1.  The Supreme Court of Justice of the Nation is the highest court in the land, functioning as the constitutional court of Mexico. The first Constitution of independent Mexico, of 1824, provided for the creation of a Supreme Court, following to some extent the model of the US Constitution. However, it was not until the Constitution of 1857 that the Supreme Court of Mexico started to function with some measure of stability. Jaime Cárdenas Gracia has described the different stages in the evolution of Mexico’s Supreme Court in the following way (Cárdenas 173):

1. 1.  Stage of Definition of the Basic Characteristics of the System (1824–1882)

   In this stage, Mexico’s judicial system was shaped with influence of the US model, but also of the Spanish and French traditions, which led to centralization.

2. 2.  Stage of Subordination to a Non-Democratic and Personalized Regime (1882–1917)

   During these years, the notion that the Supreme Court does not hear electoral-political disputes was consolidated. Moreover, in this stage the Supreme Court did not effectively limit presidential power, though it was able to protect at least some rights of no political content.

3. 3.  Stage of Relative Independence (1917–1928)

   After the military stage of the Mexican Revolution (1910–1917), the Constitution of 1917 established the basis for judicial independence of the Supreme Court, with rules on judicial tenure.

4. 4.  Stage of Subordination to a Non-Democratic and Institutionalized Regime (1928–1944)

   In the phase of formation of the hegemonic party system created after the Mexican Revolution, judicial independence was severely restrained. A constitutional reform of 1934 removed tenure of Supreme Court Justices, who would be in office for a term of six years (just like the President of the Republic).

5. 5.  Stage of ‘Alleviation’ of Backlog (1944–1986)

   Judicial tenure of Supreme Court Justices was re-established with a constitutional reform of 1944. The main concern at this stage was to solve the problem of backlog created with the expansion of the Supreme Court’s jurisdiction.

6. 6.  Stage of Gradual Recovery of Autonomy (since 1986)

   This period coincides with Mexico’s gradual transition to democracy, and is characterized by the strengthening of the Supreme Court’s independence and powers as a constitutional tribunal, and by the professionalization of the federal judicial power.

2.  Finally, we have to add that in 1994 there was an important reform to the structure and competences of the Supreme Court of Justice, which according to some experts, such as Andrea Pozas Loyo and Julio Ríos Figueroa, produced a more independent court (Pozas and Ríos 21). This structure and the competences of Mexico’s Supreme Court will be described in the following section.

3.  The year 1994 was crucial in the institutional development of Mexico’s Supreme Court. In this year, President Ernesto Zedillo introduced an ambitious constitutional reform package that sought to strengthen the Supreme Court as a constitutional tribunal, in its functions as the ‘guardian’ of the Constitution. It was a year of presidential elections, and demands for reforming an inefficient justice system were rampant during the corresponding electoral campaign. Moreover, as reported by Fix Fierro, it seems that the neoliberal policies implemented by Mexican governments since the mid-1980s (which were likely to be implemented by president Zedillo during the 1990s) required an additional element that in those years was still missing: rule of law and, as a consequence, an efficient justice system.

4.  With the constitutional reform of 1994, the number of justices of the Supreme Court was reduced from twenty-six to eleven. The reform sought to create a more compact entity that would be specialized in hearing disputes in which matters of constitutionality were involved. Moreover, the number of chambers was reduced from five to two. In this way, today the first chamber hears cases of civil and criminal law; while the second chamber hears administrative and labour disputes (using those chambers’ ‘power of attraction’ of direct amparos (see writ of amparo) that in principle are heard by collegial circuit courts).

5.  Since 1994, justices of the Supreme Court of Mexico are appointed for a period of 15 years, and cannot be re-appointed (selection of judges at constitutional courts / supreme courts). The system of designation can be summarized as follows: a) the President of the Republic proposes a three name list for each vacancy; b) the Senate can ratify the proposal with a two-thirds majority vote; c) if the Senate does not decide in favour of one of the candidates within 30 days after the proposal of the executive, the latter has the power to pick up the name of the person he deems convenient to fill the vacancy. The same would happen if the Senate rejects in its entirety the three name list proposed by the president on two consecutive occasions, Art. 96 of the Constitution (Political Constitution of the United Mexican States: 5 February 1917 (as Amended to 29 July 2010) (Mex); in the following: ‘the Constitution’).

