Which case established the "aggregate effects" doctrine allowing broad federal regulation of interstate commerce?

• A. United States v. Lopez (1995)
• B. Heart of Atlanta Motel v. United States (1964)
• C. Wickard v. Filburn (1942)
• D. Brown v. Board of Education (1954)

Answer: (C)

Regulatory power under the Commerce Clause can reach local activity if that activity, in the aggregate with similar conduct, substantially affects interstate commerce. Wickard v. Filburn (1942) is the case that embodies this idea. In it, the Court held that a farmer growing wheat for home use could be regulated even though the wheat never entered interstate markets, because many farmers did similar things and the total amount could influence wheat prices and demand in interstate commerce. The decision established the principle that the federal government can regulate indirect effects on the national market by looking at the overall impact rather than a single, isolated instance.

That’s why this case is the best answer: it explicitly articulates the aggregate effects doctrine that broadens federal regulation of interstate commerce. By contrast, United States v. Lopez later limited Congress’s reach by demanding a substantial economic effect from specific conduct for non-economic activities, Heart of Atlanta Motel v. United States upheld regulation under the Commerce Clause in a civil rights context but didn’t hinge on aggregation of similar local acts, and Brown v. Board of Education deals with equal protection, not commerce.