According to his mission statement, the U.S. surgeon general "serves as America's chief health educator by providing Americans the best scientific information available on how to improve their health and reduce the risk of illness and injury."

The reality, according to testimony before Congress, is that the surgeon general is pressured to trim or ignore the best scientific information and substitute the political opinions of the administration. This has gone on for years and did not begin with President Bush. Three former surgeons general testified before the House Government and Reform Commission on Tuesday.

Dr. C. Everett Koop said he was discouraged by top officials in the Reagan administration from discussing the then new AIDS epidemic, although he did so anyway. Dr. David Satcher told how the Clinton administration did not want him to issue a report showing that needle-exchange programs were effective in reducing disease, although he did so.

Dr. Richard H. Carmona served a term as surgeon general from 2000 and 2004 and was not asked back. He portrayed those years as one political intervention after another. Dr. Carmona told the committee that the Bush administration required his silence on issues including stem cells, emergency contraception and sex education. It tried to delay and water down perhaps the most notable report of his tenure, on the dangers of secondhand smoking.

He said he was ordered to mention President Bush frequently in speeches and was even discouraged from attending the Special Olympics because it was supported by a rival political family, apparently the Kennedys. As for global warming, he found no interest among administration officials in the science; they dismissed it as a liberal cause.

Despite its usual denials, the White House is not persuasive in the face of so many damning particulars offered by Dr. Carmona under oath. It is clear that it has sought to turn a bully pulpit for public health into a platform for political positions, and Americans should not stand for it.

On Thursday, Dr. James W. Holsinger, President Bush's nominee to be surgeon general, assured senators at his confirmation hearing that he would resign before putting ideology over science. He said a 1991 paper about homosexuality and health -- interpreted by opponents of his nomination as being evidence of anti-gay prejudice -- no longer represents his views. Yet, given the record of the administration in currying favor with the religious right, it's reasonable to suspect that his controversial views helped recommend him for the job in the first place.

He should not be given the benefit of the doubt. Surely a qualified candidate can be found who, unlike Dr. Holsinger, would have the confidence of the public from the start. After this week's disturbing testimony, Americans need no further cause for skepticism in a venerable office shamed by political pressures.