Petry has been a member of
Illingen municipal council since 1989; he is also a member of Welschbach local council and has been the leader of the council since 1999. In 2014, Petry became a member of the German Bundestag. He has since been a member of the Committee on European Union Affairs, the Finance Committee and the Parliamentary Panel on Financial-Market Stabilisation. Since 2018, he has been his parliamentary group's spokesman on European affairs. In addition to his committee assignments, Petry is a member of the German-French Working Group on the Élysée Treaty and the Inter-Parliamentary Conference on Stability, Economic Coordination and Governance in the EU. He has been a member of the
Franco-German Parliamentary Assembly since 2019. In 2020, Petry also joined the German delegation to the
Parliamentary Assembly of the Council of Europe (PACE). Within the SPD parliamentary group, Petry belongs to the
Parliamentary Left, a left-wing movement. == Other activities ==