Clause and effect: a Commerce Clause case may limit Congress's power.

• Author: Gillespie, Nick

Gun-ownership cases usually revolve around Second Amendment issues. But United States v. Lopez, currently under consideration by the Supreme Court, involves the 10th Amendment and the Constitution's Commerce Clause. Because Lopez may strongly limit Congress's ability to invoke its right to regulate interstate commerce, the decision may be one of the most far reaching in the post-New Deal era.

In 1992, Alfonso Lopez Jr., a 12th grader at Edison High School in San Antonio, Texas, broke the law by bringing a .38-caliber handgun to school. Although his action was illegal under Texas law, authorities charged Lopez with violating the federal Gun-Free School Zones Act of 1990. Lopez was convicted but appealed the decision on the grounds that the Gun-Free School Zones Act was unconstitutional.

Lopez's lawyers argued that the act invoked no delegated power of Congress for its authority. The government countered that the act was a legitimate exercise of Congress's constitutional power to regulate interstate commerce. The Fifth Circuit Court of Appeals ruled that the statute was outside the commerce power of Congress and an infringement of the 10th Amendment. The court also concluded that Congress could regulate intrastate activity only when it had a "substantial economic effect on interstate commerce."

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