32 senators and to the election of the President of the Republic], that violate constitutional or legal norms.” […] c) Acts and decisions that violate the political and electoral rights of the citizens to vote and to be elected in the general elections, to associate individually and freely to take part peacefully in political matters, and to join political parties individually and freely, provided the constitutional requirements have been met together with those indicated in the laws for their exercise. 121. Without detriment to the fact that the Constitution and the Law on the Judiciary grant competence to the Electoral Tribunal to review “contestations of acts and decisions that violate political and electoral rights,” Article 105, subparagraph II, of the Constitution, which regulates the exclusive competence of the Supreme Court of Justice to hear judicial proceedings on unconstitutionality, has established, since 1996, that the “only means for alleging the non-conformity of the electoral laws with the Constitution is the one provided for in [the said] Article.”36 122. In keeping with Article 105(II) of the Constitution, Article 10 of the Law on Contesting Electoral Matters provided that the contestation mechanisms, including the judicial action to protect the political and electoral rights of the citizen, “shall be inadmissible […w]hen the intention is to contest the unconstitutionality of federal or local laws.” 36 Article 105. The Supreme Court of Justice shall hear, in the terms established in the law regulating it, the following: […] II. Unconstitutionality proceedings with the purpose of raising possible contradictions between a general norm and this Constitution. Unconstitutionality proceedings may be filed within the 30 calendar days following the publication of the norm, by: (a) The equivalent of 33% of the members of the Chamber of Deputies of the Congress of the Union, against federal laws or laws of the Federal District issued by the Congress of the Union; (b) The equivalent of 33% of the members of the Senate, against federal laws or laws of the Federal District issued by the Congress of the Union, or international treaties concluded by the Mexican State; (c) the Prosecutor General (Procurador General), against federal, state and Federal District laws, and international treaties concluded by the Mexican State; (d) The equivalent of 33% of the members of a state legislative organ against laws issued by that organ; (e) The equivalent of 33% of the members of the Assembly of Representatives of the Federal District, against laws issued by the Assembly; and (f) The political parties registered with the Federal Electoral Institute, through their national leadership, against federal or local electoral laws; and the political parties registered with the states, through their leadership, exclusively against electoral laws issued by the legislative organ of the state where they are registered. The only means of contesting the conformity of the electoral laws with the Constitution is established in this Article. Federal and local electoral laws shall be promulgated and published at least 90 days before the start of the electoral process in which they will be applied and, during this process, no fundamental modifications shall be made to the laws. The decisions of the Supreme Court of Justice may only declare the invalidity of the contested norms if they are adopted by a majority of at least eight votes.