By Gabriel Partos BBC Central and South-East Europe analyst

Stanislaw Wielgus resigned despite Vatican backing

Monsignor Wielgus resigned following revelations about his involvement with Poland's secret police during the communist era.

Since the restoration of democratic government, a whole host of prominent politicians, officials, artists and writers have been accused of having collaborated with the old secret police.

Some have been forced to step down from their posts.

Nearly two decades after the fall of the Berlin Wall, the spectre of the communist secret police continues to haunt the countries of central and eastern Europe.

Accusations are being levelled against individuals in all walks of life.

Surviving accusations

And increasingly these claims have been backed by evidence, not always entirely reliable, from special institutes set up to provide a record of the activities of the communist-era secret police.

No one is immune to the accusations.

Only a couple of months ago Romania's President, Traian Basescu, was cleared for the second time of persistent charges of collaboration.

DECLASSIFYING SECRET FILES Details of countries' policies

Mr Basescu, a ship's captain during the communist period, said he had compiled routine reports for his superiors after his foreign trips, but he denied that he had ever worked for the secret police.

By contrast, Mr Basescu's Bulgarian counterpart, Georgi Parvanov, acknowledged last year that he had been involved with the former secret service.

But his portrayal of his earlier role as a young historian who had contributed in an entirely harmless way to a publication about an eminent Bulgarian emigre, found wide acceptance among the Bulgarian public.

Just a few months after his admission Mr Parvanov, the former "Agent Gotse", was re-elected president in a landslide victory.

Another self-confessed agent was Hungary's former Prime Minister, Peter Medgyessy, who was revealed to have been agent "D-209" just weeks after he became head of government in 2002.

But Mr Medgyessy, a long-standing financial expert, managed to neutralise the issue.

He explained his task with the security authorities in the early 1980s had been to keep sensitive information, such as Hungary's plans to join the World Bank and the IMF, from foreign intelligence agencies, not least from the KGB which might have wanted to torpedo such moves.

Security presence

These prominent cases highlight three key issues relating to past collaboration with the secret police.

Hungary's ex-prime minister kept his post despite having collaborated

One was the sheer extent of the security presence in all areas of society - whether to do with academic institutes or those involved in foreign travel.

Another was the way in which individuals may have done work, for example, compiled reports which were then passed on, without their knowledge, to the secret police.

And last, but not least, there was a crucial distinction between working for one's country, for instance, by gathering intelligence abroad, and spying on one's colleagues, friends and even family at home.

That distinction was blurred however by the structure of the secret police which, following the pattern of the KGB, combined these different functions within one huge organisation.

Besides, working abroad for the secret police in those days would not necessarily be acceptable by today's standards: quite often it might involve spying on fellow-citizens or emigre groups.

Politicians may have borne the brunt of accusations of collaboration, not least because it has been a good way for their opponents to try to destroy their reputations.

Cultured collaborators

But other professions have also had their fair share of informers.

Just over a year ago the head of the Romanian Writers' Union, Eugen Uricaru, stepped down after accusations that he had been informing on communist-era dissident intellectuals for the Securitate - a charge he denied.

Hungarian film director Istvan Szabo defended his collaboration

And last year the Oscar-winning Hungarian film director, Istvan Szabo, admitted that as a student at Hungary's theatre and film academy he had worked for the secret police, but only to save the life of a fellow-student who was facing a death sentence after the Hungarian uprising of 1956.

There were all kinds of reasons for individuals to collaborate - whether to secure a university education for their children, foreign travel for their families or to avoid being sacked from their jobs.

Dealing with that legacy has been a tricky task for another reason, too: quite often the former secret police files do not distinguish between willing agents, reluctant informers and their targets.

By and large, though, the thirst for information, and sometimes for political advantage, has led most formerly communist-ruled countries to adopt some variant of the system pioneered in Germany - setting up an archive where information about the old security apparatus is made accessible.

In central Europe interest in the activities of the communist-era secret police remains frequently as lively today as it was in the early 1990s.

By contrast, in the former Soviet Union, apart from the Baltic states, there has been a very different approach.

On the whole the tendency has been to throw a veil over this aspect of the communist past.