6.  It is important to notice that before the 1994 reform, justices of the Supreme Court were in charge of the administration of the federal judiciary through a ‘Commission of Administration’. This changed with said reform, with the creation of the ‘Council of the Judicature’, an organ whose function is to administer all matters related to designations, promotions, discipline, licenses, training, and continuing legal education of all the public servants that work in the federal judiciary (including magistrates of circuit and district judges). The goal of this reform was to discharge the justices of the Supreme Court from doing administrative work, so that they could concentrate on their substantive tasks, that is, on judicial-constitutional decision making. Today, the Council of the Judicature has seven members. One of them is the Justice-President of the Supreme Court (who presides over the Council); three members from the magistrates of circuit and district judges, appointed by at least eight votes of the Supreme Court justices themselves; two members designated by the Senate and one by the President of the Republic (Art. 99 of the Constitution).

7.  The Supreme Court was strengthened as a constitutional tribunal, in connection with its jurisdiction to hear disputes between branches of the federal or state governments, and between the different levels of government of Mexico’s federal system. This happened by modifying an action called ‘constitutional controversies’, and by creating a new mechanism called ‘action of unconstitutionality’.

8.  Indeed, the mechanism known as constitutional controversies, established in Art. 105 of the Constitution was modified. Originally, this article granted the Supreme Court the power to ‘hear cases of controversies between two States, between the branches of government of one State on the constitutionality of their acts, and between the Federation and one or more States, as well as those in which the Federation is a party’ (judicial systems in federal systems). Nevertheless, this provision was limited in scope since it did not include all possible conflicts between the different levels of government of Mexico’s federal system. For example, the hypothesis of a dispute in which municipalities or the Federal District were involved was not included in the original text of Art. 105. The reform of 1994 broadened the scope of Art. 105, by including all sorts of conflicts of competence that may arise between branches of the federal government, and between the different levels of government of Mexico’s federal system.

9.  Moreover, the reform of 1994 introduced into the Constitution (Art. 105.II) a new procedure to challenge the unconstitutionality of statutes or treaties: the action of unconstitutionality, which is an abstract mechanism for controlling the constitutionality of norms (it is abstract because it does not arise from a concrete case of application of the challenged statute or treaty). Through this action, the Supreme Court can hear cases that seek to make a statute or treaty null and void if brought by any one of the following: a) at least 33 per cent of the members of the Chamber of Deputies in the case of federal statute laws passed by the Congress of the Union; b) at least 33 per cent of the members of the Senate in the case of federal statute laws or international treaties; c) the President of the Republic, through his legal counsellor, against federal or state ‘general norms’ (this term includes statutes and rulings).

10.  Originally, Art. 105.II expressly established that the action of unconstitutionality could not be used to challenge electoral statutes. Nevertheless, in 1996 this provision was modified to allow this possibility. In addition, Art. 105.II was amended again on 10 June 2011, in order to grant to the National Commission of Human Rights the power to bring the action of unconstitutionality against federal, state, federal district statutes, and international treaties that violate any of the human rights foreseen in Mexico’s Constitution or international treaties on human rights signed by Mexico. This power was also granted to Mexico’s National Human Rights Commission and to the Mexico City Human Rights Commission, to challenge state and Mexico City’s statutes that violate human rights.

11.  With the reform of 7 February 2014, Art. 105.II of Mexico’s Constitution was amended again, to grant the National Institute on Access to Public Information the possibility of filing the action of unconstitutionality against statutes that violate the constitutional right to access to information and the right to personal data protection. The same power was granted to state and federal district’s agencies of transparency, to challenge state and federal district statutes that violate these two rights.

