Tribune confirmed this morning that it has been served notice that Jackson is taking legal action against the newspaper, following comments in the paper attributed to Amicus official Derek Simpson.
Simpson, who is expected to challenge Jackson for his post at the union, was quoted in the February 15 issue of Tribune where he made several allegations, which for legal reasons can not be repeated.
The magazine published an agreed unreserved apology to Sir Ken in the March 8 edition, withdrawing the remarks and disassociating the paper from the implication that Sir Ken condoned corruption. It accepted that any such suggestion was without foundation.
The title also apologised to Simpson in the same issue for misrepresenting his remarks. The apology said that Simpson never used the phrase attributed to him by Tribune.
Sir Ken is now claiming that the apology to Simpson, which ran immediately underneath the apology to Sir Ken, devalued the apology to him and that because of that he was proceeding with legal action.
The paper refused to comment further on what its next move would be. However, in an earlier interview with the Independent, Tribune editor Mark Seddon said: "Sir Ken is a reasonable man and I was hoping to settle this dispute privately."
Another source at Tribune said that if the title was ordered to pay damages it would be forced to close. "We haven't got any money, it is as simple as that," the source said.
One option open to the magazine would be to mount a financial appeal to its readers.
Tribune is 65 years old on Saturday and can list names such as writer George Orwell and NHS founder Aneurin Bevan among its contributors. Former Labour leader Michael Foot is a former editor and one of its directors.
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