In the opening months of his administration, US President Barack Obama gathered scientists in the grand East Room of the White House to promise that things would be different on his watch. The president was there to sign a new memo on scientific integrity that directed agency heads not to meddle in the decisions of their scientific staff.

In his speech, Obama pledged that his ambition was “about letting scientists like those here today do their jobs, free from manipulation or coercion, and listening to what they tell us, even when it's inconvenient — especially when it's inconvenient”.

Yet events earlier this month saw Obama demonstrate a blatant betrayal of these principles, when he defended a decision by Kathleen Sebelius, US secretary of health and human services, to override a drug approval by the Food and Drug Administration (FDA).

What is most infuriating is the casual jettisoning of careful evidence on this contraceptive's safety.

Scientific staff at the drug-regulatory agency, including paediatricians, obstetricians and gynaecologists, reached a key determination earlier this year involving Plan B One-Step (levonorgestrel), a single-dose 'morning-after' contraceptive pill. They concluded that it is safe and effective for girls younger than 17 years of age without the currently required prescription — and that these girls could use it correctly without a physician's help. (Older women can already get the contraceptive over the counter.) The FDA experts came to their decision after conducting the usual extensive review, including a comprehensive survey of the literature and data from the pill's manufacturer, Teva, headquartered in Petah Tikva, Israel. These data included age-specific studies designed specifically to address the agency's standards for non-prescription drugs. The scientific staff concluded that, as FDA commissioner Margaret Hamburg put it earlier this month: “There is adequate and reasonable, well-supported, and science-based evidence that Plan B One-Step is safe and effective and should be approved for nonprescription use for all females of child-bearing potential.”

So much for science. One day after Sebelius announced that she was overruling the agency and denying over-the-counter access to the morning-after pill to females under 17, Obama, questioned by a reporter, said that he agreed with her decision, and added that, “as the father of two daughters” he lauded the application of “common sense”.

He said: “The reason Kathleen made this decision was she could not be confident that a 10-year-old or an 11-year-old go into a drugstore, should be able — alongside bubble gum or batteries — be able to buy a medication that potentially, if not used properly, could end up having an adverse effect. And I think most parents would probably feel the same way.”

Where to start? Never mind that the most powerful man in the world didn't bother to get the basic facts right: the contraceptive, even for non-prescription use, is stored behind the pharmacy counter and not “beside bubble gum and batteries”. And never mind the throwback paternalism implied by elevating his own opinion as “the father of two daughters”. What is most infuriating about Obama's response is the casual jettisoning of careful and convincing evidence on this contraceptive's safety and effectiveness, even for young adolescents, and their ability to comprehend the labelling. (It essentially says: “Take this one pill, now.”) With it went his own promise to the thousands of scientists whose hard work and science he had pledged to respect, “especially when it's inconvenient”. It certainly is inconvenient, on the cusp of an election year, in what is at heart a deeply conservative country, to acknowledge that young adolescents can and do have sex, and that they may not have thought out the potential consequences in advance. So inconvenient, apparently, that the work of the scientists, who spent long hours weighing risks and benefits for the public good, must be thrown under a bus.

Most troubling of all is that Obama has set a precedent for overriding science. Sebelius's trampling of a drug decision by the FDA is the first in living memory. If it is acceptable for her to override the agency for this year's reasons of political convenience — or, for that matter, for reasons of heartfelt belief — what politically loaded drugs will next come under the axe?

If there is a silver lining here, it is that some agencies seem to be listening to what the president says rather than following what he does. Several are working hard to put in place the integrity policies he mandated nearly three years ago (see page 425). The Department of Health and Human Services has not revealed where it stands on crafting such a policy of its own.