On March 9, 2021, Greenpeace filed an amparo, an emergency proceeding, against the National Institute of Ecology and Climate Change, the Inter-secretarial Commission on Climate Change, the Secretariat of Environment and Natural Resources, the Council of Climate Change, and the Mexican President, challenging Mexico’s revised Nationally Determined Contributions (NDC). The NGO argued that the NDC failed to respect the principle of non-regression in human rights law. In its original 2015 NDC, Mexico committed to a 22% reduction in GHG emissions by 2030 as compared to 2000 levels. In the revised NDC presented in December 2020, Mexico raised the baseline against which the GHG emission reduction is measured. Greenpeace argued that the updated NDC would effectively cause the additional emission of 14 million tons of CO2e; (ii) eliminate the peak of GHG emissions stipulated for 2026; (iii) rule out the 50% reduction target for 2050, which would nullify the mitigation horizon in the medium and long term. Greenpeace asked the court to suspend the effects of the 2020 NDC.
On July 14, 2021, the Judge ruled against Greenpeace. On July 30, 2021, Greenpeace appealed the decision. The District Court court failed to notify the Eleventh Collegiate Court of the First Circuit in Administrative Matters, which was deciding the matter of the injunction to suspend the effects of the contested acts.
On September 21, 2021, the Eleventh Collegiate Court of the First Circuit in Administrative Matters (not knowing of the previous decision) decided to suspend Mexico’s 2020 NDC. The court considered Mexico’s mitigation commitments to be regressive, in violation of the law. In its place, Mexico’s 2015 commitments on mitigation and adaptation for the 2020-2030 period would apply, and the injunction would remain in effect until a superior court ruled on the Judge's decision.
On December 15, 2022, the Eleventh Collegiate Court of the First Circuit in Administrative Matters heard the plaintiff’s appeal. The Collegiate Court ruled against Greenpeace, deciding that the plaintiff did not provide sufficient evidence to prove that the NDC is regressive, nor did it prove that Mexico could emit up to 14 million tons of CO2e more in comparison to the 2015 targets. Therefore, the case was dismissed.