When the state acts as a market regulator, the dormant Commerce Clause invalidates discriminatory regulation without the need for an order against the state. The courts simply refuse to enforce the state law on the ground that it is unconstitutional. When the state acts as a market participant, however, the court would have to direct its order against the state or its officials to negate the discrimination. This produces a direct confrontation with the state, the same kind of confrontation the clear statement rule was designed to avoid. Part II of this article examines the theory of the dormant Commerce Clause, and concludes that it is a presumption of congressional intent based on a substantive policy choice to limit discrimination against interstate commerce. Part III looks at the justifications offered for the market participant exception, which permits states to discriminate in favor of their own people in state purchases and sales, and suggests that justifications offered by the Court and commentators are conclusory or inadequately explained. Part IV explains the clear statement rule, which is concerned with intrusions into state sovereignty, and shows how that rule applies to the dormant Commerce Clause when the government participates in the market. Part V discusses the exception for downstream regulation of interstate commerce, in which the concern for intrusion into state sovereignty does not apply. Part VI examines other constitutional clauses that may prohibit states from using their power to purchase or sell goods or services in order to discriminate against commerce from other states. This Part concludes that the market participant doctrine, which prevents the federal government from ordering states to make specific purchases or sales without a congressional determination that such regulation is necessary, is a sound application of the clear statement rule that poses no threat to interstate commerce in the light of other safeguards.
David S. Bogen, The Market Participant Doctrine and the Clear Statement Rule, 29 SEATTLE U. L. REV. 543 (2006).