The truth is out there . . .

Revere, a while back, described the conference on "Scientific Evidence and Public Policy," sponsored by the Project on Scientific Knowledge and Public Policy, which took place in March 2003. The wheels of justice may grind slow, but the wheels of scientific publishing grind at least as slowly. Papers from the conference have just been published in a special issue of the American Journal of Public Health. I'm kind of an old fashioned guy, so intrigued as I was by Revere's post, I waited for the dead tree version to arrive in my mailbox.

As it turns out, despite the title of the conference, the major focus of the papers is not policy making by the executive and legislature so much as it is expert testimony in civil litigation. Nevertheless many of the same issues arise in all contexts. How are laypersons -- judges, juries, elected officials, political appointees overseeing regulatory agencies -- to evaluate the validity of scientific claims, and the implications of those claims for legal judgments or policy choices?

The papers mostly concern litigation in which large corporations are being sued for damage allegedly caused by toxic exposures to workers, consumers or the general public. These defendants have vast financial resources which they use to disparage the work of scientists whose findings tend to support the plaintiffs, to create an exaggerated impression of scientific uncertainty, and to create an illusion of scientific controversy where little or none exists. Of course we see this in regulatory and lawmaking contexts as well, such as the oil industry and its employees in the White House denying the reality and/or significance of global warming caused by burning fossil fuels.

Unfortunately, contrary to what seems to be the popular belief, there is no simple description of valid "scientific method," no simple screen for good vs. bad science, no paper strip that turns pink when a scientific conclusion is justified, and blue when it is not. This problem is troubling to me because I am very averse to any tyranny of expertise. The notion that we should all accept a conclusion because a distinguished panel of the National Academy of Sciences pronounces is as repugnant to me, in some ways, as the notion that we should accept pronouncements by the Pope, or the long-dead biblical scribes. Indeed, many people do not see any evident difference between the two propositions and they think of science as just another religion; so why is evolution to be privileged above creationism?

In the thimerosal case, I plead guilty with extenuating circumstances. While I have some ability to evaluate the scientific literature on this question on my own, I principally ask people to agree that there is no good evidence that thimerosal causes autism, let alone is responsible for an autism epidemic, because that is the scientific consensus, and Kennedy lacks relevant expertise. In this particular case, Eli Lilly has not had to spend millions of dollars on muddying the waters because Kennedy has no credible scientific allies. Completely independent experts, who are not paid by the vaccine industry and owe them no allegiance, have reviewed the evidence and found it wanting.

But this obviously does not satisfy the many parents who are convinced that they know why their children are autistic, who are angry about it, and whose champion is Robert Kennedy Jr. And after all, why should it? Is he not a credible person? And do people who lack exactly the right doctorates have no right to opinions about scientific questions? Where would that leave me, with my Ph.D. in social policy, writing a blog that is far more wide ranging?

This blog is largely a search for answers. Right now, I don't have them.

BTW: You can read the conference papers here, fortunately, because the American Journal of Public Health is subscription only. This is one of my biggest annoyances: scientific journals are extremely expensive, you can't buy them on the newsstand, and you can't read them on the Internet unless you happen to have a faculty appointment somewhere. On the other hand, you can read everything there is from the Discovery Institute and, for that matter, RFK, free of charge. How about the American Public Health Association putting the public in public health by letting the public read its journal?