Alternet's Chris Mooney, on The Fraud of 'Sound Science' as used by the GOP:

Much of the modern conservative agenda on science is embodied in the enigmatic phrase "sound science," a term used with increasing frequency these days despite its apparent lack of a clear, agreed-upon definition. In one sense, "sound science" simply means "good science." Indeed, when unwitting liberals and journalists have been caught using the phrase - which happens quite frequently - it appears to have been with this meaning in mind.
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A short history of the phrase "sound science," and its development into a mantra of the political right, clearly demonstrates its anti-regulatory, pro-industry slant. Strategic uses by the business community trace back at least to Dow Chemical Company president Paul F. Oreffice's 1983 claim that a $3 million program to allay fears of dioxin pollution in Michigan would use "sound science" to "reassure" the public - i.e., downplay risks. To rebut Dow's claims, a young South Dakota representative named Tom Daschle promptly released results from a confidential study suggesting that dioxin damages the immune system. In this incident, it's possible to see the first sprouting of a political debate over "sound science" that would bloom into a full schism a decade later.

In early 1993, Philip Morris and its public relations firm, APCO Associates, created a nonprofit front group called The Advancement of Sound Science Coalition (TASSC) to help fight against the regulation of secondhand smoke. To mask its true purpose, TASSC assembled a range of anti-regulatory interests under one umbrella, and rarely, if ever, explicitly challenged the notion that secondhand smoke poses health risks. Instead, the group, headed by former New Mexico governor Garrey Carruthers, described itself as a "not-for-profit coalition advocating the use of sound science in public policy decision making." Still, at the very least TASSC implied that the science of secondhand smoke was bogus. For example, in 1994 the group released a poll of scientists suggesting that politicians were abusing science on issues such as "asbestos, pesticides, dioxin, environmental tobacco smoke or water quality."

At roughly the same time, fortuitously or otherwise, the incoming Republican Congress of 1994 adopted "sound science" as a mantra. Just a week after the November 1994 elections, Newt Gingrich and company had set the tone. "Property rights" and "sound science" had become "the environmental buzzwords of the new Republican Congress," a Knight-Ridder news report noted. The perceptive report also included a definition of "sound science," which suggested it meant much more than simply "good science." Instead, the point was deregulation: "'Sound science' is shorthand for the notion that anti-pollution laws have gone to extremes, spending huge amounts of money to protect people from miniscule risks."

Calls for "sound science" closely accompanied the push to enact a key tenet of the Republican Party's "Contract With America" - regulatory "reform," an industry-backed gambit to provide steep hurdles to future environmental, health, and safety regulations. Reform bills sponsored in 1995 by Gingrich and Senate Majority Leader Bob Dole would have imposed stringent new rules on the process by which the Environmental Protection Agency and other government bodies conducted science-based risk assessments to determine whether a particular danger should be regulated. The proposals demonstrated that the new Republican majority wanted nothing less than to become government's science cops – and to start fixing the tickets of industry.

The leading regulatory reform proposals would have legislated the very nature of science itself. They prescribed a one-size-fits-all standard for risk assessment across very different government agencies, potentially stifling scientific adaptability. The bills also would have erected a "peer review" process to scrutinize risk assessments with large potential regulatory impacts - one that would have not only bogged down the regulatory process, but also allowed industry scientists to participate in or even dominate reviews. In addition, regulatory reform would have created new opportunities for federal court challenges over agency risk assessments - an ideal opportunity for business interests to engage in scientific warfare over analyses they didn't like. The whole process, Public Citizen lawyer David Vladeck wrote at the time, smacked of an attempt to achieve "paralysis by analysis."
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Ultimately, the regulatory reformers went too far and their proposal died in the Senate -but not before it had helped crystallize a new conservative lexicon. In a 1996 report, the late Rep. George Brown, ranking Democratic member of the House Science Committee, issued a long and anguished reflection on the Republican Party's adoption of "sound science" principles entitled "Environmental Science Under Siege: Fringe Science and the 104th Congress." Brown's report provides a powerful riposte to the "sound science" movement, whose proponents he accused of having "little or no experience of what science does and how it progresses."
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Conservatives and liberals both agree that science is crucially important for making public policy. But the answers provided by scientific research are rarely certain and always open to disputation or challenge. When conservatives today call for "sound science," the evidence suggests that what they really want is to hold a scientific filibuster - and thereby delay political action.

No where in the Republican Party is this attitude more prevalent than in the Bush Administration, which has virtually waged war on the environment based on the "sound science" argument. It's actually an interesting dichotomy, the Republicans resist enacting environmental legislation due to so-called lack of sound science, yet they were willing to send our troops to war based on the flimsiest of evidence. Anyone who thinks their motives are anything but self-serving is delusional!