For almost fifty years, scholars have urged the Court to "balance" in dormant commerce clause cases; and the scholars have imagined that the Court was following their advice. The Court has indeed claimed to balance, winning scholarly approval. But the Court knows better than the scholars. Despite what the Court has said, it has not been balancing. It has been following a simpler and better-justified course. In the central area of dormant commerce clause jurisprudence, comprising what I shall call "movement-of-goods" cases), the Court has been concerned exclusively with preventing states from engaging in purposeful economic protectionism. Not only is this what the Court has been doing, it is just what the Court should do. This and no more. In cases other than movement-of-goods cases - cases involving regulation of railroads or highways, cases about taxation - the Court has had certain limited goals over and above preventing protectionism. Indeed, in cases dealing specifically with regulation of the transportation system, the Court may even engage in a very particular balancing task. But in no area has the Court engaged in the sort of open-ended balancing the scholars have recommended. In this essay, I shall concentrate on the movement-of-goods area. The claim I am most concerned to establish is my claim that in this area the Court is concerned and should be concerned only with preventing purposeful protectionism. In fact, the discussion in Part III of what the Court is doing will be limited almost entirely to the movement-of-goods area. In Part II, where I discuss what the Court should be doing, it is again the movement-of-goods area that interests me most; but the argument establishing that, in this area, the Court should be concerned only with preventing protectionism will reveal quite naturally why certain other areas involve additional, but always limited and specific, judicial tasks.
Regan, Donald H. "The Supreme Court and State Protectionism: Making Sense of the Dormant Commerce Clause." Mich. L. Rev. 84 (1986): 1091-287.