This article, which was published in 1985, describes the development of a "Post-Chicago" antitrust policy. The Chicago School of antitrust analysis has made an important and lasting contribution to antitrust policy. The School has placed an emphasis on economic analysis in antitrust jurisprudence that will likely never disappear. At the same time, however, the Chicago School's approach to antitrust is defective for two important reasons. First of all, the notion that public policymaking should be guided exclusively by a notion of efficiency based on the neoclassical market efficiency model is naive. That notion both overstates the ability of the policymaker to apply such a model to real world affairs and understates the complexity of the process by which the policymaker must select among competing policy values.
Second, the neoclassical market efficiency model is itself too simple to account for or to predict business firm behavior in the real world The model has proved to be particularly unsuccessful at identifying many forms of strategic behavior. In large part this is so because the market efficiency model is static and dwells too much on long-run effects. In the real world, short-run considerations are critical to business planning. Furthermore, the short run can be a very long time. In many industries a monopoly that lasts only for the short run can inflict great economic loss on society. By ignoring the short run, the market efficiency model fails to appreciate the social cost of many forms of monopolistic behavior.
Hovenkamp, Herbert J., "Antitrust Policy After Chicago" (1985). Faculty Scholarship. 1924.