NEWARK, MARCH 3 -- A government scientist challenged the cigarette industry in a smoker-death trial today by calling tobacco a dependency-creating drug and saying prolonged use impairs the freedom of choice of smokers to continue or discontinue the habit.

In turn, a defense lawyer tried to undermine the credibility of Dr. Jerome H. Jaffe, director of the Addiction Research Center in Baltimore, a unit of the National Institute on Drug Abuse.

The smoker, Rose D. Cipollone, who died in 1984 at age 59, became "heavily dependent" after starting to use cigarettes at 16, said Jaffe, who had interviewed her for more than an hour in her lawyer's office.

"It is not easy to stop -- that's the nature of dependency," said Jaffe, a psychiatrist who testified as an independent expert -- not representing the government -- for Mrs. Cipollone's husband. To show the dependency of Mrs. Cipollone, who smoked for about 40 years, he cited numerous "markers."

For example, she smoked even after surgeons removed part of her cancerous right lung three years before her death, Jaffee said. When guests used up her cigarettes, she retrieved butts from the trash. In the morning, she would light up before brushing her teeth and washing her face.

During the interview, Jaffe said, Mrs. Cipollone told him of a time when, in trying to quit smoking, she had to give up drinking coffee and watching television. She said these activities had become strong psychological cues to smoke because she had always lighted up when she engaged in them.

Jaffe said Mrs. Cipollone had a physical dependency on tobacco, which he defined as a need -- varying in degree with individual circumstances -- to continue drug use to avert withdrawal symptoms. Physical dependence can be, but is not necessarily, part of overall drug dependence, Jaffe testified.

He agreed with the defense argument that like other smokers, Mrs. Cipollone smoked for pleasure. But, he said, some drugs are taken up for enjoyment, and enjoyment and dependency are entirely compatible. He also agreed that tens of millions of smokers have quit, but cited studies showing that perhaps 80 percent resume smoking within a year.

Jaffe was cross-examined for more than three hours by James V. Kearney, an attorney for Liggett Group, who will resume his questioning Monday.

Charles R. Wall, a spokesman for Liggett's codefendants, Philip Morris Inc. and P. Lorillard Inc., told reporters that Kearney was trying to show that Jaffe "has no objective standards by which to measure dependence."Rather, Wall said, Jaffe assumes a person who exhibits withdrawal symptoms, and who smokes, is dependent. "Those symptoms occur on cessation of many activities," such as consuming caffeine and chocolate, Wall said.

In this regard, Jaffe said the power of nicotine in sustained use to create dependency is incomparably greater than that of chocolate or caffeine.

He told the plaintiff's attorney, Marc Z. Edell, that he agreed with Philip Morris scientists, whose internal papers have been put in evidence.

One of the scientists called nicotine "a powerful pharmacological agent {that} may be the most important component of cigarette smoke." Another wrote that "in concentration camps of World War II, the incentive value of the cigarette exceeds that of essential foodstuff."

Jaffe acknowledged to Kearney that in the interview, Mrs. Cipollone hadn't told him that she had had a car accident that resulted in symptoms like those he and she attributed to smoking cessation, that she had been in psychotherapy and on antianxiety drugs, and that he had not reviewed her medical history.