Theses and Case Law/ Litigation / byDaniel Majewski del Castillo,Guadalupe Villa Figueroa,Raúl Alonso Flores Hernández, and Frida Isabel Velázquez Vargas.
On #ThesisFriday | On October 16, 2026, the Semanario Judicial published 33 new rulings: 13 case law decisions and 20 isolated legal opinions.
We’ve selected the most relevant ones for you, which were issued by the Supreme Court of Justice of the Nation, the Collegiate Circuit Courts, and the Regional Circuit Plenary Sessions:
Abstracts
Digital Registration: 2032761 / Thesis: P./J. 201/2026 (12th)
Case Law of Regional Circuit Courts
The decision on the appeal, which confirms the admission of the direct constitutional appeal for review, constitutes res judicata with respect to the requirements for its admissibility.
The appeal provided for in the Amparo Law allows for a review of the legality of the admission of the direct amparo petition under review. If, upon resolution of the appeal, such admission is confirmed, the decision constitutes res judicata with respect to the admissibility requirements analyzed; therefore, those requirements need not be reexamined when ruling on the merits, unless there is a separate ground for inadmissibility or an exceptional circumstance not previously considered.
Digital registration number: 2032770 / Thesis: P./J. 202/2026 (12th)
Case Law of the Supreme Court of Justice of the Nation
The amount of the principal claim in an action for enforcement of an insurance contract may be determined only upon enforcement of the judgment.
In an action for performance of an insurance contract, the plaintiff need only prove the existence of the contract and the occurrence of the insured event. The amount claimed as compensation is not a separate element of the action; therefore, it must be quantified in the final judgment when sufficient evidence exists; otherwise, it may be determined during enforcement of the judgment, provided that the basis for its calculation is established.
Digital registration number: 2032768 / Thesis: PR.A.C.CS. J/10 C (12th)
Case Law of Regional Circuit Courts
A company's liability for business acts performed by someone acting on its behalf and the allocation of the burden of proof.
Anyone seeking to hold a company liable for the acts of a person acting on its behalf must prove that the act is related to the activities entrusted to that person. Once this has been demonstrated, it is up to the company to prove the facts on which it bases its claim to exclude liability. However, merely demonstrating that internal limits existed or that the person exceeded their authority is not sufficient to exempt the company from liability, especially when the act is part of a transaction inherent to its business activities and the company possesses the necessary documents to substantiate the authority of its representatives.
Digital registration number: 2032785 / Thesis: VI.1o.A. J/2 K (12a.)
Case Law of the Circuit Courts of Appeals
A defective complaint may be replaced when the amparo proceeding is improperly dismissed.
In administrative matters, a deficient complaint may be substituted when there is a clear violation of the law that prejudices the complainant and leaves the complainant without a defense. This occurs, for example, when a case is improperly dismissed and a court is prevented from analyzing the legality or constitutionality of the act being challenged, even if the affected person has not expressly pointed out that irregularity in their arguments.
Digital registration number: 2032760 / Thesis: VII.1o.C.5 K (12a.)
Individual Opinion of the Circuit Courts
Failure to file a joinder in an amparo proceeding does not preclude challenging the new judgment issued to enforce an amparo ruling.
The failure to raise a joinder in an amparo proceeding does not prevent the party that obtained a favorable ruling from alleging procedural or substantive violations in a new amparo proceeding against the judgment rendered in compliance with that ruling that harms its interests. Preclusion applies only to procedural violations that should have been raised in a timely manner, provided that it would have been possible to do so.
Digital registration number: 2032780 / Thesis: VII.1o.C.4 K (12a.)
Individual Opinion of the Circuit Courts
The parties have the right to present evidence in a proceeding concerning excessive or insufficient compliance with the final suspension.
An incident involving excessive or insufficient compliance with a definitive suspension requires that all parties be given the opportunity to present evidence and present their arguments, even though the burden of proof lies primarily with the responsible authority to demonstrate that it complied with the suspension. If this opportunity is denied, the parties’ right to a fair hearing is violated, and this may result in the proceedings being reopened if the omission affects the outcome of the decision.
Digital registration number: 2032784 / Thesis: I.12o.C.1 K (12a.)
Individual Opinion of the Circuit Courts
The appointment of a special representative ensures that the rights of a minor are adequately protected in an amparo proceeding.
The court must appoint a special representative for a minor when the person acting as the minor’s legal representative is unable to do so or fails to adequately protect the minor’s interests, whether due to absence, impediment, refusal, conflict of interest, or another justified cause. This includes cases in which a parent files an amparo petition without properly defending the minor’s rights, in order to ensure that the minor receives effective representation in accordance with his or her best interests.
This publication was prepared byDaniel Majewski del Castillo,Guadalupe Villa Figueroa,Raúl Alonso Flores Hernández, and Frida Isabel Velázquez Vargas.
