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When scientific evidence wavers, courts apply their own standards

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Silicone breast implants may or may not cause disease. Scientific studies disagree. But that uncertainty hasn’t prevented implant manufacturers from putting $4.25 billion into a settlement fund for the thousands of women who sued for damages.

Researchers debate whether electromagnetic fields are harmful, but a Washington state judge has allowed an aluminum worker exposed to them to file a claim for his cancer.

How can it be that courts are asked to decide cases based on science — while scientists themselves aren’t convinced?

“The courts are in a different business than scientists are,” said Mark Peterson, senior research scientist at the Rand Corp. in Santa Monica, Calif. “The court’s got somebody here who’s hurt now. So we can’t wait 20 years to wait for science to decide. You’ve got to decide a case now and you do the best you can.”

Judges and scientists may be asking the same question: Does this product cause this injury? But while science searches for conclusive answers — a quest that may take decades — the courts must make decisions based on the evidence they have before them today.

Meanwhile, it seems that month after month another product is taken into court by plaintiffs who claim it caused harm. There was asbestos, which has been shown to cause lung damage. And there was the Dalkon Shield contraceptive, linked to pelvic infections. Trials will begin soon on silicone breast implants, though the science is inconclusive.

“There are different amounts of truth that satisfy science and satisfy law,” said Stephen Teret, a lawyer and professor of health policy and management at the Johns Hopkins School of Hygiene and Public Health.

“The legal community has difficulty waiting for the scientific community to get a perfect answer,” said Francis E. McGovern, University of Alabama law professor who has served as a special master on mass-claim cases such as asbestos and silicone implants.

Lawyers for the plaintiffs in these suits say they do more than just compensate individuals. They say the trials often act as an early-warning system, alerting regulators to problems that must be corrected in the testing and marketing of drugs.

But some observers say that the effect of all these claims may be to discourage the development of new medical products.

“Something that is not very economical for society begins to happen,” said Georgetown University law professor Paul Rothstein.

“I think we are quite literally killing people because of a liability system that is not able to differentiate junk claims from good ones,” said Peter W. Huber, a fellow at the Manhattan Institute.

Breast implants case

The class action over silicone breast implants is an example of the controversy.

About 76,000 women around the country so far have joined in alleging that the implants can cause cancer, auto-immune disorders and connective tissue diseases.

To avoid massive litigation, manufacturers of the implants have created a $4.25 billion settlement fund.

But there’s no evidence widely accepted among scientists that the implants cause any medical problems.

In fact, the largest study of breast implants, published last month in the New England Journal of Medicine, found no evidence that they cause any serious diseases. The research was conducted at the Mayo Clinic in Minnesota, studying women who received implants from 1964 through 1991.

“The proof is not available in the epidemiology today,” said Michael Pretl, a Baltimore lawyer whose firm has also settled more than $40 million worth of claims involving the Dalkon Shield contraceptive.

Yet the implant cases are moving toward settlement — years before scientists are satisfied.

“If you have to wait until it’s accepted scientifically,” Mr. Pretl said, “well, some people would argue it’s still not accepted that cigarette smoke causes cancer. There are some people today who say there’s no evidence the Dalkon Shield causes infection. We say we have 150 studies to show there’s a link.”

There is other evidence that can be presented in court, Mr. Pretl said, which could include: manufacturers’ documents introduced at other trials; medical experts who can testify as to their observations; and patients who can recount their injuries.

Each side brings in experts, and the jury decides on their credibility.

“When the science is uncertain,” said Georgetown’s Mr. Rothstein, “the jury can make up its own mind, based upon how it assesses the credibility of the experts on the two sides.”

And if the jury reacts emotionally, perhaps awarding a settlement based on sentiment for the plaintiff rather than on the evidence, appeals courts are supposed to serve as a check on the lower court.

But companies are wary of long trials with the possibility of expensive verdicts. And that sometimes prompts large settlement offers.

“Juries don’t always get things right,” Mr. Huber said. “So there’s strong incentive to settle — even if you know science is on your side.

“A claim which would be laughed out of a court of scientists would not be laughed out of a court of nonscientists,” Mr. Huber said. “There’s no one-to-one correlation between what scientists believe and what courts do.”

In the class action concerning breast implants, the companies have offered to settle most of the suits, rather than watch tens of thousands of women go to court.

“For a fixed amount of money, they can get rid of the problem now,” said Mr. Peterson, at Rand. “Now they can confine and define the issue” by encouraging class-action settlements, thus limiting the risk of expensive jury awards later.

And the fact that the scientific evidence isn’t conclusive is not necessarily fatal to the claim.

“In trial,” said Dr. George Annas, professor of health law at Boston University, “all we want to know is: Who pays for this injury?”

Different standards

“There are important differences between the quest for truth in the courtroom and the quest for truth in the laboratory,” U.S. Supreme Court Justice Harry A. Blackmun said in a 1993 opinion in a case involving scientific evidence.

In a civil suit, the jury must be convinced by “a preponderance of the evidence,” something more than 50-50, that the injury was caused by the product.

But scientists hold themselves to a higher standard.

“Generally, the scientist has to convince himself or herself that something is going on here other than chance. The scientist looks for 95 percent certainty,” said Hopkin’s Mr. Teret.

“Law is not about pre-existing truths,” Mr. Teret said. “Law is something a bunch of guys made up. And if you think of the goal of a trial as the peaceful resolution of a dispute, then maybe you can have a peaceful resolution with 51 percent of the evidence.”

The Bendectin example

But does the system work?

Mr. Huber believes that drug companies are so wary of giant suits that innovation is stifled and insurance costs have risen wildly. Ultimately, the consumers pay — in higher prices to cover the manufacturers’ increased legal costs, he said.

But the public also may be deprived of a useful drug, he said, simply because the legal risks of marketing it are too great.

The example cited again and again is Bendectin, which was approved in 1956 for the treatment of morning sickness in pregnancy. The drug is no longer prescribed in the United States, — though studies found no direct link to birth defects and most plaintiffs lost their cases against the manufacturer.

When publicity over the first Bendectin suit, in 1977, prompted more claims, the Food and Drug Administration studied the drug anew. It found no conclusive evidence that Bendectin caused harm. And it said the drug should stay on the market.

But the number of lawsuits against the manufacturer surged. And despite the FDA’s findings in favor of the drug, the company stopped marketing Bendectin in 1983. The majority of cases against the drug were thrown out of court.

Professor Rothstein said, “I think our system does have some effect on suppressing drugs and on the other hand make us less competitive in world markets.” But he acknowledges that the system “does have some compensating benefits, in that people who might otherwise be wiped out [by medical damage] will be ” taken care of by society.”

But 10 years after it was taken off the market, Bendectin surfaced in a U.S. Supreme Court case last year. And the court’s ruling set new standards for what kind of scientific evidence is allowed before a jury.

In a case brought by two mothers who had used Bendectin before giving birth to children with defects, the court said that federal judges must assure that “any and all scientific testimony or evidence admitted is not only relevant, but reliable.”

That standard is far more flexible than the strict rules on scientific evidence that the court used since 1923. It means that judges can keep out unreliable “junk science,” but can let the jury hear from scientists who have new, reliable approaches to assessing links between products and injury.