A recent decision of the Mexican Supreme Court holds that public authorities not designated as responsible parties in a constitutionalamparo lawsuit are obligated to take all actions necessary to enforce the terms of an amparo lawsuit judgment. In this manner, eventhough a governmental authority has not been included as a party in an amparo lawsuit, such authority will be obligated to follow theamparo decision. The change yields significant practical value and efficiency. This important decision must be taken into considerationby those individuals and companies who file amparo lawsuits, or who are enforcing amparo judgments, as this decision confirms priorSupreme Court holdings and interpretations in this area. Such prior interpretations sought to provide more complete remedies to amparolawsuit parties and to Mexican federal courts to enforce amparo decisions. The new case broadens this concept to include “all”authorities, whether or not such authorities were designated as responsible parties and not included as participants in the amparo lawsuititself. To cite a practical example, in recent lawsuits filed by taxpayers against the tax known as the Public Utility Tax (Derecho deAlumbrado Publico or “DAP”), the judge could hold an amparo decision invalid as against the Federal Electricity Commission ormunicipal authorities. However, thanks to the new decision and the other prior decisions of the court, these authorities may now bemandated to follow amparo court decisions in their various areas of competency, such as suspending collection of specific taxes or feesand reimbursing such payments to taxpayers, even though the authorities taking such actions were not named parties in the amparolawsuit. See Decision LVII/2007
