The UFF's founders came out of prison, not the campuses. Raymond Luc Levasseur, a French-Canadian mill-town Vietnam veteran radicalized by the war and by a Tennessee drug sentence, and Tom Manning, a Boston working-class veteran politicized in Walpole prison, met through SCAR — the Statewide Correctional Alliance for Reform, a Maine ex-prisoner organization running bail funds, a bookstore, and prisoner-support programs in the early 1970s. Around them gathered Carol Saucier Manning, Pat Gros, and the Ohio organizers Jaan Laaman and Barbara Curzi, with Richard Williams and Kazi Toure of the same prison-movement milieu.
Concluding that legal reform work was met only with repression, the group went underground in the mid-1970s as the Sam Melville–Jonathan Jackson Unit — named for the Attica and Marin County martyrs — announcing itself in 1976 by bombing the Suffolk County Courthouse in Boston in protest of prison conditions and the case of Bobby Dellelo.