12.  Finally, Art. 105.II was reformed once more on 10 February 2014, to allow the recently created ‘Fiscalía General de la República’ (which is the federal institution that performs the functions of attorney general, with constitutional autonomy) to file the action of unconstitutionality against federal or state statutes it deems are contrary to the Constitution, in matters related to criminal law and criminal procedure.

13.  In ‘constitutional controversies’ and the action of unconstitutionality, a minimum of eight justices must concur in a decision declaring the unconstitutionality of a norm, in order to produce the invalidity of the challenged norm with general effects (erga omnes). This rule is the result of seeking to strike a balance between the old tradition of having inter partes effects of Supreme Court decisions in amparo and the necessity to allow the Court, at least in some cases, to issue general declarations of unconstitutionality, thus invalidating the challenged norm.

14.  Apart from these mechanisms of constitutional justice, the Supreme Court of Mexico has traditionally heard different kinds of disputes, working either in plenary sessions or in chambers. Sitting in plenary sessions, the Supreme Court of Justice has the power to hear, among other cases and disputes: appeals against decisions of district judges or unitary circuit courts rendered in amparo proceedings in which the constitutionality of a federal, state, or Mexico City’s statute or an international treaty was challenged for being contrary to the Constitution; appeals against decisions of district judges or unitary circuit courts that in principle correspond to collegiate circuit courts, when the Supreme Court decides to exercise its power of attraction, in cases of national ‘interest and transcendence’; appeals against decisions rendered by collegiate circuit courts in ‘judicial amparo’ proceedings, in which a matter of unconstitutionality is involved, concerning federal, state or, federal district statute, or of an international treaty; cases in which a public servant does not comply with a judgment in amparo (with the potential of removing that public servant from his position and turn him over to the corresponding district judge in criminal matters); cases of contradiction of criteria held by the first and the second chambers of the Supreme Court; cases in which it is possible to issue a general declaration of unconstitutionality of a norm, according to the procedure established in Art. 107.II of the Constitution; and on the constitutionality of a popular consultation, in terms of Art. 35.VIII of Mexico’s Constitution.

15.  For their part, the two chambers of the Supreme Court of Justice have the power to hear, among other cases and disputes: appeals against judgments rendered by district judges in ordinary federal cases; appeals against judgments courts rendered in amparo proceedings in which the constitutionality of a federal, state or federal district administrative ruling was challenged for being contrary to the Constitution; appeals against decisions of district judges or unitary circuit courts that in principle correspond to collegiate circuit courts, when the corresponding chamber decides to exercise its power of attraction, in cases of national ‘interest and transcendence’; appeals against judgments rendered by collegiate circuit courts in a ‘judicial amparo’ proceeding, when an administrative ruling was challenged for being contrary to the Constitution; judicial or direct amparo’ cases that in principle correspond to collegiate circuit courts, when the corresponding chamber decides to exercise its power of attraction, in cases of national ‘interest and transcendence’, and controversies of competence between federal courts; between federal and state courts; or between the courts of two states.

16.  The first case in which the Supreme Court of Mexico showed its will to be independent from the federal executive occurred in connection with the Constitutional Controversy (26/99), brought by the chamber of deputies against the refusal of the President of the Republic to disclose information that was required by an accountancy firm hired by that chamber to conduct an audit to the so called Banking Fund for the Protection of Savings. With this fund, the federal government helped all the banks that were in trouble because of the financial crisis of December 1994. In essence, this fund was a public trust, which took on the performing loans of banks that were in risk of insolvency when a massive number of people and companies were unable to pay as a consequence of skyrocketing increase in interest rates. But the consequence of this ‘rescue’ was a public debt of 552 billion pesos. This was the reason why the chamber of deputies decided to order an audit to investigate the fund’s operations.

