Ken behaving badly: the Mayor fights back

Ken Livingstone made it clear yesterday that he would defy his critics by standing for a second term as London's Mayor, despite a growing scandal that has led to police investigations into his actions at a party where a man ended up seriously injured.

The Mayor, who won his post with popular support dubbed the "taxi driver's vote", is planning to throw himself on the opinion of ordinary Londoners again.

"He has said he will leave it to Londoners to decide. He will stand again," said an ally of the Mayor.

With a deadline approaching to apply to rejoin the Labour Party, Mr Livingstone appears to have written off his chances of becoming the official Labour candidate. One leading London Labour MP described his chances now as "toast". But Mr Livingstone's popular support could evaporate as a result of the Scotland Yard inquiry into the claims by journalist Robin Hedges, 35, that Mr Livingstone lunged at him before he fell 15ft over a wall.

Friends of a defiant Mr Livingstone say he may refuse to attend a special hearing of the Greater London Authority on Wednesday, called by Trevor Phillips, the Labour chairman of the GLA, to answer charges that he lied about the incident.

Questions are now being raised about Mr Livingstone's fitness for office, and his critics are hoping that he will be suspended pending an investigation by the Standards Board of England.

The party, at which serious charges were raised about Mr Livingstone's behaviour, was thrown by Kate Beal, sister of the Mayor's partner Emma Beal. Mr Hedges refused to press charges, and the Mayor's office issued an unsigned statement by Mr Hedges dismissing his fall as an accident.

Mr Livingstone, against the advice of his aides, astonished GLA members last week when he volunteered a statement at a GLA meeting denying newspaper allegations that he was drunk and had been responsible for Mr Hedges' fall.

However, the next day Mr Hedges accused the Mayor's office of trying to cover up the incident when he gave his own account of it in the Evening Standard, for which he works. Scotland Yard this weekend confirmed it would be interviewing Mr Hedges about his allegations.

The Mayor's supporters accuse the Evening Standard of running a media vendetta against him and point out that Mr Hedges appears not to remember the moment when he says he may have been pushed, which would make it difficult for any allegations to stand up in court.

The Tories on the GLA have avoided attacking Mr Livingstone about his colourful private life but they are now scenting blood. Mr Livingstone could face claims he used GLA staff improperly to issue Mr Hedges' initial statement.

The Tories are also questioning whether the Mayor can fulfil his duties while the scandal continues. On Friday, the launch of the long-awaited London strategic plan by Mr Livingstone was reduced to a farce because of the row, as one protester chanted "GBH". Mr Livingstone cut short the press conference, saying he had to go to his partner's antenatal class. Next month, Mr Livingstone is due to host the opening by the Queen of the futuristic new Mayor's headquarters near Tower Bridge.