London's High Court has decided that Justice Secretary Jack Straw has the power to exercise a possible pardon in the Michael Shields case. The ruling could prove an important landmark in Shields' battle to win his freedom although, in itself, it is not necessarily mean he will be freed.

Shields (22) is currently serving a 10-year sentence for the attempted murder of Bulgarian barman Martin Georgiev in Golden Sands in 2005. He has always maintained his innocence.

The two senior judges also ruled that it was for Straw alone - and not the courts - to decide how to exercise that power.

The judges said the pardon relied upon fresh evidence which had not been considered by the Bulgarian courts. A confession by another Liverpool fan, Graham Sankey, which he later retracted, would not form part of the new evidence, the judges said.

In court the judges said: "It is, in our judgment, open to the Secretary of State to entertain a request to exercise the royal prerogative. It is not for this court to say whether or how it might be exercised."

Straw said he would appoint senior counsel to advise him on whether to pardon Shields or not, in light of the High Court decision. The Justice Secretary said the case had to be examined very closely, along with the implication it could have on cases of other British prisoners abroad.

He added: "I will ensure this process is undertaken as quickly as possible, and can assure Michael Shields and his family that I will reach a decision on whether to recommend granting a pardon as swiftly as is possible."

Media and celebrities in Liverpool have also thrown their weight behind the campaign to free Shields. Local newspaper Liverpool Echo (no relation to The Sofia Echo) has been particularly vocal in the campaign but so, too, have celebrities such as actress Sue Johnston, star of the TV series The Royle Family, and Liverpool football club.