Philip Cooney, former chief of staff at the White House Council on Environmental Quality, has acknowledged at a House hearing some of the changes he made were “to align these communications with the administration’s stated policy” on climate change.

Rep. Henry Waxman, D-Calif., chairman of the House Government Reform Committee, said “my concern is that there was a concerted White House effort to inject uncertainty into the climate debate.”

Waxman’s committee also heard from James Hansen, director of NASA‘s Goddard Institute for Space Studies and one of the country’s leading climate scientists, who said the White House repeatedly tried to control what government scientists say to the public and media about climate change.