One of Chicago's best-known television anchors was found guilty today of libeling a cigarette maker for suggesting in a televised commentary that a Viceroy advertising campaign was aimed at encouraging children to smoke.

The verdict came after a five-day U.S. District Court trial in a $10 million libel suit by Brown & Williamson Tobacco Corp. against Walter Jacobson and CBS Inc., which owns and operates WBBM-TV, Jacobson's employer.

The six-person jury took less than three hours to decide the case. Jacobson, whose feisty "Perspective" commentaries have made him a top-rated Windy City personality, looked stunned by the verdict.

In a prepared statement, WBBM-TV called the verdict "incorrect" and said it will appeal, declaring it is "confident that, ultimately, the courts will completely vindicate Walter Jacosbon and CBS." Jacobson, 48, has been with the station 19 years.

The jury is to reconvene Monday to set damages.

Brown & Williamson sued after a November 1981 commentary in which Jacobson said Viceroy was planning an ad campaign aimed at children and equating smoking with "pot, wine, beer, sex and wearing a bra."

The company said the commentary was unjust and false. Brown & Williamson contended that it had rejected such an approach in 1975 and fired the ad agency that proposed it, and that Jacobson knew this when he broadcast his commentary.

Jacobson and his researchers denied defaming the company and testified that the commentary was based largely on a valid staff report by the Federal Trade Commission about cigarette advertising.

At one point, Jacobson testified, "I didn't say on television whether it was a current campaign. I had the FTC report and the evidence of my life experience, vague as it is, of seeing cigarettes passed out to children on the street. That's the kind of evidence I gathered."

Brown & Williamson attorney Martin London elicited testimony indicating Jacobson ignored a request from Michael Radutsky, then his chief researcher, to mention a disclaimer from the cigarette maker saying it had never launched the ad campaign in question.

Radutsky, now producer of the station's late-night news show, conceded under questioning by London that after the suit was filed he threw out materials he used in preparing the commentary.

He said he had not known of a longstanding CBS policy that all materials relating to a libel suit should be preserved. He said CBS lawyers didn't tell him that the suit, once dismissed, had been reactivated on an appeal.

Radutsky also admitted telling Jacobson that he had obtained secret, internal Brown & Williamson documents outlining the alleged ad campaign when, in fact, Radutsky had obtained that information from an article in a Kentucky newspaper.

WBBM-TV complained that the trial judge, William T. Hart, refused to allow the author of the FTC report to testify.

Jacobson said after the trial, "The cigarette companies are out to stop us from reporting."