(CN) - The U.S. Supreme Court on Monday allowed Maine smokers to pursue a lawsuit accusing tobacco companies of violating state law by fraudulently advertising their "light" cigarettes as less harmful than regular brands.
The justices ruled 5-4 that federal law does not pre-empt the plaintiffs' claim under the Maine Unfair Trade Practices Act.
Smokers said tobacco companies touted their light cigarettes as containing less tar and nicotine than regular cigarettes, although studies showed the "lights" were as harmful to health - and possibly worse - than the regular brands.
A federal judge sided with the tobacco companies, ruling that the state-law claim was pre-empted by the Federal Cigarette Labeling and Advertising Act. The 1st Circuit in Boston revived the suit by overturning the district court's decision.
When Congress enacted the Labeling Act, it barred states from enforcing any rules about smoking and health that assumed the federal regulations were inadequate.
But the high court cited Cipollone v. Liggett Group, in which a plurality of Supreme Court justices allowed state-law claims that weren't based on smoking and health.
"The (Maine law) says nothing about either 'smoking' or 'health,'" Justice Stevens wrote, applying the earlier decision to the current case. "It is a general rule that creates a duty not to deceive."
The majority concluded that federal law "does not encompass the more general duty not to make fraudulent statements."
In dissent, Justice Thomas adopted Justice Scalia's criticism of the earlier plurality opinion, saying it created "an unworkable test for pre-emption with little or no relationship to the text of the statute."
Justice Stevens was joined by Justices Kennedy, Souter, Ginsburg and Breyer.
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