Supreme Court of Justice of the Nation
Introduction
The Supreme Court of Justice of the Nation (Suprema Corte de Justicia de la Nación, SCJN) is the highest constitutional court in Mexico, serving as the final arbiter of constitutional disputes, the guardian of fundamental rights, and the head of the federal judiciary. The SCJN is composed of 11 ministers (reduced to 9 under the 2024 judicial reform), who served 15-year terms prior to the reform mandating popular election.
Composition and Selection
Prior to the 2024 reform, SCJN ministers were appointed by the President and confirmed by a two-thirds Senate vote, serving 15-year non-renewable terms. The 2024 judicial reform replaced this appointment system with popular election, requiring candidates to meet qualification requirements and campaign for judicial office. The reform also reduced the number of ministers from 11 to 9.
Powers and Jurisdiction
The SCJN exercises: original jurisdiction over constitutional controversies between governmental entities; exclusive jurisdiction over actions of unconstitutionality challenging laws and treaties; appellate jurisdiction over amparo cases of constitutional importance; and jurisdiction over the review of electoral laws. The Court also resolves jurisdictional conflicts between federal courts and between federal and state authorities.
Operation
The SCJN operates in a Plenary Session (all ministers) and two chambers: the First Chamber (civil and criminal matters) and the Second Chamber (administrative and labor matters). The Plenary hears the most important constitutional cases, while chambers handle amparo appeals and other matters. Decisions in actions of unconstitutionality require an eight-vote majority (six votes under the reformed Court).
Jurisprudencia
The SCJN establishes binding precedent (jurisprudencia) through: the consistent resolution of cases (five consecutive decisions on the same point); precedent-setting decisions in amparo cases; and the interpretation of constitutional provisions. Jurisprudencia is binding on all lower courts and may be issued by the Plenary or the chambers.
The 2024 Reform
The 2024 judicial reform transformed the SCJN’s composition and selection process. Popular election replaced presidential appointment and Senate confirmation. The reduction from 11 to 9 ministers and the elimination of the CJF’s role in judicial appointments were among the most significant changes. The reform has generated debate regarding judicial independence and political influence.
Conclusion
The SCJN plays a central role in Mexican constitutional law as the final interpreter of the Constitution and the guardian of fundamental rights. Its composition, powers, and jurisprudence have shaped the development of Mexican constitutionalism, and the 2024 reform represents a significant transformation in its institutional design.