Separation of Powers Under the 1917 Constitution

Introduction

The separation of powers (división de poderes) is a foundational principle of the Mexican constitutional order, established in Article 49 of the Constitution. The federal government is divided into three branches: the Legislative Power (Poder Legislativo), the Executive Power (Poder Ejecutivo), and the Judicial Power (Poder Judicial). The Constitution prohibits the exercise of two powers by a single person or entity, with limited exceptions provided by law.

Legislative Power

The Legislative Power is vested in the Congress of the Union (Congreso de la Unión), a bicameral body composed of the Chamber of Deputies (Cámara de Diputados, 500 members) and the Senate (Cámara de Senadores, 128 members). The Chamber of Deputies represents the people, with members elected every three years through a mixed system of 300 single-member districts and 200 proportional representation seats. The Senate represents the states, with 96 senators elected by direct vote (three per state) and 32 by proportional representation.

Executive Power

The Executive Power is vested in the President of the United Mexican States, who serves a single six-year term without the possibility of re-election. The President is the head of state and government, commander-in-chief of the armed forces, and responsible for executing the laws. The President appoints secretaries of state (ministers), the Attorney General, and senior officials, subject to Senate confirmation in specified cases. The executive is accountable to Congress through the mechanisms of political and criminal liability.

Judicial Power

The Judicial Power is vested in the Supreme Court of Justice of the Nation (SCJN), the Federal Judiciary Council (CJF), the Electoral Tribunal (TEPJF), circuit courts, and district courts. The judiciary is independent and exercises constitutional review through amparo, actions of unconstitutionality, and constitutional controversies. The 2024 judicial reform introduced popular election of judges, altering the traditional appointment process while maintaining the judiciary as an independent branch.

Checks and Balances

The Constitution establishes mechanisms for inter-branch checks and balances: Congress may approve or reject presidential appointments, ratify treaties, approve the federal budget, and impeach senior officials. The President may veto legislation (subject to a two-thirds congressional override), issue regulatory decrees, and propose legislation. The judiciary may declare laws unconstitutional through abstract review (action of unconstitutionality) or concrete review (amparo).

Conclusion

The separation of powers is a structural principle of the Mexican Constitution, designed to prevent authoritarianism and ensure governmental accountability. While the presidential system concentrates significant power in the executive, the legislative and judicial branches exercise countervailing authorities that maintain constitutional equilibrium.