17.  However, the President of the Republic, the Ministry of Finance and other financial regulatory agencies refused to disclose the required information, whereupon the chamber of deputies filed a constitutional controversy, alleging that the constitutional legality principle had been violated because defendants had contradicted a series of rules established in different statutes, which imposed on them the duty to disclose the information that was requested by the chamber of deputies.

18.  The Supreme Court decided by unanimity of the eleven justices in favour of plaintiff. In the Court’s view, the chamber of deputies had ‘the widest powers’ to review the public account of the federal government under Art. 74, s. IV of the federal Constitution including the power to request all the information required to achieve the chamber’s goals; moreover, Congress had the power to ‘recognize and order the payment’ of the national debt, as well as the power to request all the information that is necessary to evaluate whether the recognition of public debt is appropriate or not; finally, the Court reasoned that all secretaries of state have the duty to inform Congress on any matter of their competence, according to Art. 93 of the federal Constitution. For the Court, the president’s refusal to disclose the requested information impeded Congress from exercising its constitutional powers. For that reason, the Court declared that the refusal was unconstitutional and therefore invalid, ordering the President of the Republic to disclose the information (Constitutional Controversy 26/99 (Mex)).

19.  In connection with the writ of amparo, the Acteal case (Direct Amparos 9/2008, 16/2008, 10/2008, 8/2008 Y 33/2008 (Mex)) can be referred to, in which the Supreme Court confirmed its relevance and visibility in Mexico’s constitutional system, as well as its capacity to resist pressure in highly polemic issues. This case involved the killing of forty-five individuals of the Tzotzil indigenous people, in a place called Acteal (state of Chiapas, Mexico), by an armed group. The official version in this case was that the killings had been the result of a dispute between different indigenous people’s communities. Yet, according to some news reports, paramilitary groups that had been formed with the tolerance (if not with the support) of federal and state authorities, were the true perpetrators of the killings.

20.  To calm national and international public opinion’s demands for justice in this case, state and federal authorities hurried up to capture around 100 persons (most of them members of different indigenous communities of Chiapas), accusing them of having perpetrated the killings. Eventually, in 2007, 40 of them were sentenced to 25–40 years of imprisonment. However, they challenged their sentences through the writ of amparo, which in principle has to be brought to the corresponding Collegial Circuit Court. Nevertheless, the first chamber of the Supreme Court exercised its power of attraction and concluded, after examining the case, that fundamental due process rights of the accused had been violated during the criminal trial. For example, the Court found that state and federal authorities had, among other irregularities, concealed evidence, altered the scene of the crime, and fabricated testimonies. Thus, the Court ordered the immediate liberation of 20 of the accused and the replacement of the criminal trial in connection with another six persons (others were equally liberated later on, by further decisions of the first chamber of the Supreme Court).

21.  The action of unconstitutionality 6/1998 was the first in which the Supreme Court decided against the hegemonic political party (that was in power between 1929 and 2000, the so called Partido Revolucionario Institucional or ‘PRI’). This action was filed in 1998 by the leadership of the Partido de la Revolución Democrática (‘PRD’) against a reform to the state electoral code passed by the PRI-dominated legislature and promulgated by the governor (also a member of the PRI), both of the State of Quintana Roo. These two political actors had calculated that they were about to lose the majority of the seats of the state’s legislature in the coming election, so PRI politicians promoted a reform to the state electoral code, seeking to introduce into it the so-called ‘governability clause’, which gave additional seats as a ‘premium’ to the political party that obtained the relative majority in the state legislature, up to the point of letting that party have the absolute majority of the legislature’s seats. In the face of this, the most important argument of plaintiffs in their action of unconstitutionality was that the ‘governability clause’ was not recognized by the federal Constitution as a valid principle of representation to govern the composition of state legislatures (Art. 116.II of the federal Constitution states that state legislatures shall be formed with legislators elected through the principles of plurality and proportional representation).

