The US Supreme Court ruled in a five-four decision that three long-term smokers from Maine had the right to sue Altria Group, the owner of Philip Morris, which manufactures Marlboro Lights, over fraud.
Citing the Maine Unfair Trade Practices Act, they were seeking compensation for economic rather than medical harm as they allege that they had overpaid for cigarettes based on deceptive ads suggesting that "light" cigarettes were safer than regular ones.
Smokers ended up buying more cigarettes as many tended to smoke lighter cigarettes more quickly.
The smokers, who acknowledged that the "light" brands did have less tar and nicotine, argued that Altria knew smokers compensated for the decreased potency by holding smoke in their lungs for longer or by covering the filter ventilation holes with their fingers.
The question before the court was not whether use of the term "light" amounted to fraud, but rather whether the smokers should be allowed to sue at all given the federal Cigarette Labelling Act, which requires that every pack of cigarettes sold in the US contains a "conspicuous warning".
Justice John Paul Stevens ruled that "respondents still must prove that petitioners' use of 'light' and 'lowered tar' descriptors in fact violated the state deceptive practices statute, but neither the labelling act nor the FTC's actions in the field prevent a jury from considering that claim".
Therefore, the three smokers are allowed to proceed with their law suit, which will be heard in a district court.
Murray Garnick, associate general counsel and client-services senior vice-president for Altria, said in a statement: "While we had hoped for a dismissal based upon federal pre-emption, it is important to note that the Supreme Court made no finding of liability.
"We continue to view these cases as manageable, and the company will assert many of the strong defences used by successfully in the past to defend against this very type of case."