Law has increasingly become politics by other means.

Those defeated at the polls go to court for another turn at bat — even private negligence lawsuits have become another kind of government welfare program.

That’s why President Clinton recently attended a fund-raising dinner hosted by Stanley Chesley, a wealthy tort attorney who handled one of the lawsuits against the tobacco companies. For both Clinton and Chesley, law and politics are one.

The result of this merger has been to transform traditional liability law. Many juries now view sympathy, not fault, as the legal standard. They impose liability on the deepest pocket around irrespective of the evidence.

This trend has encouraged creative lawyers to find new parties to blame — like a company’s board of directors for falling stock prices.

Attorneys have persuaded juries to hand cash to plaintiffs who were responsible for their own injuries, like the drunk who stumbled in front of a New York City subway train. Irresponsible verdicts like this one cause many defendants to settle out fear, as did the California education district sued by the would-be burglar who fell through a school skylight.

Even state governments got into the game,’ suing tobacco companies for the cost of treating people who chose to smoke. And juries awarded perceived victims with grossly excessive awards, like millions of dollars for a mispainted BMW. Even more dangerous has been the rise of junk science — claims of causation and harm built on evidence of sand. Of course, the courts have never been free of fraudulent claims. Attorneys once won suits claiming that bumps from falls caused cancer.

With the assistance of their political friends, attorneys like Stanley Chesley have turned liability litigation into a massive lottery, in which neither injury nor fault needs be shown for huge prizes to he won.

However, junk science has now reached epidemic proportions, with massive class actions revolving around asbestos, electromagnetic fields, multiple chemical sensitivity and silicone breast implants.

Many (though not all) of the plaintiffs in such cases are hurting. But virtually all scientific authorities agree, not for the reasons charged — like living near a power line.

The facts haven’t stopped profit-minded lawyers from finding dubious experts to propound equally dubious theories, however. In some cases advocates are presenting “what is charitably called an educated guess,” observes Marcia Angell, executive editor of The New England Journal of Medicine. In other instances the purported experts are simply lying.

Helping juries’ and judges navigate the many fraudulent shoals in the evidentiary stream has become an increasingly important issue. In the 1993 case of Daubert v. Merrell Dow Pharmaceuticals, in wlich the plaintiffs blamed the drug Bendectin for their children’s birth defects, the Supreme Court unanimously ruled that the trial judge was to ensure that all “evidence admitted is not only relevant, but reliable.” That requires “a grounding in the methods and procedures of science.”

Since then, federal judges have become more willing to challenge idiosyncratic arguments and theories. Some jurists have tapped neutral scientists to help assess professional literature and evaluate trial testimony, a procedure endorsed in February by Supreme Court Justice Stephen Breyer in a speech to the American Association for the Advancement of Science.

In fact, the AAAS, which has long been concerned about the manipulation of science, is developing .a pilot program to help make independent experts available to interested judges.

However, most trials occur at the state level. The problem of runaway litigation will persist until state judges also screen junk science out of their courtrooms.

That process, too, may have begun. Just days after Justice Breyer’s speech, New Mexico Judge W. Daniel Schneider applied Daubert to exclude testimony in four breast implant cases. Schneider explained that the evidence, including testimony from the notorious Pierre Blais, who has traveled the world promoting breast implant litigation, was “not reliable.”

Schneider added: “The theories advanced by the plaintiffs’ experts have not been tested, nor subjected to peer review or publication. With no testing, it is virtually impossible to determine any rate of error. The testing that has been done in the area does not support plaintiffs’ experts’ theories. Their theories are currently not accepted as valid in the medical community. Lastly, their theories are not capable of supporting opinions based upon reasonable probability.”

Judges who fail to act as gatekeepers to block this sort of junk science are failing in their responsibilities. Warns Schneider, accepting any and every claim will leave “a lay jury to base their decision on speculation, guess or conjecture.” That might be fine for a dinner conversation. It should not be the basis of a legal verdict.

With the assistance of their political friends, attorneys like Stanley Chesley have turned liability litigation into a massive lottery, in which neither injury nor fault needs be shown for huge prizes to he won. Judges and legislators alike need to reform the system. The former are starting to act; now it is the lawmakers’ turn.