Only the best science belongs in court: Limits on witness testimony needed

Judges need to ensure that expert witness testimony that goes before a jury is based on ideas that are generally accepted in the medical community.

Editorial. June 19, 2006.

Most patients wouldn't want to receive treatments that haven't been generally accepted in the medical community, so why should scientific evidence introduced in the courtroom be treated any differently?

It shouldn't.

But one New York appellate court recently didn't seem to see the problems that judges can create when they admit evidence from an expert witness based on a novel theory that relies on a single case report. Yet it's no stretch to imagine the fallout. Companies pull good medications from the market altogether. More meritless lawsuits clog up the already-loaded-down legal system. Patients may shy away from lifesaving drugs.

The New York court, in Zito v. Zabarsky, incorrectly ruled that a woman who developed an autoimmune disease, polymyositis, can go forward with a lawsuit against the makers of Zocor (simvastatin), even though her experts did not present information that is generally accepted in the scientific community or in peer-reviewed literature.

Instead, her experts put forth a theory of how Zocor and polymyositis are linked. The only scientific literature they could produce was a single, one-page case report from a hospital in Italy published in The Lancet in 1997.

That one-page report -- as other courts have recognized -- is scientifically unreliable because it is simply an account of one patient and makes little attempt to screen out alternative causes for a patient's condition. And in this case in particular, the patient profiled in The Lancet had had major dissimilarities from the New York patient.