In the United States, the Seventies are often seen as a decade of distrust towards a government whose legitimacy was being questioned. However, they also paved the way for citizen mobilisations of a progressive nature, aiming at the reform of the State. Activist and whistle-blower Ralph was one of the key figures. At the head of Public Citizen, the interest group he created, he defended an active conception of citizenship whose goal was to obtain the opening, the increased accountability and the democratization of the government, in both its administative and representative dimensions. This article shows how Nader ambitioned to turn citizens into agents of change thanks to monitoring instruments designed by professional lawyers.