On September 29, 1969, Groppi organized and led the "Welfare Mothers' March on Madison," during which over 1,000 welfare mothers marched into Wisconsin's State Assembly chamber, seizing it in protest against planned welfare cuts.Dennis McCann. "Groppi led Assembly takeover to protest welfare cuts in '69". Milwaukee Journal Sentinel, September 22, 1998. | Groppi and his supporters held the State Assembly chamber in a sitdown strike for 11 hours before police recovered the chamber. Cited in a bill of attainder for "contempt of the State Assembly" and sentenced to six months in jail, Groppi appealed to the federal courts, which quickly reversed his conviction. His last appeal was to the U.S. Supreme Court, which in Groppi v. Leslie invalidated the contempt citation on notice and due process grounds.GROPPI v. LESLIE, 404 U.S. 496 (1972)
