This article is the subject of a legal complaint from Derek Simpson and Unite

Derek Simpson and Tony Woodley, the joint general secretaries of Unite, were the butt of last year’s best political joke. “Look how far they’ve come,” Dave Prentis observed, sarcastically, of his fellow union bosses at the TUC’s annual conference in Brighton. “Only last year I said to Derek, ‘What would you do if you saw Tony staggering down the road?’ Derek replied, ‘Reload’. ”

Today Mr Simpson is the target of the latest volley in the most bloody union fight for decades. The fight has serious implications for Gordon Brown and the Labour Party.

It is not what Unite’s two million members were promised when Amicus and the Transport and General Workers’ Union merged on May 1, 2007. As a new dawn broke over that May Day, Mr Simpson declared that this was the beginning of a process that could lead to a global super-union.

“Right now we have this madhouse where we are all played off against each other. Until the unions can be structured internationally like the companies, we will always lose,” he told The Times.

Nearly two years on, the question of who – precisely – is running the asylum has never been more acute. No company that was the result of a merger would let both chief executives remain at the helm until they retired, but neither Mr Simpson nor Mr Woodley would agree to the merger unless allowed to stay on.

The agreement was that Mr Simpson would retire on his 66th birthday, December 23, 2010, and Mr Woodley a year later. The election of a single general secretary was supposed to take place next year, Mr Simpson’s last in office.

The period of co-rule started badly – and promptly got worse. Mr Simpson stayed away from Unite’s launch, offended that Mr Woodley had made a media appearance without telling him. There are few better symbols of the disharmony than the way that T&G and Amicus have been unable to move in together. While Amicus is in Covent Garden, the T&G is over a mile away at Transport House in Holborn. As observers never tire of pointing out, the two halves remain “in spitting distance” of one another.

Damaging stories about both men appeared to be the result of tit-for-tat briefings. It emerged, for example, that Mr Simpson had twice taken a helicopter to attend the Glastonbury Festival. Not long afterwards the arrangement of Mr Woodley’s grace-and-favour flat in London came under scrutiny. Mr Simpson’s purchase of a £50,000 painting by Antony Gormley for the Amicus headquarters found its way into print recently.

The manoeuvrings were sometimes farcical: at Labour’s conference both men were given cubicles – of equal size – behind the Unite stand because they literally could not bear to be in the same room.

When Mr Simpson likened some of Mr Woodley’s staff to “SS guards” and “cheerleaders in ra-ra skirts” it became clear that their relationship was heading for a breakdown.

The formal merger, due to take place last November, was put off. Mr Simpson was put on notice that he would face a legal challenge if he tried to stay in office beyond his 65th birthday.

To prevent Mr Woodley from seizing control after Mr Simpson’s forced departure next year, he has now put himself up for reelection as Amicus general secretary, a battle he is far from certain to win. Nowhere is the battle for control being watched more closely than at No 10. Not only is Amicus Labour’s most generous union donor, but Mr Simpson stuck with Mr Brown through the Prime Minister’s darkest hours last summer.

While Mr Woodley boycotted a crucial meeting of union leaders with Mr Brown, Mr Simpson stayed loyal. When David Miliband was about to open up a leadership challenge on the eve of Labour’s annual conference, it was Mr Simpson who launched a devastating attack on the young pretender, labelling him smug and arrogant – with a stream of epithets deemed too abusive to print by the newspaper that carried the interiew.

It came as little surprise to those in the know, therefore, when Mr Simpson hired Charlie Whelan, Mr Brown’s former spin-doctor, to become the union’s political director. “Anyone who believes you can write off Gordon Brown can think again,” Mr Whelan told a meeting during Labour’s conference.

“We’ve got an £8 million political fund. People need to know that a union can mobilise its members to support a candidate that the union likes.”

To the growing dismay of Labour MPs directly funded by Unite, most of the union’s energies are being spent on infighting. The level of mistrust in the union is graphically displayed in a recent e-mail sent by Mr Whelan to his staff. “You will need to let me know in advance when you are visiting the House of Commons and the purpose of your visit,” Mr Whelan wrote on January 6.

One of the e-mail’s recipients, Sarah Merrill, had already lodged a written complaint claiming that the political department under Mr Whelan had “a culture of fear and a climate of bullying”. Ms Merrill’s complaint went on to say that the atmosphere was “totally at odds with the policies of the union, and indeed is totally against the principles established under any dignity-at-work procedures.”

With little evidence of any dignity, many of the 111 Labour MPs sponsored by Unite are embarrassed at the damage being caused by the infighting when the party is desperate to reassure voters that it is focused on the effects of the recession.

Next month’s Amicus election is a two-way fight between Mr Simpson and Kevin Coyne, a northwest regional secretary.

Simpson on greed

‘We need action to protect jobs not just the huge shares and pensions that the executives secure for themselves’

Derek Simpson, 2008

‘The pay gap between workers and employers is astonishing, with average earnings rising by 4.5 per cent a year but 20 per cent per year for directors’ pay. City executive pay and bonuses would make Midas blush’

Derek Simpson, 2007

Woodley on greed

“London’s cleaners are fed up with fat-cat profits for the bosses while cleaners struggle to make ends meet”

Tony Woodley, 2007

“We live in a world where there is too often a race to the bottom in terms and conditions for workers, where the bad employer is able to undercut the good. A world of pensions robbery for those at the bottom and unbridled fat-cat greed at the top”

Tony Woodley, 2003

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