It's hard to imagine a more Orwellian, euphemistic name for a childish debating trick masquerading as serious legislation. Winston Smith of Philosoraptor, unflappable as ever, picks it apart and demonstrates the inherent danger in this latest piece of neo-con chicanery.
As you know and as the article makes clear, many (perhaps even most) arguments in science--and out of formalized science, for that matter-- involve assessing the weight of conflicting evidence for and against some hypothesis. We can think of this as a kind of UNbalancing, analogous to weighing two items of extremely similar mass to determine which is heavier. If we build an inaccurate scale--or if we put a finger on the scale, continually nudging one side up or down depending on some antecedent preference about which we'd like to weigh more--the results of our efforts are basically valueless.
One way of cheating the system is to employ illegitimately differential standards of proof. . . According to this [Washington Post] article, the DQA is being used to nudge the scales in favor big business. When the weight of evidence indicates, for example, that some substance is harmful, this act allows those who oppose regulation to arbitrarily raise the required standards of proof.
Given that evidence is often available on both sides of any important question, if you give me the ability to raise and lower the standards of evidence at my whim, I can frequently torture the data to support whichever conclusion I prefer. The application of systematically differential standards is an old trick of pseudoscientists.