Mitt Romney denies he lied under oath to protect friend in divorce settlement

Romney is believed to have testified that Staples was in trouble with its shares worth under $2

Lawyer Gloria Allred talks with reporters outside the court in Massachusetts yesterday (Reuters)

Mitt Romney's testimony in a decades-old divorce case was at the centre of a fresh bout of electoral mudslinging last night, after a judge ordered a previously-sealed transcript of his contribution to the trial to be released to the media.

The Boston Globe persuaded a Massachusetts court to release copies of disputed evidence the Republican candidate gave during litigation between a friend and business associate, Tom Stemberg, and Mr Stemberg's ex-wife, Maureen.

Mr Stemberg had founded the stationery chain Staples with the help of Mr Romney's private equity firm, Bain Capital, during the 1980s. When a divorce court attempted to establish his net worth, Mr Romney was called upon to testify as to the value of the retail company.

He is believed to have told the court that Staples shares, which at the time were trading for a little over $2, were "overvalued" and suggested that the company was in difficult financial straits. When the divorce was finalised in 1988, Maureen Stemberg was given 500,000 shares in the firm, and quickly sold half of them.

Months later, Staples went public in a move that pushed the value of its shares to $19. Ms Stemberg promptly sued her ex-husband, alleging that she had been encouraged to offload her stock for less than its true value. Litigation dragged on until 2002.

Lawyers for the Boston Globe recently requested a transcript of Mr Romney's original evidence. The Republican candidate's lawyers did not object and have insisted that "tabloid charges" suggesting their client lied under oath are "absolutely false". There was a carnival atmosphere to proceedings at Norfolk County Probate court, thanks largely to the presence of Gloria Allred, a celebrity lawyer from Los Angeles, who is representing Mrs Stemberg.

Ms Allred, a prodigious self-publicist, achieved fame as the attorney for the family of OJ Simpson's wife Nicole at his 1995 murder trial. She has litigated a number of high-profile cases that advance progressive causes, and represented the former mistresses of everyone from Tiger Woods and Eddie Murphy to former Republican presidential candidate, Herman Cain.

She is also a well-known supporter of Barack Obama, leading critics to complain that her interest in the Stemberg case is politically motivated.