He was the defendant/appellee for the federal government of the United States in Buckley v. Valeo, 424 U.S. 1 (1976), in which the Supreme Court of the United States upheld federal limits on and disclosure requirements for campaign contributions but struck down limits on campaign and independent expenditures.
In the landmark case Buckley v. Valeo, 424 U.S. 1 (1976), he served as the defendant/appellee for the US government, arguing that federal regulations on and disclosure of campaign contributions were constitutional, while also challenging limits on campaign and independent spending.