O princípio da precaução nas políticas ambientais globais

The article evaluates the application of the precautionary principle at the international level. It employs a comparative study of four cases in global environmental politics: ozone depletion, acid rain, deforestation and coral reef degradation. Contrary to widespread academic notions, the precautionary principle is not widely applied in international environmental policy. The empirical record shows that governments abstain from regulatory policy when they face uncertainty about key aspects of ecological problems. The key question that the literature has ignored is: what kind of uncertainty? Indeed, states do take action when the extent of ecological problems is unknown. However, uncertainty about the transboundary consequences of alleged problems prevents international policy. Existing scholarship has misappraised the status of PP in international law, by underspecifying when PP is applied and under what kind of scientific uncertainty.