Lech Walesa, the Polish shipyard worker with the trademark droopy moustache, is regarded as one of the heroes of modern Europe: the leader of the revolution that brought communist rule crashing down.

Now Poland is in uproar over an intriguing riddle: was communism actually destroyed by a communist agent? If so, why?

Two writers claim that Mr Walesa — the founder of the Solidarity movement, Nobel Peace prizewinner, former President of Poland - was a stooge of the communist secret police.

In The State Security Service and Lech Walesa, Slawomir Cenckiewicz and Piotr Gontarczyk make two central claims. The first is that Mr Walesa was an informer for the secret police between 1970 and 1976 under the codename “Bolek”. The second is that as President from 1990 to 1995 he borrowed his police file from the Interior Ministry archives and returned it with key pages missing.

Mr Walesa has already successfully contested in the courts that he was Bolek. His argument, backed by a handwriting expert, is that documents were faked by the secret police to discredit him with the Church hierarchy, to sabotage his relationship with the Polish-born Pope John Paul II and to influence the Nobel Peace Prize committee against making him a laureate.

Most of the documents found by the authors in the Institute for National Remembrance (IPN) are photocopies and many are unclear. It is certainly true that the secret police, the notorious SB, concocted material to compromise Mr Walesa. The short, fast-talking electrician was a profound embarrassment for the regime in the 1980s, largely because he embodied the romantic idea in the West that the Soviet empire could be brought to its knees by a simple worker.

In his autobiography Mr Walesa admits that he may have “signed something” after an interrogation in the early 1970s. There was never any possibility, he says, that he would co-operate with the SB, betraying fellow dissidents. The book tells a different story.

“We provide clear evidence in our book,” Mr Cenckiewicz says, “registration cards, memos, notes from the secret police . . . we know the secret police methods and the way that the archives and registry were run.”

Documents implicating Mr Walesa, he says, were found in other archives. “These files still had their original seals and it could be proven that they haven't been opened since the 1970s. Manipulation is out of the question.”

If Mr Walesa was Bolek, what damage did he cause? The authors say that he informed on about 20 people who were later harassed or oppressed. Oppositionist activity, however, was minimal and Mr Walesa's role in it marginal. He came to the notice of the police during riots against food price rises in December 1970. As workers prepared to storm the police headquarters in Gdansk, Mr Walesa pushed his way inside and offered the commander a deal: the workers would not attack if jailed colleagues were freed. He was given a megaphone to address the crowd. Unbeknown to him, the police were ready to shoot. The tragedy unfolded - but the police may well have spotted a useful ally.

If there was a relationship with the secret police, did it really end in 1976 (when Mr Walesa was dismissed from his workplace)? The opposition to communist rule was beginning to take real shape in 1976. Intellectuals such as Jacek Kuron formed a committee to defend sacked and persecuted workers. Informers from within the factories had never been so valuable.

The conspiracy theories go farther. If Mr Walesa continued as an agent, what really happened in the shipyard strikes of 1980? Were the police trying to engineer a change in the communist party leadership? Were there elements of the police that wanted to get rid of communism altogether?

The shadows over Mr Walesa stretch into his presidency. One of his key advisers was his chauffeur, a former SB operative. And the new book is quite solid about President Walesa's various requests for his secret files; the pages that he removed were clearly documented by the archivist. Mr Walesa's defenders say that the book is a political put-up job. The head of IPN was appointed by President Kaczynski, no friend of Mr Walesa.

“We consider Walesa to be a national symbol. He led Solidarity and remains an icon,” Mr Cenckiewicz says, “but he also worked with the secret police under the name Bolek. The truth isn't always black and white.”

— Roger Boyes is the author of The Naked President, a biography of Lech Walesa. His reporting from that period can be accessed on the Times Archive.

Rallying cry

1986, addressing a meeting of the US Congress

“We have had many beautiful words of encouragement but, being a worker and a man of concrete work, I must tell you that the supply of words on the world market is plentiful, but the demand is falling. Let deeds follow words now”

2005, at the 25th anniversary of the Polish Solidarity movement

“Freedom came, but it is still hard to get bread”

1983, in his Nobel lecture

“Let the veil of silence fall presently over what happened afterwards. Silence, too, can speak out”

1983, in his Nobel lecture

“The defence of our rights and our dignity as well as efforts never to let ourselves to be overcome by the feeling of hatred — this is the road we have chosen”

2008, after receiving treatment in hospitals for a weak heart

“It has been a long time since I have felt this good . . . I hope to work harder than ever to help people around the world. Dictators and oppressors should continue to fear me because I will be here for a long time”

Sources: Times archives; brainyquote.com

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