Medical experts testifying before Congress Wednesday slammed the diagnosis that led to the controversial release of Lockerbie bomber Abdelbaset Ali Mohmet al- Megrahi, who is still alive more than a year after being told he had just weeks to live. 'I'm not the least bit surprised that Mr Megrahi is alive today, and it should come as absolutely no surprise to the cancer specialists who cared for Mr Megrahi either,' said James Mohler, an oncology specialist who testified before the US Senate Foreign Relations committee. The only man convicted in the bombing, Megrahi was freed by Scotland's devolved government on compassionate grounds, after being diagnosed with terminal prostate cancer and given just three months to live. More than a year later, the convicted Libyan terrorist is still alive however, sparking fury among Americans who believe he should never have been released in the first place. Mohler said it is clear that the diagnosis used to free him was deeply flawed. 'It would be very difficult to give a three-month prognosis to a patient who was able to negotiate a flight of stairs,' said Mohler, referring to widely broadcast video images that showed Megrahi descending aircraft stairs upon his return to Libya. Another physician at the hearing, Oliver Sartor, concurred with Mohler's assessment, and said he likely would have given a patient in similar condition who had received chemotherapy treatment -- as Megrahi had according to some documents -- a prognosis of around 19 months to live. Megrahi was convicted for his role in the 1988 downing of a Pan Am jumbo jet over Lockerbie, Scotland which killed 270 people, most of them US nationals. His released has galled lawmakers like US Senator Robert Menendez, who chaired Wednesday's hearing and called the Libyan's release a 'miscarriage of justice.' 'The release on compassionate ground was deeply deeply flawed,' said Menendez. The Senate Foreign Relations Committee also examined claims that oil giant BP played a part in securing Megrahi's release in a bid to safeguard a 900-million- dollar (700-million-euro) exploration deal with Libya. BP and the British government deny this however, and the Scottish government refused to send ministers to testify before the committee. 'Over 30 people were asked for cooperation -- all refused,' said Menendez. He said that among those asked to testify was BP's chief executive Tony Hayward -- already a deeply unpopular figure in the United States for his handling of the massive Gulf of Mexico oil spill. 'I frankly don't know how BP expect to continue to do business in America if this is the way they treat Americans,' the Democratic lawmaker said. Senators on the panel also heard testimony from a top official in the US State Department's European affairs bureau, and a senior US Justice Department official. 