Over at Opinio Juris, Roger Alford has an interesting post on the precautionary principle. Among other things, he notes:
Of course, there are mild and strong versions of the precautionary principle. As Cass Sunstein has noted in this article, a mild version rather benignly posits that "a lack of decisive evidence of harm should not be a ground for refusing to regulate." But a strong version would maintain that "when there is a risk of significant health or environmental damage to others or to future generations, and when there is significant uncertainty as to the nature of that damage or the likelihood of the risk, then decisions should be made so as to prevent such activities from being conducted unless and until scientific evidence shows that the damage will not occur." In essence, the strong version proposes a standard of "when in doubt, regulate."
There's a lot more in the post as well.
