Joe Wilson, who yelled "You lie!" during Obama address to Congress, is no Winston Churchhill

Joe Wilson uses presidential address as heckling opportunity. President Obama did not lose his cool.

"If we become accustomed to hearing people call a politician a liar everywhere else — for example, in town halls — suddenly it seems more natural in a place where it's never been acceptable," says Jamieson.

Heckling of president is rare in American history
By JOCELYN NOVECK (AP)
Sept. 11, 2009

...And then there was the 1838 pistol duel in which William Graves of Kentucky shot and killed fellow congressman Jonathan Cilley of Maine over words spoken on the House floor. (He wasn't even expelled.)

Given those breaches of congressional protocol, it would seem that a mere shout of "You lie!" from a 21st-century South Carolina congressman [Joe Wilson to President Obama during Obama's address to congress] would be small potatoes...

Yet there's little if any historical precedent for a U.S. congressman individually challenging a president during a speech to Congress — let alone accusing him of lying — which is just one reason why some longtime political observers were stunned by Rep. Joe Wilson's outburst...

"Occasionally, members of the opposing party have been known to boo and jeer as expressions of dissent on a specific point," says Beuttler, citing instances during the Bill Clinton and George W. Bush administrations. But before Wednesday, he says, "expressions of individual opposition of members to a president's speech had not been recorded."

Some have compared Wilson's outburst to those that occur routinely in Britain's House of Commons, when the prime minister is answering questions. But one political analyst says this is vastly different, because the prime minister isn't the head of state.

"Our president is the head of government and also the head of state, the combination of the country and the government," says Steven Cohen, professor of public administration at Columbia University. "We expect a certain amount of deference to the president, in the same way as we would for the queen. Here, we combine the two roles."

To another political analyst, it's the nature of the accusation — an elected official calling the president a liar — that is not only a serious breach (accusations of lying are forbidden under House rules) but also extremely rare in politics.

"Accusing someone of lying is impugning their integrity," says Kathleen Hall Jamieson, an expert on political communication at the Annenberg Public Policy Center at the University of Pennsylvania. "It was done in print a lot in the 19th century. But it is not routinely done in political discourse."

Congress is a place of deliberation, Jamieson adds: "If you call someone a liar, you've ended the deliberations. This is such a strong norm that it's been in the House rules since Jefferson."

...Winston Churchill was more subtle about the charge of lying, once describing a statement by another lawmaker as a "terminological inexactitude," now a commonly accepted euphemism for a lie...