Curse of the open mic

Britney Spears, George W Bush and John Major have all reportedly been caught unawares by open mics - the new nightmare for those in the public eye.

The words "open microphone" are enough to freeze the blood of politicians, celebrities and others in the public eye.

The phrase is media jargon for a microphone left on by a journalist or technician before an interview or performance has started, or after it's over.

"Is this thing on?"

The celeb relaxes and starts blurting out what he or she really thinks - often punctuated with a welter of swear words.

Pop sensation Britney Spears is reported to be the latest victim. In a fluster before going on stage in front of her biggest ever live audience in Rio de Janiero, Britney apparently began lambasting her entourage.

"Don't tell me that they're just letting the audience just f****** stand out there like that. Oh my God! This is retarded."

Every word was transmitted live to the 170,000 concertgoers and then relayed around the world; her record company maintains it was someone else's voice heard.

Careless whispers

During the US presidential campaign, George W Bush experienced a similar problem.

"Smile, I think they can hear us"

Just before a campaign speech, the candidate complained about New York Times reporter Adam Clymer, calling him "a major league asshole".

At the time, the sudden revelation that the would-be president was not only capable of harbouring a major grudge, but could swear with the best of them looked like it could have lost him the election.

The most celebrated instance of British open mic syndrome was the 1993 performance of Prime Minister John Major.

After an interview with then ITN political editor Michael Brunson, Mr Major let fly, seeming to forget that he was in a studio bristling with every imaginable type of recording equipment.

"Mind what you say, John"

He castigated members of his cabinet as "b*******", promised to "crucify" them, and confessed that he was a "wimp" who had no idea how to win an election.

Mr Major, under pressure because his "back to basics" campaign had been destroyed by tabloid revelations of backbenchers' indiscretions, was caught moaning that: "I can't stop people sleeping with other people if they ought not to."

Some commentators said the leaked tape did Mr Major a lot of good as it showed him to be "an ordinary bloke".

Testing, testing

"I know what'll make 'em laugh..."

The same was said of former US President Ronald Reagan. Just before making a radio broadcast at the height of the Cold War in 1984, he said: "I am pleased to tell you I just signed legislation which outlaws Russia forever - the bombing begins in five minutes."

Only later did he find out that the mike was already on.

The advent of satellite TV "feeds" present new dangers for the gaffe-prone politician.

It is now common practice for US politicians to give dozens of interviews in a Washington studio, which are then relayed via satellite to local TV stations around the US, one by one.

During the 1992 presidential campaign which brought Bill Clinton to power, American media-watcher Brian Springer recorded 500 hours of these feeds.

Private asides made public

The material, which Mr Springer made into the documentary Spin, showed politicians like George Bush Snr, his wife Barbara and Mr Clinton simply staring into the camera - sometimes combing their hair or scratching their nose - between hook-ups.

Journalists - and spin doctors - watch every word

One of the "feeds" showed Mr Bush discussing his heart drugs and sleeping pills with interviewer Larry King.

"My brother is in the pharmaceutical business," King whispered to the then president. "He says there is a pill coming from Israel better than Halcion."

"You mean sleeping pill or decongestant?" Mr Bush asked. The interviewer mumbled that it was a strong sleeping pill. "Great," came the reply.

Media advisors and consultants now routinely warn those in the public eye to "treat every microphone as though it is live".

The warning may do something to reduce the number of gaffes.

But it can't protect them from the consequences of what they say when they are fully aware that everyone is listening.