In the wake of the Arizona shooting, experts on media and societal response to rhetoric say it is important to remember the impact violent and extreme commentary can have.

Although it is unclear what motivated alleged gunman Jared Loughner prior to the Jan. 8 shootings in Tucson, observers warned that violent media rhetoric has the potential to lead to very real violent results.

Nathaniel Cordova, associate professor in rhetoric and media studies, at Willamette University in Salem, Oregon, said the impact of harsh language in the media is clear:

“Violent rhetoric from the media has a powerful effect, it sets a tone, sets an agenda. Discourse does not have to directly say, 'Let's do this to harm this' it just has to set an agenda to frame issues in a way that legitimizes a certain course of action,” he said. “Fox News has been particularly horrible at this, they have been for a long time peddling a cultural war and they rely on pushing that political discourse.”

Media Matters has reported on several recent instances in which violent acts or threatened actions were linked, in some way, to angry media messages.

*Alleged gunman Byron Williams admitted last fall he had been influenced by a Glenn Beck program when he set out to attack members of the Tides Foundation in San Francisco and got into a gun fight with police.

Three psychiatrists who spoke with Media Matters after viewing a clip of Beck's program that Williams had said he viewed prior to the shooting voiced concern that it could have a negative effect on viewers.

“I could imagine that for a section of the population looking for a consensus to confirm their own suspicions of government in general, this is good fodder for them,” Psychiatrist Steven Levine of Princeton, N.J., said at the time. “Because of his style, for those who are less inclined to be naturally skeptical, who are looking for someone to support their views, it adds fuel to the fire.”

*Charles Wilson, who was convicted in October after threatening Sen. Patty Murray, was “under the spell that Glenn Beck cast,” according to a relative.

*Gregory Lee Giusti was sentenced to a year and nine months in federal prison in December for threatening to destroy former House Speaker Nancy Pelosi's home if she voted in support of health care reform.

His mother told a San Francisco television station that Fox News was a factor in his actions: “Greg has -- frequently gets in with a group of people that have really radical ideas and that are not consistent with myself or the rest of the family and -- which gets him into problems. And apparently I would say this must be another one that somehow he's gotten onto either by -- I'd say Fox News or all of those that are really radical, and he -- that's where he comes from.”

“There is plenty of reason why our politicians and media do our nation a disservice with ugly rhetoric,” said Joel Dvoskin, PhD, assistant clinical professor of psychiatry at the University of Arizona college of medicine, later adding, “What is on television influences behavior.”

In a recent Q&A for the American Psychological Association on the Arizona shooting, he had also said: “There is a great deal of research suggesting that the media people consume influences their behavior, including violence and aggression.” Asked about this statement, he confirmed it, but added: “The saturation publicity and the dramatized national coverage across all media of these events increases the likelihood of these events, generally.”

Martin Medhurst, distinguished professor of rhetoric and communication at Baylor University, said such rhetoric can affect those who are mentally imbalanced:

“It creates a climate, a rhetorical climate that may be more conducive to people who are not able to balance messages that they hear. The mind of a disturbed person, anything can affect it. They react differently to all messages.”

Robert M. Entman, a professor of media and public affairs at George Washington University, said the danger of harsh rhetoric becomes worse when other news outlets give Fox News credibility after it offers such comments.

“Obviously Fox and Limbaugh, etc., are acting irresponsibly,” he said. “But when the other media treat Fox News as the right-wing equivalent of MSNBC, and therefore as a legitimate journalistic organization, they are encouraging Fox and legitimizing Fox and even legitimizing Fox in the eyes of some of these crazy people.”

Douglas Kellner, a professor in the Graduate School of Education & Information Studies at UCLA and the author of several studies on media's impact on society, cited the use by some media commentators of firearms imagery, such as Sarah Palin's infamous map marked with crosshairs and her instructions to “RELOAD!”

“There is no question that these violent gun metaphors can trigger violent episodes, it is basically a command and enticement to act,” he told Media Matters.

“People like Glenn Beck and Sarah Palin thrive in this kind of atmosphere because they are [portrayed as] victims and the people they appeal to see themselves as being victims,” said Andrew Rojecki, professor of communication at the University of Illinois, Chicago and author of several media behavior studies. “People are angry and scared and very insecure about the country's economic position and their future.”