Unite in the dock

Unite, the party's biggest trades union affiliate, decided that the Labour vacancy in the selection would be filled by one of its own. The chosen one was Karie Murphy, who as well as being an aide to senior MP Tom Watson is a close ally of Unite general secretary Len McCluskey.

What followed in autumn 2012 was a co-ordinated attempt by Unite to take over the Falkirk West constituency party, with the sole aim of installing Murphy as Labour's candidate.

The strategy was funded by the union and implemented locally by various figures including Stevie Deans, who was both Unite's Scottish chair and the union convener at the nearby Ineos plant at Grangemouth. Over a number of months, the union channelled resources into the seat and Unite-friendly individuals took key posts on the local party's executive.

More controversially, Unite recruited over 100 new members in a blatant attempt to help Murphy, who had no roots in Falkirk. Many of the new sign-ups were linked to the Ineos plant and recruited by Deans, with the membership fees paid by Unite. By January, the strategy was on course. Deans was in the influential position of constituency party chair, Unite money was working to good effect, and many of the new applications had been processed.

A Murphy win was almost a fait accompli.

However, by the end of January, the Sunday Herald learned of misgivings in the local party about Unite's aggressive strategy. When this newspaper informed Murphy of our intention to run a story on her bid to become the Labour candidate for Falkirk, lawyers from London-based Mishcon de Reya contacted us on her behalf.

The firm, which represented Princess Diana during her divorce, said its "client" would consider legal action if certain points were not changed or clarified. We later published the first of nearly 30 articles on the saga.

As tensions grew, Unite pushed ahead with its strategy of getting Murphy selected. The union helpfully paid the postage on a "survey" on whether an all-woman shortlist should be used in Falkirk, an outcome that would knock out Gregor Poynton, who along with Councillor Linda Gow was another of the three contenders. Funding the survey was in spite of Unite's traditional scepticism towards such shortlists.

However, by spring, complaints about Unite's alleged activities were beginning to prick the conscience of the UK party. A Labour troubleshooter was sent north and demanded that all the new recruits fill in direct debit forms if they wanted a vote in the selection. By May, the concerns were so strong that Labour suspended the contest and launched a probe.

This newspaper then revealed the key allegation at the heart of the scandal: Labour was investigating toxic claims Unite had signed up members without their consent. By July, all hell broke loose.

Upon completion of the investigation, Labour leader Ed Miliband said new members had been "signed up without their knowledge", and hit out at "bad practice" and "malpractice" in Falkirk. Murphy and Deans were suspended from the party, the scheme that allowed Unite to recruit the members was scrapped, the local constituency party was put into "special measures", and the police called in.

Prime Minister David Cameron also savaged Miliband over the row, portraying the Labour leader as a puppet on McCluskey's string. McCluskey, while insisting that his union had done nothing wrong, admitted the perception was bad: "I recognise that the perception is in Falkirk that we have moved to buy votes in the constituency ... It is false, but perceptions matter."

However, just as Labour believed it had cleaned up Falkirk, Unite mounted a comeback. The union hired a legal firm to take up the case and examine what Unite believed was a flimsy and unfair investigation by Labour. Some of the original allegations that had triggered the suspensions were then mysteriously withdrawn.

The case against Deans and Murphy collapsed and Unite was jubilant. However, at the point when Unite believed it had won a famous victory, the row entered another phase. It was claimed that Deans, whose day job was representing the workforce at the Grangemouth plant, had been using company time and resources to plot Murphy's selection. When Ineos put him through internal disciplinary procedures, Unite threatened a strike and set in train a series of events that led to the near closure of the entire plant.

Hours before a showdown meeting with his employer, Deans quit, and hundreds of Labour-related emails were leaked to a Sunday newspaper.

They showed that lawyers acting for Unite had met a key witness at the centre of the original allegations; and that the union may have had a hand in producing the affidavit that was the basis of the withdrawn evidence.

According to Unite's accusers, the union had interfered with Labour's investigation into Deans and Murphy. The police were called back in, while a complaint was also made to the Information Commissioner.

Ten months on from this newspaper's first story, the ramifications of the scandal are astonishing. For Labour, the local party in Falkirk is still in "special measures" and all three original contenders for the selection have been knocked out of the race.

Johann Lamont, the Scottish Labour leader who for bizarre constitutional reasons has been almost a bystander, has been criticised for her slowness to speak out. More significantly, Miliband has used the Falkirk fiasco to back far-reaching change to the historic link between his party and the unions.

The row has also provided Cameron with a key theme for the next general election - namely, Miliband's relationship with the super-union. However, while Miliband has used the row as an opportunity for reform, the events have been a disaster for Unite.

In January, Murphy was set to win the selection and the union was an influential presence at the Grangemouth plant.

Murphy's Westminster ambitions are dead and Unite has been outmanoeuvred by Ineos as a result of Deans's activities.

Deans himself is out of a job and Unite's handling of the Grangemouth row is considered to be a textbook case of how not to conduct industrial relations.

The union also appears to be the butt of Labour movement jokes. "I heard Unite had to cancel their nativity events in Falkirk this year. They couldn't find three wise men," said one wag.

Many lessons will drawn from the Falkirk selection, but the shambolic episode is likely to be seen as the occasion when Unite snatched humiliation from the jaws of victory.