High Court judges urged to act over jailed Liverpool fan Michael Shields

Lawyers for jailed Liverpool fan Michael Shields argued today that he should be granted a free pardon because his conviction by a Bulgarian court of attempted murder was based on thin evidence.

Two High Court judges in London were urged to rule that Justice Secretary Jack Straw has the power to exercise the ancient "royal prerogative of mercy", even though Shields was convicted abroad.

The power to pardon is rarely used, but is exercised when a person is deemed to be "morally and technically innocent".

Shields, 22, is serving a ten-year sentence for the attempted murder of a barman at the Big Ben diner in Varna, Bulgaria, in 2005.

The barman was attacked a few nights after Liverpool FC's European Cup Final victory in Istanbul, Turkey.

Shields has always vehemently maintained his innocence, and Fair Trials Abroad described his conviction - based solely on identification evidence with no supporting testimony - as a blatant miscarriage of justice.

Another fan - not an associate of Shields - signed a statement admitting he was the man responsible, but the Bulgarian Supreme Judicial Council said the new evidence did not prove anything and merely introduced doubt.

At today's hearing, Shields's legal team sought a judicial review of Mr Straw's decision that he lacked jurisdiction to issue a pardon.

Lord Justice May and Mr Justice Maddison were asked to decide whether there were powers "to grant a pardon to repatriated prisoners wrongly convicted in a foreign jurisdiction".

The judges heard that Shields had taken a polygraph lie-detector test.

Defence lawyers said that, although this had little impact in law, it should be taken into account by Mr Straw.

The Bulgarian authorities had made no attempt to interview the man who confessed, known only as G, or to ask the UK authorities to do so.

The judges were told Mr Straw had taken a close interest in the case and had met the Bulgarian Minister of Justice, Miglena Techeva, to discuss the matter.

Recently Shields's mother, Marie, met the Prime Minister's wife Sarah Brown at 10 Downing Street over her son's case.

Shields was initially jailed for 15 years in Bulgaria, but was transferred to the UK in 2006.

He is currently serving the remainder of his sentence, which was cut to 10 years on appeal in Bulgaria, at HMP Haverigg in Cumbria.

The Bishop of Liverpool, the Right Reverend James Jones, has described the case as "a travesty of justice".

He said: "I have talked and listened to Michael on a number of occasions and I too believe that he is innocent."