22.  Eventually, the Supreme Court decided unanimously in favour of plaintiffs. The decision represented a breaking point in Mexico’s constitutional system for two reasons. On the one hand, it affected the fundamental interest of the PRI of keeping control of Quintana Roo’s legislature. On the other hand, with this decision the Supreme Court inaugurated a kind of reasoning based on constitutional values rather than on the letter of the constitutional text. This was so because in its decision the Supreme Court identified in the federal Constitution (specifically in the that refers to the election of deputies to the federal Congress, Art. 54) the constitutional value of political pluralism, and used it as a parameter of control for assessing, and eventually declaring, the unconstitutionality of the ‘governability clause’ contained in a state electoral code (Action of Unconstitutionality 6/98).

23.  In the last 20 years the Supreme Court of Mexico has grown in independence from other branches of government. In addition, through its decisions in constitutional controversies and actions of unconstitutionality, it has been able to draw clearer lines in connection with the ‘vertical’ and ‘horizontal’ scheme of separation of powers in Mexico. Nevertheless, what is pending is the construction of a constitutional doctrine that gives new meaning to fundamental rights. As Magaloni has suggested (Magaloni 279–84), it is possible that the Supreme Court’s ability to consolidate as a protector of human rights in Mexico will require two things. Firstly, a change in the conception of which is the ‘proper’ method of constitutional interpretation when solving cases; and secondly, the ‘strategic’ use of the Court’s ‘power of attraction’. Discussing these two issues, Magaloni has argued that the legalistic and formalistic method of interpreting and applying the Constitution has tended to limit the scope of human rights in Mexico. Moreover, she states that the ‘power of attraction’ of the Supreme Court could be used to select paradigmatic cases in order to develop the content of human rights in a way that could resemble the US Supreme Court with the writ of certiorari.

24.  Another major challenge will come from the international front: the impact of the inter-American system for the protection of human rights may induce Mexico’s Supreme Court to take more decided steps to play a more active and stronger role in this field. In fact, this has already started to happen (see also Inter-American Commission on Human Rights (IACommHR); Inter-American Court of Human Rights (IACtHR)).

25.  As a conclusion, it is possible to say that today, and different from its past experience, the Supreme Court of Justice has become a balancing factor in the political process and in the struggle for the definition of the scope and content of human rights in Mexico. Indeed, the reforms of 1994 contributed to the judicialization of politics, which is proved by the fact that, since then, political actors frequently resort to the Court to solve their disputes. Moreover, the Supreme Court has not hesitated to decide quite controversial cases, declaring, for example, the constitutionality of an amendment to Mexico City’s criminal code that de-criminalized abortion within the first 12 weeks of pregnancy; the constitutional right of transgender persons to modify their officially-recognized sex without having to register their original sex in the corresponding birth certificate (LGBTI rights); the constitutionality of gay marriage allowed by an amendment to the corresponding legislation in Mexico City (same-sex marriage / registered partnership); and the unconstitutionality of five articles of the federal Health Act that banned the cultivation of marijuana for recreational use. However, the construction of a constitutional doctrine that gives new meaning to fundamental rights is still pending. Finally, it is possible to say that rather than being an ‘exporter’ of judicial constitutional doctrine, the Supreme Court of Mexico is a net ‘importer’. This is clear, for example, in the Court’s conception of the circumstances under which a differential treatment to a person does not constitute a violation of the right to no discrimination (ie whenever there are ‘objective and reasonable’ motives that justify that differential treatment, an idea presumably taken from the Constitutional Court of Spain (Tribunal Constitucional de España)). And it is also clear in Mexico’s Supreme Court notion of the right to minimum level of subsistence (mínimo vital), which is a notion developed by the Constitutional Court of Colombia (Corte Constitucional de Colombia) at least since the beginning of the 1990s (this notion refers to the right to enjoy the minimum material conditions that make it possible to live with dignity). The use of comparative constitutional jurisprudence is a positive practice of Mexico’s Supreme Court, and it will most likely play an important role in the development of its own doctrine in the future. However, the Court should recognize and expressly cite its sources, whenever its justices engage in this constructive practice.