Listening to BBC Radio while preparing my supper in the kitchen as usual, I picked up on the news about the “Ban of E-cigarette use indoors” by the World Health Organization (WHO). What interested me most were the arguments from both sides: WHO and representatives of E-cigarette industry. One of the arguments by WHO for the ban was that scientific evidence is not certain that the use of E-cigarettes does not harm human health (other arguments were that no evidence shows that E-cigarettes help smokers quit, and that probably the use of E-cigarettes had a bad effect on juveniles or even encouraged them to take up smoking). Since the producers had not proven the safety of the E-cigarette, they should be banned. On the contrary, representatives of the E-cigarette industry argued that although the absolute safety of the use of the E-cigarette had not been proven scientifically, this lack of scientific certainty cannot be used as a reason for the ban (besides, using the E-cigarette is most certainly less harmful than smoking normal cigarettes). They also argued that the regulation must be proportionate.
It seems apparent to me that both sides made reference to the precautionary principle, though not explicitly. However, their interpretation of the meaning of the same principle differs. What is the precautionary principle then? Since the precautionary principle applies in different policy areas (mostly in the areas of environmental protection, food safety, public health and international trade) at both international and national levels, I am not attempting to present a universal definition. Instead, I take international environmental law (“IEL”) as an example to display the meaning of the precautionary principle, bearing in mind that the precautionary principle in other areas would have a very similar meaning. A widely accepted definition of the precautionary principle in IEL can be found in Principle 15 of the 1992 Rio Declaration on Environment and Development. It states:
“In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. 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.”
Clearly, this definition of the precautionary principle (the terms “the precautionary approach” and “the precautionary principle” are used interchangeably in this post) revolves around the notion of scientific uncertainty (of the harmful effects on the environment). It emphasizes that scientific uncertainty cannot serve as full justification for not taking preventive measures or postponing measures (for the protection of the environment). It also lays down three limitations to the application of the precautionary principle. First, the precautionary principle applies only when the potential harmful effects are serious or irreversible. Secondly, the preventive measures shall be cost effective. Thirdly, when preventive measures are taken, the practical capabilities of States should be taken into consideration.
In theory as well as in practice, however, controversial questions arise. First, who is to prove that the threshold of risk - threats of serious or irreversible damage – has been crossed? Shall the burden of proof be allocated to those proposing to undertake a potentially risk-generating activity? Namely, whether a reversal of burden of proof is to be applied. Secondly, what kind of preventive measures are appropriate in a specific case? Shall the regulator balance the benefits and risk (of the proposed activity), or weigh up one risk (of the proposed activity) against another risk (of alternative activities) when it decides what kind of preventive measures are to be employed?
Those questions are also at issue in the E-cigarette case. First of all, the adverse effects on human health of the use of the E-cigarette have not been scientifically proven or disproven. Secondly, in the situation of scientific uncertainty, WHO, as the regulator, argued for taking a preventive measure. The measure it chose was to ban the use of E-cigarettes indoors. To justify its argument, it made use of the legal device – the reversal of the burden of proof i.e. asking E-cigarette producers to prove the safety of their products. The representatives of the E-cigarette industry, however, rejected a reversal of the burden of proof. They interpreted the precautionary principle in this way: scientific uncertainty does not necessarily result in taking a preventive measure. They challenged the appropriateness of the WHO measure since it was adopted in the absence of a weighing process and a ban in this case was overregulated.
The differing interpretations of the precautionary principle by the two sides in the E-cigarette case illustrate exactly the serious controversy over the legal meaning of the precautionary principle, and as a result, the difficulty in its application which is by no means a new phenomenon. In fact, the precautionary principle has been invoked many times before international judicial institutions. In almost all cases, the parties were divided significantly in the interpretation of the precautionary principle, though they did not object to the principle as such, and the judicial institutions were basically reluctant to apply it. Strictly speaking, the precautionary principle has not yet been applied by an international judicial institution until now.
Therefore, it is fair to conclude that while the precautionary principle requires policy makers to be prudent, the principle itself should also be applied prudently. In the E-cigarette case, I believe that WHO should have provided more evidence for the necessity of a regulation and given better reasons for choosing a ban as the regulatory measure. Arguing for a reversal of burden of proof and imposing a ban based upon the failure of proving the absolute safety on the part of E-cigarette producers is a too simplified method in a complicated process for the application of a principle with a controversial legal meaning.