LAST TUESDAY'S GATHERING OF SCOTTISH MPs at Westminster could not have been mistaken for a meeting of the Wendy Alexander fan club. "We were fizzing with her," said one Labour MP. "We were totally hacked off not to be consulted."

Another MP said: "She is being called the leader of the Labour party in Scotland, when she is no such thing. She is the leader of Labour at Holyrood. For now."

The reason for the Labour MPs' anger was Alexander's unilateral decision to support a referendum on independence, a strategy designed to defeat the SNP government's top priority by facing it head on.

Labour's week of turmoil began last weekend, when an article in the Sunday Mail suggested Alexander and Prime Minister Gordon Brown, her mentor, were ready to change their position and back a referendum.

Alexander's aides insist the story was not sourced by them, but suspect it was planted by a senior trade unionist with strong links to the Labour government.

The smoking-out of Labour's private discussions left Alexander with a tough choice as she faced a pre-prepared television interview on the BBC's Politics Show last Sunday: either downplay the story, or admit its veracity.

Her decision to confirm "tactical discussions" and back an early referendum -"Bring it on" - may have been a bold political manoeuvre, but it was not cleared by anybody in advance.

Her U-turn, one of Scottish Labour's biggest constitutional gambles in its history, was made without the knowledge of her shadow cabinet, the party executive, Downing Street or even her own advisers.

Alexander's comments have also had the effect of setting in train some of the most chaotic and confusing scenes within Scottish Labour for decades.

The key to understanding the farce of last week rests in knowing the content of the conversations between Alexander and the prime minister.

According to Alexander's aides, she and Gordon Brown spoke to each other about the referendum position every day from Sunday onwards.

Her belief, say the MSP's allies, was that Brown was content with her new policy, even if he was puzzled at how it had been announced.

Alexander, who believed she had Brown onside as a result of the conversations, went further on Monday by giving details of how she would like a referendum to proceed. "I am very attracted to the idea of a straight choice for or against independence, which Alex Salmond says he is in favour of." She also wanted the poll before 2010, the SNP government's favoured date.

Twenty-four hours later, Labour at Holyrood backed Alexander. "We will not vote down any referendum bill that comes to the parliament," said party group convenor Duncan McNeil in what was a significant strengthening of the position.

This was followed by Alexander chairing her own press conference, at which she elaborated further on her new big idea. Labour could, she said, bring forward its own referendum bill before 2010. She also reiterated her support for a poll to settle the question of independence.

"I will not lead Scottish Labour into the lobbies to vote down the right of the Scottish people to speak," she said.

She went even further in an interview that evening on Newsnight Scotland. Asked whether the prime minister supported her stance on the referendum, she said "Yes".

But by the next morning her story had begun to unravel. An article in the Daily Mirror, whose Westminster journalists have strong links to Downing Street, claimed Brown had been "taken aback" by Alexander's policy shift.

This confirmed speculation from the previous day that Alexander had bounced Brown into the referendum policy, thus putting him in an impossible position.

By the time of prime minister's questions on Wednesday, it was clear that Brown had two sensible options open to him: reiterate his spokesman's statement that Alexander's position was a matter for her, or back her.

The ailing prime minister, however, opted for a third way by bizarrely denying that Alexander had ever supported a referendum.

"That is not what she said," Brown told a bemused David Cameron, who had asked the prime minister if he agreed with his Scottish colleague's position.

Brown also contradicted Alexander's call for an early poll by saying that no decision on further constitutional change would be made until after the Calman Commission, set up to review devolution, presents its report next year.

His response, described by one of his own MPs as "bizarre", created an immediate split and sent Team Alexander into a panic.

Alexander's advisers - including MSP Jackie Baillie, deputy leader Cathy Jamieson, spin doctor Simon Pia and director of research and strategy Sarah Metcalfe - decamped into Labour's "emergency room" at Holyrood and cobbled together a statement.

The final draft ignored Brown's snub and instead stated that the pair were united in "exposing the hollowness of the SNP's position", whatever that meant.

The shambles led to Pia, who is said to have brought a calming influence to Alexander's office, being slaughtered by the press on Wednesday afternoon.

Asked to explain Brown's lack of support for Alexander, he said: "I'm not here to speak on behalf of Gordon Brown."

On whether Alexander was happy about the way Brown had dealt with the independence question at PMQs, he said: "I haven't asked her."

And probed about the unattributed criticisms emanating from Downing Street, he said ironically: "Some of these spin doctors are dodgy types."

An awful day for Alexander then got worse when it emerged that her idea for a Labour referendum bill would breach the parliament's standing orders. Thursday only added to the confusion. Alexander again defied Brown by saying she wanted an early referendum, while her aides appeared to retreat from Tuesday's position by refusing to endorse McNeil's view that Labour would not vote down any referendum.

She, too, appeared to backtrack around lunchtime. "No blank cheques," she said about her support for the SNP's referendum, which was different to "bring it on" from four days earlier.

Even senior party figures who support Alexander's leadership are critical of what she has done.

Former education minister Sam Galbraith said: "I am not in favour of a referendum: it will solve nothing."

Labour MSP George Foulkes, who backs the idea for a referendum, said: "The mistake was the lack of timing and lack of consultation."

Her brother Douglas Alexander, the secretary of state for international development, supports Gordon Brown rather than his sister. "I am a member of the cabinet. I support the government's position," he said.

One veteran said the Paisley North MSP, had she "any sort of political brain", would have announced a review of the Scottish Labour's referendum policy last year and then announced the change at the party conference.

Instead, her critics say, she made policy on the hoof without informing anybody and claimed Gordon Brown supported her when it was unclear whether or not he backed the shift.

Alexander's aides, in contrast, accuse Brown of reneging on a deal made in private and criticise his "inept" handling of prime minister's questions.

A source close to Alexander said: "The problem is that Gordon's a ditherer. He could have been a lot more helpful than he has been."

Another friend of Labour's Holyrood leader said of Brown's advisers: "They just don't give a f*** about Scotland. All they care about is the next general election."

A policy change that could have united the party has, in the words of one insider, "turned into a shambles".

Alexander's leadership, far from leading to the promised "reform, renewal and reconnection", appears to have reaped division, disaster and disconnection.