A Warsaw court has cleared Poland's former president and Nobel peace laureate, Mr Lech Walesa, of spying for the communist regime his Solidarity movement helped to overthrow.
Prosecutors requested that the spying charge be dropped after it emerged that the communist secret police doctored files during the early 1980s in an attempt to discredit Mr Walesa and prevent him from winning the Nobel Peace Prize.
Mr Walesa, who was awarded the prize in 1983, smiled as the judge announced that he was cleared of any suspicion of collaborating with the intelligence services.
Under a law introduced two years ago all senior officials and candidates for the presidency must sign a declaration stating whether they worked with the secret police. Mr Walesa and Poland's current President, Mr Aleksander Kwasniewski, were the only candidates for this year's presidential election who were required to appear before the vetting court.
Mr Kwasniewski, a former communist who is expected to win October's election comfortably, was cleared by the same court earlier this week. Mr Walesa, who was Poland's president from 1990 to 1995, enjoys the support of less than 5 per cent of the electorate.
The court said that Interior Ministry documents showed that the communist intelligence services doctored files on Mr Walesa in an attempt to discredit him in the eyes of his colleagues and admirers throughout the world. They appeared to have been motivated by a desire to prevent Mr Walesa receiving the Nobel Peace Prize.
"There was a plan to send a letter to the members of the Nobel prize jury. They decided to attach to the letter information revealing his secret collaboration," Judge Pawel Rysinki told the court.
The collapse of the case against Mr Walesa is a blow to Poland's unpopular centre-right government, which is accused by opponents of introducing the vetting law in the hope of embarrassing political rivals.