The Dormant Commerce Clause as an Ex Ante Rule

Abstract

Like other anti-discrimination rules, the dormant Commerce Clause principle is supported by second-order principles to control against over-inclusiveness on one side and evasion on the other. First, the rule permits discriminatory state laws when no non-discriminatory means are available to protect a legitimate state interest. One can understand this exception in analogy to the "operational necessity" defense in equal protection law, which permits the racial segregation of prison inmates or the race-conscious selection of personnel in penal institutions, for obvious and compelling reasons. Second, the anti-discrimination principle is buttressed by "anti-sham" rules to protect against brazen evasions of the core principle. The most important of these rules is the bar against state laws that discriminate in purpose or effect. The "balancing" test of Pike v. Bruce Church fame and the "combined effects" doctrine of West Lynn Creamery v. Healy serve the same anti-circumvention purpose. To be sure, some Supreme Court opinions seem to describe those analyses as separate rather than ancillary tests, and the dormant Commerce Clause does not apply to all forms of discrimination. But those sorts of questions arise under (and over) all anti-discrimination principles, such as the Equal Protection Clause or the Privileges and Immunities Clause.

So understood, the dormant Commerce Clause is preferable, ex ante, to the following alternatives: (1) no constitutional, judicially enforceable Commerce Clause limitations on state regulation at all; (2) a generalized judicial balancing test; and (3) more restrictive alternatives, such as an "exclusive" interstate commerce clause (the prevailing understanding for much of the nineteenth century) or an "origin principle" (the European model). I consider these in turn.

Keywords: dormant Commerce Clause, ex ante rule