Labour MP Tom Watson has written to Strathclyde Police urging them to investigate News of the World Editor Bob Bird’s testimony at the Tommy Sheridan perjury trial, after a Freedom of Information request revealed that key emails relating to the trial had been stored in London, and not shipped to India as claimed at the trial.

The Information Commissioner has said there are "continuing concerns" about the evidence.

The emails in question were sent between the Scottish News of the World and private investigator Glenn Mulcaire, who was yesterday further implicated in hacking into the mobile phone of murdered teenager Milly Dowler.

The Information Commissioner said :"despite what was said in court, no e-mails of related personal data was ever transferred to India".

Watson said that the jury in the Sheridan case had not had an opportunity to assess all the evidence.

“I believe that a decision was made on the basis of inaccurate evidence at the trial,” he said.

“Because these e-mails were suppressed from the jury, its members were not in full possession of the facts of the case. Mr Sheridan could have been a free man now if the jury had been in full possession of the News International e-mails."

Sheridan family solicitor Aamer Anwar said that the email data disclosed by the Information Commissioner had been requested by him as Sheridan’s defence solicitor.

“During the trial, this information not disclosed to us had been requested from News International. It was a process that was like getting blood out of a stone,” he said.

“If it was a mistake that the e-mails were not lost, then it's a very serious mistake, and we'd like to know how it is going to be rectified. An MP has made an extremely serious allegation, and the police have a responsibility to investigate this.

"We've had great difficulty in getting our hands on this crucial material, which may form a part of the appeal.

"We've been left in darkness about the contents of these e-mails, but they could open up a can of worms."

Lothian and Border police have yet to respond to inquiries relating to the leak of Gail Sheridan's police interview material. The matter is currently under investigation by Holyrood MSP Mike Mackenzie.