The Supreme Court punted one of the term’s most anticipated commercial cases last month, affirming a lower-court decision in Warner-Lambert v. Kent in a tied vote (Justice Roberts recused himself). The plaintiffs in Warner-Lambert had successfully charged the maker of Rezulin—a diabetes drug approved by the Food and Drug Administration but later withdrawn due to safety concerns—with failing to warn consumers adequately about possible side effects, though the drug was labeled just as the FDA had directed. This fall, the Court will hear arguments in Wyeth v. Levine, another case involving allegations that the FDA provided inadequate warning-label information. Here’s hoping that the Court sides with the FDA, which is already under tremendous pressure to be risk-averse when it approves new drugs and drug labels.

For years, the FDA was complicit in a phenomenon known as “overwarning.” The agency repeatedly required drug makers to include this or that rare, harmless, or unproven possibility on the warning labels accompanying prescription drugs. But the tissue-thin, ever-lengthening inserts—covered on both sides with microscopic print—become more daunting every year, and many people gave up trying to read them. In his new book, Overdose, University of Chicago law professor and Manhattan Institute visiting fellow Richard Epstein explains why the FDA was so cautious: “Some, perhaps many, drugs are likely to have potent and adverse side effects that place harried FDA officials in the public crosshairs. The agency’s mission responds to these political pressures by encouraging key public officials to give greater weight to the risk of allowing bad drugs on the market than to the risk of keeping good ones off of it.” Overwarning was often the only way that the FDA could bring itself to approve a new drug at all.

Finally, the unreadable inserts sparked a backlash within the FDA, which is attempting to strike a balance between consumers’ need to know and the self-defeating length and complexity of drug labels. It has reduced the length of label instructions and authorized a “highlights” section providing a brief summary of critical information. “If you put too much junk on the label, people don’t understand it,” Randall Lutter, the FDA’s deputy commissioner for policy, told the Washington Times.

The FDA’s efforts may be undone, however, by trial lawyers suing pharmaceutical companies in state courts for “failure to warn.” These mass-tort lawsuits typically come in herds of thousands of look-alike cases, each alleging that a drug maker didn’t adequately inform the plaintiff about every conceivable danger, no matter how minute. Failure-to-warn lawsuits all too often succeed, since each jury sees only an injured plaintiff—not the thousands, or even millions, of other consumers who have benefited from a drug. It’s easy for plaintiff’s lawyers to argue that one more warning should have been added to an already lengthy label, even though unreadable labels actually make consumers less safe.

“The ‘highlights’ section may be a good idea for consumers, but it is a lawsuit waiting to happen for drug companies,” argues the American Enterprise Institute’s Ted Frank, a former pharmaceutical lawyer. “Trial lawyers will use 20/20 hindsight to allege that the ‘highlights’ section improperly omitted something deeper in the warnings. Companies shouldn’t be caught in that no-win situation.”

In a preamble to a new rule it issued in 2006, the FDA drew a line in the sand, declaring that “FDA approval of labeling . . . preempts conflicting or contrary state law.” The question the Supreme Court must answer this year is whether the federal agency’s decisions do, in fact, override the state lawsuits motivating drug companies to overwarn. The FDA has shown courage by tackling the overwarning problem; let’s hope that the Court backs it up.

Marie Gryphon is a former practicing attorney and a senior fellow with the Manhattan Institute’s Center for Legal Policy.