Abstract : The EU has brought about new constraints and new prerogatives for national parliaments1. Some procedures and structures have been created in order to cope with the loss of control of national parliaments over the European legislative process (O'Brennan, Raunio, 2007; Tans, Zoethout, Peters, 2007; Costa, Rozenberg, 2008). All over Europe, national chambers have notably created EU committees in charge of sifting through and of scrutinising community projects on legislation and on the monitoring of their government's European policy (...).