On June 5, 2020, four political parties filed a Direct Action of Unconstitutionality for Omission, before the Federal Supreme Court to challenge the Federal Union's alleged failure to adopt administrative measures concerning the Climate Fund. The National Climate Change Fund (Fundo Clima), created by Law 12.114/2009, is an instrument of the National Policy on Climate Change (PNMC, Law 12.187/2009) and aims to ensure that resources support projects or studies and finances activities aimed at mitigating and adapting to climate change and its effects.

The plaintiffs allege that although there is a legal obligation for the Ministry of the Environment to prepare an annual plan for the Climate Fund, it has been inoperative since 2019. The petitioners rely on the obligation of the Union, the States, the Federal District and the Municipalities to “protect the environment and fight pollution in any of its forms” and “to preserve forests, fauna and flora” per the Federal Constitution, as well as the precautionary principle. The plaintiffs also allege a violation of Article 225 of the Federal Constitution, regarding the State's duties to: preserve and restore ecological processes; promote the ecological management of ecosystems; define territorial spaces and its components to be specially protected; and protect fauna and flora. The petition also seeks an injunction to require that the Federal Union: (i) undertake the necessary administrative measures to reactivate the operation of the Climate Fund, with the due availability of resources related to the Climate Fund (including the non-refundable and refundable modalities); (ii) prepare and present the appropriate annual plans for the application of the Fund's resources; and (iii) refrain from making new contingencies of resources from the Climate Fund.

The preliminary ruling by the Supreme Federal Court: (i) adopted an urgency procedure for the action; (ii) summoned the governmental actors involved; (iii) admitted the action as an Argument for Failure to Comply with a Fundamental Precept (ADPF, another constitutional procedure aimed at enforcing the principles and values in the Constitution); and (iv) scheduled a public hearing on September 21 and 22, 2020, creating a deadline for interested parties to express their interest in participating, until August 10, 2020.