Mexico’s Supreme Court recently approved judicial precedent in Amparo proceeding 307/2016. In its decision, the Court relied on the precautionary principle to hold that environmental impact assessments are required for any project that may have an adverse environmental impact. This means that any project not backed by an environmental impact evaluation may be subject to judicial review and suspension.
The precautionary principle is part of the Rio Declaration, commonly referred to as the Earth Summit, which was adopted by 178 Member States in 1992. It contains 27 principles aimed at protecting the environment and achieving sustainable development. The precautionary principle or precautionary approach (principle 15) states that “Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation.”
The precedent’s text may be found here (Spanish text).