The paper describes a dataset obtained through the detailed analysis of 688 judgments issued by the Mexican Supreme Court in constitutional controversies related to separation of power disputes within federalism conflicts centering on those involving the constitutionality of legislation. The data was collected in June 2022, after which judgments were extracted from the database of the Mexican Supreme Court and manually classified. With over 90 0 0 data points, the dataset provides information such as the judgment id, the year resolved, the plaintiff, the level of government sued, the presence of the Federal District as a party, the remedy that procedurally could be sought, and the type of normative provision challenged. Furthermore, the dataset provides a timeconsuming manual classification of the outcome of all challenged provisions, sorting them as upheld, invalidated, dismissed due to the supermajority requirement to strike down legislation, or dismissed on formal procedural grounds. The dataset could be of potential use to test hypotheses related to the centralizing nature of constitutional courts and other bodies resolving federalism disputes, testing the impact of supermajority rules on courts, and employing data for crosscomparison of unconstitutionality rates. The dataset has also laid a solid foundation for further annotation efforts, which may be undertaken by expanding the coded variables. (c) 2024 Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)