The Irrational Precautionary Principle

Article excerpt

Chlorine is a common chemical. It's estimated to be used in the production of 80 percent of all pharmaceuticals. But like most chemicals it can cause problems depending on the dose, what it is mixed with, and how it is used. On one hand, it is used to disinfect drinking water and saves millions of lives every year. On the other hand, it is a component in compounds that are believed possibly to cause cancer or other health problems. When the U.S. Environmental Protection Agency said that a chlorine byproduct presented a cancer risk, officials in Peru stopped using chlorine to disinfect drinking water. The resulting cholera outbreak killed thousands of people.1

The Green Left is today pushing a new legal principle that would seem to mandate that governments around the world repeat this disaster. It's called the Precautionary Principle. It means that any new technology or substance should be banned or restricted until it is proven harmless. Of course, life is rarely that simple. Even if chlorine slightly increases the risk of cancer, it dramatically reduces the risk of dying. But the environmentalist doesn't seem to understand this. Joe Thornton, who was an analyst for Greenpeace, has written: "We need to treat organochlorines as a class. There are 11,000 in commerce plus thousands more that are produced as by-products. It would be truly impractical to regulate them one-by-one. . . . It makes sense to treat organochlorines as guilty until proven innocent."2

Any such rule that treats all chlorine as the same would be impractical. A ban might save a few lives from some forms of cancer, but it would surely cost millions of other lives because of impure drinking water.

The precautionary principle says we shouldn't allow something to happen as long as someone believes it may be a threat and until we can prove that it isn't harmful. A coalition of Green groups enshrined this concept in the Wingspread Statement, which said: "In this context the proponent of an activity, rather than the public, should bear the burden of proof."3

Of course, the "public" referred to is not the public at all but the Green groups themselves.

As Jeremy Leggett wrote in Global Warming: A Greenpeace View: "The modus operandi we would like to see is: 'Do not emit a substance unless you have proof it will do no harm to the environment.'"4 The European Commission took the principle to heart. When it banned animal-growth hormones in 1985 it did so not because of any evidence on hand, but because their safety had not been conclusively proven.

Imagine what the precautionary principle would require in day-to-day living. We are faced with choices and tradeoffs every day. Doing one thing precludes doing other things. We can't go to the movies on Friday night and at the same time visit the in-laws. But the precautionary principle would strip us of entire classes of options. Normally, if you have to decide whether to do something or not, you weigh evidence and choose accordingly. If you applied the precautionary principle instead, you'd do nothing. You would only go to the movies if you could prove in advance that going was better than not going. But how could you do that?

We've all gone to films that were wonderful experiences, and no doubt we've also been to some so abysmal that we walked out before the end. We are certain that the choice was good only after the fact. We can make educated guesses, but we can't prove, in advance, that one option is better than another.

The precautionary principle is tantamount to a coup in legal theory. Say a developer wants to build an apartment and a Green group condemns the plan, saying it's "harmful to the environment." The group would not have to present any evidence to stop the developer. Rather, the developer would have to prove that all possible outcomes from his plan are good. But he could never do that. This would also be true for the inventor, scientist, industrialist, and virtually anyone else who has to deal with the physical world-in other words, all of us. …