Citizenship and free movement: European and American features of a judicial formula for increased comity

This article explores the judicial application of the doctrines of free movement/right to travel and citizenship in the European Union and in the United States. A comparative examination of the case law on these two doctrines shows remarkable similarities in the European and American courts’ combination of citizenship and free movement in resolving analogous judicial issues. Further investigation, however, reveals that behind a first sight affinity of judicial formulas, different rationales and diverging constitutional roots can be found in the two systems. In particular, the article explores the regime of free movement of students and professionals in the two systems and highlights some unexpected differences. Considerations of economic versus political integration and interstate equality versus state autonomy turn out to be key in identifying the centripetal forces that govern the role of citizenship in the two examined systems.