During the end of 2020 and the beginning of 2021 Sébastien Nadot supported the cause of Catalan parliamentarians imprisoned in Spain. He has defended their right to exerce their European parliamentary mandate, as their parliamentary immunity was lifted. He asked French European and Foreign Affairs Minister Jean-Yves Le Drian about this matter to which the Minister replied by affirming his support to the Spanish rule of law and to the European Parliament's power to lift the immunity.