The farmers wanted $11m damages from Ms Winfrey over the plunge in beef prices which followed her comments about the risks from BSE.
But a jury in Amarillo, Texas, ruled in favour of the talk-show host.
To cheers from her supporters outside the court, Ms Winfrey declared: "Free speech not only lives ... it rocks.
"I have come from people who have struggled and died to have a voice in this country and I refuse to be muzzled."
![[ image: width=150]](/olmedia/60000/images/_60443_op.jpg)
"What the witness stand is designed to do is take your self away from you. You are literally faced with people who are telling you, 'You are not who you say you are'.
"You really have to hold on to your own sense of power and your own sense of self-worth."
She said she had received threats from people in the area before the trial.
"We were frightened physically and emotionally. But I have a very strong faith and we were protected. I did not know I would have this kind of support
After the verdict, cattle rancher Paul Engler said: "I think we needed to get the facts out in so far as the safety of US beef and we did that."
In her show, guest Howard Lyman had said American cows were fed with meat from their own species.
He told Ms Winfrey that scientists had identified this practice as the cause of the BSE outbreak in the United Kingdom.
The host asked the crowd: "Now doesn't that concern you all a little bit, right here, learning that? It has just stopped me cold from eating another burger."
Within seconds, beef prices in American markets had started to plummet.
![[ image: width=150]](/olmedia/60000/images/_60443_oprahfront.jpg)
Ms Winfrey's lawyers argued that she was merely seeking to draw her audience's attention to a potential threat.
After five hours deliberation, the jury of eight women and four men backed her case.
Inside the packed courtroom, the verdict was met with shouts of support.
US District Judge Mary Lou Robinson last week threw out claims of a food disparagement libel.
She ruled that the suit would be tried solely on business disparagement law, which meant that the cattle ranchers would have had to prove malice on the part of Ms Winfrey.
Two-tier BSE system agreed
(25 Feb 98 | World)
Oprah food libel claim rejected
(18 Feb 98 | World)
Jury selected in Oprah Winfrey trial
(21 Jan 98 | World)
Oprah Winfrey faces mad cow libel suit
(20 Jan 98 | World)
The Oprah Winfrey Show
Information on BSE
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