Scientists and politicians do not play by different rules. Scientists and politicians alike are human, and must be understood in human terms. Evidence may be objective, but under the white coats of those determining its value lie some very human reactions: and so human rules apply to interpretation of evidence. Scientists, no less than politicians, make judgements based on academic opinion, party platform, grant contribution, advertising copy, and opponents' motivations. In science as in politics, there are no points for second place.
Behind each media theory-of-the-hour focus exist several theories capable of explaining observed data: many forced into obscurity solely because they challenge the scientific status quo. Traditionally such obscurity has been easy to accomplish. Papers are or are not accepted to journals and conferences based as much on the reputation of their authors (and of the theories supported by those authors) as on scientific merit. Papers contrary to current scientific canon are less likely to be accepted. Not only is it more difficult to disprove absolutely than to support marginally, but more rigorous testing and stricter p-values are commonly (if unconsciously) demanded of negative papers than of positive ones. Nor does the negative result usually achieve patentable breakthroughs -- and may indeed discourage continued use of the old -- while grant monies, public and private, continue to be contingent on established reputation, as measured by published papers.
Yet editors are human too, as much trapped within their reputations as those seeking to publish revolutionary results: for it is upon the editor that any misstep will rebound. Peer review circumvents the editor's absolute veto by dividing the paper's fate among one to three peer reviewers, selected from among those with established reputations. Certainly those who have accomplished the most and earned a credible reputation would normally be most capable of making the best assessments: were true objectivity possible. Instead, peer review creates only the illusion of objectivity, and adds to it the illusion of objective consensus. It does not grant a paper a more objective review. Yet many medical consensus guidelines are not even peer-reviewed - and so are especially vulnerable to advertisers keeping the journal solvent.
The Internet has changed these rules. One's decisions need no longer be decided by a scientific clique: but one must accept the presence of fallacy as well as potentiality. Much of what is on the Internet is total myth -- but some is not. We risk drowning in information -- but complete suppression of ideas is no longer viable. Except, perhaps, by public opinion: as shaped by the scientific consensus and the media sanction.
In this "free-for-all" environment it becomes one's own responsibility to become a discriminating reader, teaching oneself to evaluate what one reads. Not all debunking is the result of persecution: but one should remember precisely what is meant by "theory." A hypothesis expresses potential results. A theory is a more widely casting hypothesis, proposed as a "best fit" explanation for the observed evidence. It may be developed empirically to explain obtained results, or built on the groundwork of previous theories. Future experiments may support the theory, or they may disprove it. The greater the number of experiments showing support, the more likely the theory becomes: yet it must remain theory, a human explanation for human observation of objective evidence. No experiment can prove, absolutely. It can only provide support for one explanation or another, or, potentially, provide support against existing explanations.
Yet the stakes behind the validity of a scientific theory can indeed be much more serious than sports. Too serious, perhaps, to allow theory to dogmatize into scientific canon on the sole basis of who supports which party, or who stands to gain. Not to take into account a potential worst case scenario, be the person politician or scientist, is nothing less than criminal: but to prepare for the worst is not the same thing as automatically accepting that worst theory as fact. Political rhetoric may not alter scientific evidence, but to assume that scientific evidence interpreted as supporting a specific theory is identical to equating that theory with fact is worse than irresponsible.
Is it not by refusing to acknowledge existing lenses of subjective medical consensus that we most distort our own potential vision?