There exist three types of actions:
First, “Diffuse Actions” protect the indivisible rights of an undefined collective. These actions aim for general reparation rather than individual monetary compensation. They do not require a common legal connection to the defendant or a minimum number of members. Second, “Strict Sense Actions” safeguard the rights of a group comprising at least 30 identified or identifiable individuals. These actions require a common legal bond and permit compensation for individual damages. Third, “Homogeneous Individual Actions” protect the contractual rights of at least 30 individuals with similar claims. These actions require a "common origin" and aim to secure individual indemnities.
Rules for commonality of claims/class certification
In Mexico, class actions require "common elements of fact and law," meaning the cause of the damages must be uniform across the entire class, with any differences among members being secondary. In product liability cases, proving a "design defect" is generally easier than a "manufacturing defect," as the latter pertains to individual products and complicates the commonality argument. A strict interpretation of this requirement can undermine procedural efficiency and potentially render litigation unfeasible.
After the complaint is filed, the judge orders service of process on the defendant, granting them five days to present arguments opposing class action certification. The judge then evaluates several key requirements, including whether the acts impact consumers or the environment, the presence of commonality, the existence of at least 30 class members (depending on the type of class action), adherence to the statute of limitations, and whether the matter is free from res judicata, among other factors.
Class member participation (opt-in/opt-out)
Mexico has an “opt-in” model, requiring the express consent of collective members to participate. For Strict Sense and Homogeneous Individual actions, at least 30 members must join to initiate the process. This active membership requirement, which obligates plaintiffs to identify and document class members, poses a significant logistical challenge. Unlike the “opt-out” model, which automatically includes all potential claimants, the opt-in approach restricts the size of mass claims and may deter large-scale litigation.
A judgment in a class action is appealable, and its enforcement is suspended until the Court of Appeals issues a decision. This can substantially extend the duration of the judicial process. Additionally, aggrieved parties may challenge the appellate judgment by filing a constitutional claim (“amparo”).
Third-party litigation funding is gaining traction in Mexico as a means to offset high litigation costs. The absence of specific regulations governing this practice offers significant flexibility.