IT WAS all so simple. Wendy Alexander had tied up Labour's Holyrood leadership without being challenged; it was a coronation rather than a contest. She succeeded Jack McConnell in September without breaking sweat. But the Paisley North MSP, ever the strategist, had a plan if she had faced a contest. Thus she set up the "Wendy Alexander Campaign" in August, a body to attract donations from supporters. Around £16,600 was raised in the end, cash that was used to fund a "tour" rather than a battle against a colleague.

Alexander's team is facing damaging charges that its members knew her campaign donation from tax exile Paul Green was suspect three weeks ago. According to her secret list of donors, of which the Sunday Herald has a hard copy, Green's cash was flagged up as being questionable as early as November 5. The document was created on a computer registered to "Brian Ashcroft", Alexander's husband.

This contradicts the claim made by Tom McCabe - Alexander's campaign manager - that she was made aware of a personal, rather than corporate, donation from Green last Thursday.

The meltdown of Alexander's leadership follows publication of two stories broken last month by this newspaper.

The first revealed how Alexander's leadership campaign had dodged declaration rules by attracting donations for £995 - a fiver less than the amount that needs to be registered.

This was followed by a second article, that outlined how the new Holyrood leader had accepted a donation from a tax exile living in the Channel Islands - a practice outlawed by her Labour colleagues at Westminster.

The reaction of David Whitton, a key Alexander ally and temporary press spokesman, was telling. He refused to deny the story, declined to name the tax exile, and instead stuck to the line that Electoral Commission rules had been "complied" with.

The story went nuclear last Thursday. The mystery tycoon was unmasked as Paul Green, a Jersey-based tycoon with business interests in the Isle of Man. Cash from such an individual, who is not entitled to vote in UK elections, is illegal under electoral law. The same day witnessed some of the most shambolic scenes ever seen at Holyrood. Whitton had tried to explain the donation by claiming it had been made by Green through a UK company, Combined Property Services (CPS). However, this was quickly denied by CPS managing director Gordon Wilson, who said Green was merely a "client" of his firm, which had not made any contribution to Alexander's campaign.

As news filtered out about CPS's non-donation, Alexander put in a shockingly bad performance at First Minister's Questions, followed by her getting chased down the stairs by a pack of journalists eager for answers. None were provided.

Whitton then found himself surrounded by the same media scrum, during which he failed to offer any explanation for Green's donation, or the CPS denial. The story was falling apart.

A press conference was arranged for 2pm, at which the media were told Labour MSP Charlie Gordon, the MSP who had organised the Green donation, would make a statement, followed by campaign manager McCabe.

Gordon told onlookers he had believed the Green donation was made through CPS, an assumption he now said was "wrong". He tendered his resignation as transport spokesman, and apologised to Alexander and Green.

The Glasgow Cathcart MSP's admission was followed by McCabe laying the blame at Gordon's feet.

However, the Sunday Herald has evidence in its possession that seriously challenges McCabe's claim that only Gordon knew of the tax exile's personal, and illegal, contribution.

Three of McCabe's comments give an appropriate context to the conspiracy to cover up Green's donation.

Asked at the press conference when Alexander first knew the donation had been made from Green, rather than CPS, he said: "Wendy always understood that money came from the company. When Mr Gordon explained to us the assumptions he had made at one o'clock today it was clear to us that a donation was not appropriate."

Asked on the BBC's Newsnight later about Green, McCabe said: "I couldn't have told you where he lived."

Asked by the Sunday Herald on November 17 whether Alexander had received a donation from a tax exile, he said: "That's the first I've heard of that."

However, the Sunday Herald has obtained a printed copy of Alexander's full list of secret donors, which names each contributor, how much was given, as well as the campaign member from whom it was solicited.

According to the "properties" tab in the Microsoft Word document, "Brian Ashcroft", Alexander's husband, is named as the "author". This means the document was created on a computer registered in his name.

The secret list, which has never been published before, states under the "donor" heading that Paul Green had made a donation of £950. No mention of CPS. The column marked "Name/ address for Elect Comm purpose" contained Green's Jersey address.

Crucially, the list also drew attention to the donation's illegality by stating at the end: "Permissible?" According to the word file on which it was saved, the document's date is November 5.

Days later, the Wendy Alexander Campaign informed the Electoral Commission that it had, in fact, received the donation from CPS. The details had been changed. Alexander's campaign team had information over three weeks ago that Green's donation was suspect.

At a time when there had been no press coverage of the subject, the team informed the Electoral Commission that the donation had come from CPS.

If the campaign had believed on November 5 that the Green donation was made through a UK-based company, why was the legality of the contribution questioned on its own list? And why was Green's Jersey address named as the contact detail?

Green's own interventions also implicate Alexander. He hit out at Labour for repeatedly dragging CPS into the mess, while making it clear that Alexander had sent him a letter to his Jersey address thanking him for the money.

In the light of such revelations, McCabe's insistence that Alexander, or anyone else, was only aware last week that the Green cash had come from him personally is open to question. A document created on Brian Ashcroft's computer suggests otherwise.

(Incidentally, the same list reveals a separate donation from a "PG other" for £995. The "banking section" column, however, states: "NO/REMOVE.") This is not the only "donor switching" row evident on the secret Labour list.

According to the Ashcroft document, one of the names in the "donor" section is Moir Lockhead, the chief executive of transport giant First Group, who was said to have contributed £995.

In the category marked "name/address for Elect Comm purpose", the name is switched from Lockhead to John Lyons, the former Labour MP. The cash, as stated on the list, was "on way via John Lyons". A spokesman for Lockhead denied he had made any contribution.

The bizarre "donor switching" is just one part of the campaign team's questionable fund-raising practices. Alexander's allies solicited donations that fell £5 under the level for public declaration, and made sure money was sent to the Campaign, not the MSP, to allow her to avoid registration at Holyrood.

As well as an Electoral Commission probe, Alexander could face a police inquiry after her team admitted to flouting the law. Pundits and MSPs are questioning whether the daily drip of revelations will make her Labour's shortest-serving leader.

During her leadership contest, Alexander spoke of her Labour "values" and called on colleagues to re-connect with voters. It is difficult to match her words with the deeds of taking cash from a tax exile, switching donors, and soliciting donations to avoid public disclosure.