21. Should the court grant the injunction?

Article I, Section 8, Clause 3 empowers Congress to «regulate commerce with foreign nations and among the several states, and with the Indian tribes.» Commerce is defined as «every species of commercial intercourse. .. which concerns more states than one» and including virtually every form of activity involving or affecting two or more states. Gibbons v. Ogden, 22 U.S. 1 (1824). To be within Congress's power under the Commerce Clause, a federal law must regulate under one of four categories: (i) channels of interstate commerce; (ii) instrumentalities of interstate commerce and persons and things in interstate commerce; (iii) articles moving in interstate commerce; or (iv) activities that have a substantial effect on interstate commerce.

If the regulated intrastate activity is not commercial or economic, the Court generally will not aggregate the effects and the regulation will be upheld only if Congress can show a direct substantial economic effect on interstate commerce, which it generally will not be able to do. See, e.g., United States v. Lopez, 514 U.S. 549 (1995). However, the Court has consistently regarded transportation or traffic as commerce, whether or not a commercial activity is involved.

The Tenth Amendment provides that all powers not delegated to the federal government by the Constitution are reserved to the states (or to the people). However, given the expansive interpretation of federal powers (e.g., the commerce power), little state power is exclusive. The Supreme Court has held that the Tenth Amendment prohibits Congress from adopting a statute that «commandeers» state officials by requiring states to regulate their own citizens. Printz v. United States, 521 U.S. 898 (1997).

A is correct. The court should not grant the injunction because the statute falls within the powers attributed to Congress through Commerce Clause; it regulates a commercial activity (the purchase of cars) that, when aggregated, has a substantial effect on interstate commerce. The statute does not violate the Tenth Amendment as applied to the city because it does not commandeer the city to regulate the conduct of others pursuant to congressional direction. Instead, it directly regulates the city on the same terms as other entities engaged in the same conduct, which is permissible under the Tenth Amendment.

B is incorrect. This answer reaches the correct answer with the wrong reasoning. Although it is true that the court should not grant the injunction, it is not because the federal government enjoys sovereign immunity in this case. The prohibition against suing the federal government without its consent only applies to cases involving compensatory monetary relief, not actions involving prospective injunctive relief, as is the case here. The basis for denying the injunction is that the statute falls within congressional commerce powers and does not run afoul of the Tenth Amendment, as explained above.

C is incorrect. The statute does not violate the Tenth Amendment because it does not commandeer the city's regulation of the conduct of others pursuant to congressional direction. Instead, it directly regulates the city's conduct on the same terms as other entities engaged in the same conduct, which is permissible under the Tenth Amendment. The statute satisfies the Commerce Clause because it regulates a commercial activity (the purchase of cars) that, when aggregated, has a substantial effect on interstate commerce.

D is incorrect. This statute is valid under the Commerce Clause, as stated above. The Commerce Clause allows Congress to constitutionally regulate under the commerce power, which extends to channels of interstate commerce, instrumentalities of interstate commerce, articles moving in interstate commerce, and activities having a substantial effect on interstate commerce. Here, the activity of owning 100 cars would substantially affect interstate commerce regardless of whether it is a purely intrastate activity.