The appointment of former politicians to constitutional courts is a global phenomenon. While ex-politician appointees may bring status, visibility, knowledge, and political awareness to the job, their previous roles may influence their assessment of legislations' constitutionality. Ex-Ministers as Constitutional Judges sheds light on this practice in four of the world's oldest and most established constitutional courts: Austria, France, Germany, and Italy. Weaving together legal, political, sociological, and historical sources, including press articles, surveys, and interviews with constitutional judges and high-level personnel, the book provides the first comprehensive exploration of ex-politicians becoming constitutional court judges. It analyses the advantages and disadvantages such personalities bring to constitutional courts, as well as assessing what limitations supranational law may set for such participation. Whereas the participation of ex-ministers does not seem to have posed serious structural issues to constitutional courts so far, this volume posits that the risks have been underestimated. In this context, Ex-Ministers as Constitutional Judges ultimately suggests normative steps for minimizing such risks and strengthening the independence and impartiality of constitutional courts in view of democratic and constitutional backsliding.