I've been meaning to write about this issue, but the sheer scope of it has caused me to procrastinate. Now, however, someone has done the work I should have (and then some), and things appear to be coming to a head. Angry Bear at The American Street links to this story from the Union of Concerned Scientists:

...more than 60 leading scientists—including Nobel laureates, leading medical experts, former federal agency directors and university chairs and presidents—issued a statement calling for regulatory and legislative action to restore scientific integrity to federal policymaking. According to the scientists, the Bush administration has, among other abuses, suppressed and distorted scientific analysis from federal agencies, and taken actions that have undermined the quality of scientific advisory panels.

As AB notes, the place to go for coverage of this issue is Chris Mooney's blog; his take on the statement is here. See also the "politics" category at Pharyngula for some bracingly bilious background on the Bush administration's hostility to science.

You can read the statement here, see a list of heavyweight signatories here, and if you're a scientist you can add your mark here (yes, I signed it). The statement itself is part of a wider campaign in which I urge everyone to get involved. One of the focal points of the campaign and the force behind the signed public statement is a report entitled Scientific Integrity in Policymaking: An Investigation into the Bush Administration's Misuse of Science; you can download the full report or executive summary as pdf files from here. You should read the whole thing, but here are the basic findings:

1. There is a well-established pattern of suppression and distortion of scientific findings by high-ranking Bush administration political appointees across numerous federal agencies.

2. There is strong documentation of a wideranging effort to manipulate the government’s scientific advisory system to prevent the appearance of advice that might run counter to the administration’s political agenda.

3. There is evidence that the administration often imposes restrictions on what government scientists can say or write about “sensitive” topics.

4. There is significant evidence that the scope and scale of the manipulation, suppression, and misrepresentation of science by the Bush administration is unprecedented.

Remember how the media kept calling Howard Dean "angry"? Listen: if you're not angry, you haven't been paying attention.