Since the enactment of Superfund in 1980, critics of the statute's liability regime have been relentless in their attempts to convince courts that Superfund liability is so unfair as to be unconstitutional. While their persistence has produced only minor changes in the liability regime, their cause may have been given a lift by the U.S. Supreme Court's 1998 decision in Eastern Enterprises v. Apfel. In that decision, the Court held that when a statute "imposes severe retroactive liability on a limited class of parties that could not have anticipated the liability," and the liability is "substantially disproportionate to the parties' experience," the legislation is unconstitutional. Those words have sparked the critics' hopes that the Court will eventually conclude that Superfund is just such a statute.

The long-running war over Superfund liability has been like the early stages of a bullfight. The statutory liability regime is the bull, striking fear into the hearts of businesses like no other regulatory statute has before or since. Superfund's critics have played the role of the picaderos and banderillos, striking out at the bull in the courts and the U.S. Congress, landing only nonlethal blows and narrowing the reach of the Superfund liability regime only at the margins. Will Eastern Enterprises prove to be the final act of this drama, or just another flesh wound? Many view this latest argument as merely another in a long line of meritless constitutional challenges, all of which are doomed to fail. After all, the courts have rejected similar claims before; nor, say the statute's defenders, should we read much into the Eastern Enterprises decision, a case in which the Court could not even cobble together a majority opinion. Furthermore, they contend, to the extent that there is an Eastern Enterprises test of the constitutionality of retroactive legislation, Superfund passes that test: unlike the statute at issue in Eastern Enterprises, Superfund is remedial, designed merely to make the polluter pay. I argue here that the effect of Eastern Enterprises may be more significant than that.