THE Labour politician at the centre of allegations he threatened the career of a former colleague's disabled son during a crunch budget debate this week was previously investigated for inappropriate behaviour towards another female councillor.

Gilbert Davidson has been accused of using his role as a board member of the council-owned firm employing former Labour councillor Anne Marie Millar's son to strong-arm her into voting with former colleagues in what became a battle for the party's survival in Glasgow.

Mrs Millar, whose son Stephen has previously been an Apprentice of the Year and touted as Employee of the Year at City Building, said she believed the move was a clear attempt at threatening and intimidating her. The claims sparked pledges of an investigation by Labour.

It has led to calls for Scottish Labour leader Johann Lamont to condemn the "bullying and intimidation employed by the Labour group on Glasgow City Council" and to "take disciplinary action against those responsible".

However, it is not the first time Mr Davidson has been in the headlines for the wrong reasons.

Two years ago, The Herald revealed he had been arrested at his home after allegedly sending suggestive voice mails and text messages to former Glasgow Lord Provost Liz Cameron and asking her to share a hotel room with him during a local by-election.

The charges against the Springburn councillor, who was suspended by Labour during the investigation, were later dropped due to insufficient evidence.

Mr Davidson also faced allegations he groped ex-colleague Ruth Black, whose exit from Labour was confirmed yesterday, in the City Chambers in 2008.

In one of the more bizarre decisions at the council in recent years, Mr Davidson, whose reselection surprised many in the party, also chaired the committee that banned an advert for Reebok running shoes in the city because it featured the word "bum".

The committee that day also included Mrs Millar and fellow Labour councillors Tommy Morrison and Willie O'Rourke, all three of whom sided with the opposition in Thursday's vote.

The Herald understands many in the Labour group are furious Mr Davidson is embroiled in renewed controversy. One said: "He wouldn't have meant anything. People know what Gilbert's like. But he shouldn't have said anything to Anne Marie and certainly not mention anything about her family."

Another said: "It's pretty widely accepted Gilbert's got quite a chequered past and isn't the political world's biggest thinker. He's a pretty decent local councillor but speaks his mind too often and doesn't follow political niceties."

Despite the decision by several former Labour members to vote with the opposition, Labour had its budget passed by just two votes in the biggest threat to its authority in over 30 years.

But the SNP has seized on the bullying allegations and exits from Labour. In a notable move, local government minister Derek Mackay has made the unusual move of criticising a council his role requires him to work with.

He said: "In my role ministerial role I enjoy working with councils of varying political colours that are elected by people from all over Scotland but the scenes from yesterday inside the proud old building at George Square were embarrassing, and deeply damaging. Labour's position in Glasgow is now completely untenable."

In his letter to Ms Lamont, SNP MSP James Dornan said: "No-one who saw Councillor Millar yesterday could have been in any doubt she had been on the receiving end of some very unpleasant behaviour. She was visibly shaken and upset. Glasgow Labour was under pressure, but that is no excuse for this disgraceful behaviour. It is no way to run a council or a city."

A Labour spokesman said the party would look seriously at any claims of bullying.

The Herald called Mr Davidson but he hung up.