Mexican constitutionalism after presidencialismo
* Leonard B. Rosenberg Professor of Law, University of Houston Law Center. Email: SZamora{at}UH.edu
** Justice, Mexican Supreme Court, professor of constitutional law and former dean, Instituto Tecnológico Autónomo de México (ITAM). The authors are indebted to Ran Hirschl and Christopher Eisgruber for their valuable suggestions; to Monica Castillejos for her research and editing assistance; and to Rocio Alonso Garibay for her research assistance. All translations of Spanish-language texts quoted in this essay are by the authors.
This article discusses the fundamental changes that have occurred during the past decade in institutions central to Mexico's constitutional order. The demise of a single-party democracy not only created a new political order; it generated, as well, fundamental changes in Mexican constitutionalism, with formal constitutional and legal reforms playing an important but secondary role in revising Mexico's constitutional structure. The authoritarian presidencialismo that dominated Mexico's political culture throughout much of the twentieth century has been replaced by a disempowered presidency and a divided Congress, with a revamped Mexican Supreme Court—long a minor factor in Mexican constitutional politics—assuming a key role in the development of the law. In discussing these changes, the article focuses on three primary areas of the new constitutionalism: separation of powers and the new role of the Mexican Congress; the new role of the Mexican Supreme Court as arbiter between Congress and the presidency; and changes in Mexican federalism. The political instability of multiparty politics in Mexico will place further strains on Mexican constitutionalism in the future and will require careful responses from those institutions—especially the Supreme Court—that oversee the development of law in Mexico.