Aggregate effects doctrine

The Aggregate effects doctrine or Cumulative effects doctrine is a legal doctrine in United States federal law. The AED permits extension of the regulation of interstate commerce into any action which affects interstate commerce only when aggregated with other actions. It is most often associated with Wickard v. Filburn 1942. In Wickard a wheat farmer growing wheat solely for animal feed within the confines of his own farm was found to be regulatable because private growth for private consumption was the primary reason for decrease of demand.

Although mostly associated with Wickard, it is also referred to as "substantial effects" in another formative case the preceding year, U.S. v. Darby Lumber Co., 1941. In the previous term the same idea was the reasoning for the decision of NLRB v. Fainblatt. In Fainblatt the "plenary" power of interstate regulation "extends to all such commerce be it great or small" and had never been held "to be constitutionally restricted because in any particular case the volume of the commerce affected may be small."