Mexico is a federal republic consisting of a federal government, 31 individual state governments, and a Federal District.
The Federal government is divided into executive, legislative, and judicial branches. Each branch is covered in more detail below.
The hierarchy of sources of law are constitution, legislation, regulation, and custom.
Federal legislation in codified in five major codes: the civil code, the commercial code, the criminal code, the civil procedures code, and the criminal procedures code. Because Mexico’s legal system is based on civil law, the state and federal district civil codes are very similar to the federal civil code.
A civil law legal system is statutorily based, which means cases are decided individually by looking at the law. Unlike in the United States, Mexican case law does not have precedential value. Instead, there is "jurisprudencia," which is only established when the Supreme Court and the federal collegiate courts issue five consecutive and consistent decisions on a point of law. When the law is unclear, judges look to legal treatises call "doctrina" written by legal scholars.
The executive branch carries the most political power. While the Mexican Constitution empowers both the executive and the legislative branches to initiate legislation, in practice the executive branch initiates almost all legislation and certainly all legislation of any consequence. The president is elected to a six-year term with no re-election. The president has the power of the veto, which the legislative branch can override by a two-thirds vote in each Chamber.
The legislative branch of the federal government is comprised of the Senate and the Chamber of Deputies. There are two senators per state and one deputy for every 250,000 people in a state. Senators serve a 6-year term and deputies are elected to a 3-year term. Neither senators nor deputies cannot be re-elected for an immediately succeeding term. Each new bill must pass both Chambers by a majority vote. The legislative branch can override by a two-thirds vote in each Chamber.
The Mexican Federal Judiciary is based on a three-tier system similar to the U.S. federal judiciary.
There are several federal bodies in Mexico that are not part of the regular federal court structure, including the Tax Court (Tribunal Fiscal de la Federacion), Labor Courts (Juntas de Conciliacion y Arbitraje), and Military Courts (Tribunales Miltares).
The Supreme Court is composed of 11 Justices and 1 Chief Justice. The Supreme Court also divides and meets in panels: criminal panel, civil panel, administrative panel, and labor panel.
Federal courts have jurisdiction over controversies that arise out of laws or acts of state or federal authorities that violate individual guaranties; controversies between states or a state and federal authorities; all matters involving federal laws and treaties; all sin which the federal government is a party; all matters involving maritime law; and all cases that involve members of the Diplomatic and Consular Corps.
However, one of the most important type of cases the federal courts hear in Mexico are "amparo" suits (juicio de amparo), which have no exact equivalent of the common law tradition. Legally, the word encompasses element of several legal actions of the common law tradition, specifically, writ of habeas corpus, injunction, error, mandamus, and certiorar.