In 1942, the United States Supreme Court, in Wickard v. Filburn, told a farmer that he couldn't have his wheat and eat it, too. In an attempt to improve the weak economic climate in the wake of the Great Depression, Congress enacted the New Deal. One piece of legislation, the Agricultural Adjustment Act of 1938, imposed a maximum quota on the amount of wheat that farmers could produce. Congress passed the act in response to a nationwide wheat surplus relative to demand. Farmer Filburn, who operated a small dairy farm in Ohio, grew wheat primarily for home consumption and to feed his livestock.
Filburn received a fine after growing more wheat than his allotted quota. He filed a lawsuit against Wickard, the Secretary of Agriculture, seeking to enjoin enforcement of the act. Because Filburn wasn't placing his wheat into the stream of interstate commerce, he argued that his wheat production couldn't be controlled by Congress under its Commerce Clause authority. Filburn argued that his activity couldn't be regulated under Congress's commerce power because he wasn't going to sell his wheat, and his wheat wasn't crossing state lines.
The district court agreed with Filburn and found the act, as applied to him, unconstitutional. On direct appeal, The issue before the United States Supreme Court was whether Congress's Commerce Clause authority allows it to regulate purely in-state activities, such as the private cultivation of wheat. The court held that Congress may regulate in-state activities if they have a substantial effect on interstate commerce. Justice Jackson, writing for the unanimous court, reasoned that wheat grown for home consumption can substantially affect interstate commerce. To reach this conclusion, The court applied what's now known as the aggregation doctrine.
The doctrine hypothetically combines all instances of a given activity and then asks whether that activity, considered in the aggregate, would impose a substantial effect on interstate commerce. Here, the court looked not just at Filburn's own wheat production, but the effect on interstate commerce of all wheat grown for home consumption across the nation. The court reasoned that if Congress couldn't regulate small amounts of wheat, then large aggregate amounts of wheat would escape congressional regulation too. The court found that Filburn's activities substantially affected interstate commerce, because if Filburn wasn't growing wheat himself, he would be buying wheat on the open, national market. By imposing a quota on private wheat cultivation, the act effectively forced Filburn to purchase his wheat rather than to grow it himself.
Forcing Filburn and others to purchase wheat increased the demand for wheat on the open market. which was the purpose of the statute. Because the in-state cultivation of wheat, considered in the aggregate, substantially affected interstate commerce, the Supreme Court reversed the district court and held that the act was constitutional as applied to Filburn.
Wickard v. Filburn was a landmark decision that interpreted Congress's Commerce Clause authority to reach purely in-state activities using the aggregation doctrine. Although the decision has been criticized for its broad interpretation of the Commerce Clause, the Supreme Court continues to apply Wickard in its modern jurisprudence.