaggerated Threat

The thesis of this Essay is that although theory demonstrates that adverse selection can occur, and some instances have certainly been documented, neither the theoretical models nor the empirical studies provide much support for its widespread importance in insurance markets. The nature of selection pressures turns out to be vastly more complicated than the rhetoric of courts and academic commentators would suggest. And while the economic theory of adverse selection in insurance markets has become enormously sophisticated, much of it is devoted to rarified analysis of the nature and existence of equilibria. It has thus managed to obscure some essential features of insurance demand that may undercut or even reverse the typical adverse selection results. In short, while adverse selection in insurance markets is clearly a possibility, it is often not the serious problem that it is taken to be. Courts, policymakers, and legal academics need to do much more than trumpet a concern for adverse selection as a justification for their preferred course of action. And economists need to develop less obscure and more realistic models, and pay more attention to the empirical issues (as indeed they are beginning to do)