Major Differences Between the Mexican and U.S. Legal Systems

As many attorneys already know, the Mexican and U.S. legal systems have a number of differences. The U.S. legal system is a common law system, growing from the English legal tradition. This means that, in the United States, published and collected judicial opinions are considered binding legal authority. In the Mexican civil law system, on the other hand, codified law is of primary importance.

Though the systems are different, there are also many similarities that attorneys will recognize from one country to the other. Below, we’ll contrast and compare the systems with the goal of helping Mexican attorneys better understand them, as well as the role of practitioners in each system.

Although the United States is a common law jurisdiction, statutes, codes and regulations still exist at the federal, state and local levels. Published judicial opinions are not the sole source of authority in the United States. In fact, litigation often centers on codified law. This may be somewhat familiar to Mexican attorneys, who will look first to codes, but who may also do research on doctrina (scholarly treatises), or even jurisprudencia (decisions of high courts) in order to fully prepare for client representation on a particular matter.

In the U.S. educational system, students only pursue legal degrees after first obtaining a four-year undergraduate degree (bachelor’s degree) in any non-legal topic of their choosing from a college or university. Afterward, they attend three-year programs at law schools in order to obtain a Juris Doctor (J.D.) degree. Once they have graduated, they then sit for the bar exam in a particular state and obtain a license to practice law.

In contrast, a Mexican attorney can obtain a law degree (a Licenciatura En Derecho, or LED) after a five-year undergraduate program, and does not need to take a bar exam afterward in order to become licensed to practice law. Instead, upon registering as an LED graduate, a Mexican attorney may then become a licensed legal practitioner.

In Mexico, a judge leads and regulates the course of litigation, investigating facts, examining witnesses and appointing experts. In the United States, on the other hand, attorneys for the plaintiff or defendant may handle these tasks. Indeed, facts are learned through an attorney-led process called “discovery,” in which the attorneys for the plaintiff and defendant ask questions and request materials from one another — this process is overseen, however, by a judge. Mexican attorneys still counsel clients on matters related to the litigation, of course, and will also prepare pleadings and related documents. In addition, in the U.S., there may also be a jury (a panel of 6-12 citizens, chosen at random) present in a U.S. legal trial to determine facts and make ultimate judgments in the case. Mexican proceedings do not follow this tradition.

Both legal systems have state and federal courts, as well as special niche courts that handle specific issues (tax courts, bankruptcy courts, etc.) However, the U.S. has a smaller variety of administrative courts when compared to Mexico. For example, Mexico has the Tribunal de Justicia Agraria for agrarian matters, and the Tribunal de Jurisdiccion de Proceso Electoral for matters pertaining to the electoral process, while the U.S. has no analogous courts. Instead, in the U.S., many such matters are left to be initiated in the Federal District Courts.

In general, the primary role of the attorney in court proceedings and the importance of case law are the main differences for Mexican attorneys to understand about the U.S. legal system. Those interested in learning more about the details of U.S. law, or who are considering expanding their practices internationally, might want to consider the @WashULaw LL.M. in U.S. law program or the dual LL.M. in U.S. Law and Transnational Legal Practice with Tecnológico de Monterrey’s EGAP School of Government.