Between Precaution and Prevention: Scientific Uncertainty and Implementation of the Precautionary Principle

Abstract The cause and effect of risks like the destruction of the environment are global and multiplied now, and international efforts are needed to tackle new aspects of global environmental risks. However, to address the potential risks, international law should incorporate some degree of "uncertainty" and probable "risks" into the normative picture. The precautionary principle is an important instrument in tackling this "grey area" of uncertainty. Having its roots in German domestic law, this principle saw its widespread acceptance in international documents since the 1980s. The legal nature and status of the precautionary principle are under discussion among international legal scholars, while international courts and tribunals have been reluctant to apply this principle or to recognize its normative status explicitly. But this principle has a firm relationship with other existing norms and concepts for environmental protection, and its existence as a tool for initiating proactive measures in the face of uncertain risk is valuable. Although the precautionary principle shares a common continuum of timeframe with the principle of prevention, the dividing line between these two principles is rather vague. A continuous assessment as a part of risk management becomes necessary for both principles to operate effectively. It is for the decision-makers to draw the line, but this by no means leaves them in a free-hand position: prudent and cautious decision-making should be made in the face of scientific uncertainty for the effective implementation of the precautionary principle.