The Bush administration has worked overtime to manipulate or conceal scientific evidence  and muzzled at least one prominent scientist  to justify its failure to address climate change.

Its motives were transparent: the less people understood about the causes and consequences of global warming, the less they were likely to demand action from their leaders. And its strategy has been far too successful. Seven years later, Congress is only beginning to confront the challenge of global warming.

The last week has brought further confirmation of the administration’s cynicism. An internal investigation by NASA’s inspector general concluded that political appointees in the agency’s public affairs office had tried to restrict reporters’ access to its leading climate scientist, Dr. James Hansen. He has warned about climate change for 20 years and has openly criticized the administration’s refusal to tackle the issue head-on.

More broadly, the investigation said that politics played a heavy role in the office and that it had presented information about global warming “in a manner that reduced, marginalized or mischaracterized climate-change science made available to the general public.”