ST. LOUIS • A St. Louis jury delivered a defense verdict Thursday in a class-action suit that was seeking about $1.5 billion from tobacco giant Philip Morris.

The jury deliberated less than an hour after a month-long trial, in which the plaintiffs alleged the company had deceived customers into believing light cigarettes were safer than regular cigarettes when they weren’t.

The outcome would have affected Missouri smokers who bought and consumed Marlboro Lights from Feb. 14, 1995, through Dec. 31, 2003.

The class representative was Jefferson County resident Deborah Larsen, who smoked about a pack and a half of Marlboro Lights a day from 1979 until 2002, when she quit. In addition to the approximately $1.5 billion sought on behalf of the class, the plaintiffs’ lawyers had asked for about $6,800 for Larsen individually. They sought both actual and punitive damages.

This was the second time a St. Louis jury heard the case. In October 2011, jurors deliberated four days after another month-long trial before announcing they were deadlocked, 8-4, on the side of the plaintiff. Nine votes are needed for a civil case verdict in Missouri.

The lawsuit, first filed in 2000, claimed that light cigarette packages promised lower tar and nicotine but were made from the same tobacco as regular cigarettes, and were in fact more dangerous for consumers. Smokers might compensate for the lower nicotine by inhaling longer and more deeply, the plaintiffs’ attorneys claimed.

“They knew it was wrong … they knew they were deceiving people,” one of those attorneys, Mark Bronson, said in closing arguments earlier Thursday.

Jurors did not have to determine whether the class relied on the representations — just whether the deception occurred through “evil motive” or “reckless indifference to the rights of others.”

Philip Morris attorneys argued that the cigarettes are different, that they contain less tobacco than Marlboro Reds, more ventilation and a longer filter. Inhalation compensation also had been known and publicized for years by the public health community, the cigarette maker’s lawyers said.

Beth Wilkinson, an attorney for Philip Morris, noted the company took the label of “lower tar and nicotine” off packages in 2003 and eventually stopped using the term “lights” as well. No personal injury claims were included in the suit.

“Make no mistake, this case is only about money,” she said in closing arguments.

About 700 million packs of Marlboro Light cigarettes were sold in Missouri during the rough time period covered by the suit.