MICHAEL SHIELDS and his legal team have a month to convince Jack Straw that he should grant a Royal Pardon.

If they deliver compelling new evidence by the August 3 deadline, the justice secretary promised to make a final decision "as quickly as possible.”

Mr Straw apologised to the 22-year-old and his family for the long delay before reaching yesterday's "provisional" ruling that he remained unconvinced that Michael was "morally and technically innocent.”

“I fully understand their anger and I understand that the delay has added to their distress,” he said. "But I spent a huge amount of time and care on this case.” Mr Straw insisted that his verdict was based purely on the remit given to him by December's High Court judgment, and he had been motivated by his duty to "uphold the law”.

And he denied he was hiding behind "legalese”.

He refused to be drawn on what evidence pointing to Michael's innocence he had rejected, saying such issues were included in a letter sent to Michael and his lawyers.

"Of course I understand the concerns of the family. But the High Court ruling, applied for by the family and which I did not appeal against, set a very high test that I should only consider the Bulgarian court's judgment.

"I could not call into question its correctness on the material it considered.

“It would be improper of me to reveal the contents of the very detailed letter I have sent to Mr Shields and his lawyers. What I cannot do is get into a debate about what kind of evidence I am seeking from the Shields family.

“People in Liverpool will be deeply disappointed. I understand the strong emotions felt by Mr Shields, his family and his many, many supporters in Liverpool and well beyond. I want to again stress, this is a provisional decision.“