The FDA applies bright line rules, backed by criminal penalties, to an area of science where the lines are not bright at all.

There's no mystery to the evil FDA seeks to prevent. It's well-described by the dissent in the Caronia case.

"Hardware stores are generally free to sell bottles of turpentine, but may not label those bottles, 'Hamlin's Wizard Oil: There is no Sore it will Not Heal; No Pain it will not Subdue,' " the judge wrote. Hamlin's Wizard Oil was one of the very first products shut down by the Food and Drug Act in the early 20th century.

But in trying to protect the public from flim-flam, the FDA also risks depriving doctors of early notice of information that could treat and cure their patients.

The irony is that the law allows "all-natural food supplements" to make all kinds of wild promises: They're subject to a different and much more permissive regulatory scheme. You'll hear radio ads for "supplements" that tout these products as "so effective, clinical trials have already begun." Yet for pharmaceutical products, even the news that a clinical trial has been completed was, until this week, forbidden speech unless the FDA gave the word.

That rule has abruptly changed. You're going to hear more talk about what scientists think medicines might be able to do. Where the side effects of a medicine are high, and where good alternatives are available, doctors and patients will want to exercise caution until the final experiments conclude. But where alternatives do not exist, where something is better than nothing, the Caronia ruling offers hope for a more transparent drug-approval regime.

Nothing is certain until the Supreme Court weighs in. But it's looking likelier that freer speech is coming to American medicine.

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