1. Is your jurisdiction primarily a common law, civil law, customary law or theocratic law jurisdiction? Are the laws substantially derived from the laws of another jurisdiction and, if so, which? What instruments have legal force and effect? Who are the lawmaking bodies? How and where are new laws published? Can laws be passed with retrospective effect?
The Mexican legal system follows the civil law tradition. Mexico is also a federal system, where both the federal and the state governments have lawmaking power.
At the federal level, only duly-enacted written statutes and decrees, as well as duly-ratified international treaties, are valid and effective in Mexico. Additionally, subject to certain rules, court precedents can be binding. Federal law regulates the areas permitted by article 73 of the Constitution, which include the agrarian sector, national waters, aeronautics, commercial law, labour law, energy, oil and gas, and national security.
Federal statutes are enacted by Congress and decrees are issued by the President of the Republic. Once a congressional statute has been promulgated by the President, they are published in the Official Federal Gazette (Diario Oficial de la Federación). Statutes become effective on the date stated in the publication or three days after publication if no specific date is set.
States have the authority to enact laws regarding all matters not expressly reserved for the federal government including civil and criminal law in their territory.
There are also many areas where federal and state jurisdiction overlap, such as public health.
General principles of private law in Mexico are mostly contained in the Federal Civil Code (FCC) enacted in 1928 and the Commerce Code enacted in 1889. In the context of arbitration, Mexico adopted the UNCITRAL Model Law in 1993 with few amendments. It is contained in articles 1415 to 1480 of the Federal Commerce Code.
In certain limited circumstances, laws in Mexico can be passed with retroactive effects, as long as such effects run to the benefit of individuals. For example, a person who is serving a criminal sentence may be released if the crime of which he or she was found guilty is later abolished. However, in the sphere of private law, retroactivity is very uncommon. The terms of the parties’ relationship are governed by their contract and by the law in force at the time of the agreement, with few mandatory rules being imposed by law.Answer contributed by Pedro José Izquierdo, Sophie A Kivett, Rodrigo Macin Sánchez and Montserrat Manzano
Sullivan & Cromwell LLP and Von Wobeser y Sierra, SC