From Postwar: A History of Europe Since 1945, by Tony Judt (Penguin, 2005), pp. 697-698:
The Communist regimes did not merely force their rule upon a reluctant citizenry; they encouraged people to collude in their own repression, by collaborating with the security agencies and reporting the activities and opinions of their colleagues, neighbours, acquaintances, friends and relations. The scale of this subterranean network of spies and informers varied from country to country but it was present everywhere.
The consequence was that while the whole society thus fell under suspicion—who might not have worked for the police or the regime at some moment, even if only inadvertently?—by the same token it became hard to distinguish venal and even mercenary collaboration from simple cowardice or even the desire to protect one’s family. The price of a refusal to report to the Stasi might be your children’s future. The grey veil of moral ambiguity thus fell across many of the private choices of helpless individuals. Looking back, who—save a handful of heroic and unwavering dissidents—could pass judgment? And it is striking that many of those same former dissidents—Adam Michnik prominent among them—were the most vigorously opposed to any retribution for their fellow citizens….
In Germany … revelations concerning the size and reach of the state security bureaucracy had astonished the nation. It turned out that in addition to its 85,000 full-time employees the Stasi had approximately 60,000 ‘unofficial collaborators’, 110,000 regular informers and upwards of half a million ‘part-time’ informers, many of whom had no means of knowing that they even fell into such a category.* (*By way of comparison, the Gestapo in 1941 had a staff of fewer than 15,000 to police the whole of greater Germany.) Husbands spied on wives, professors reported on students, priests informed on their parishioners. There were files on 6 million residents of former East Germany, one in three of the population. The whole society had in effect been infiltrated, atomized and polluted by its self-appointed guardians.
To lance the boil of mutual fear and suspicion, the Federal Government in December 1991 appointed a Commission under the former Lutheran minister Joachim Gauck to oversee the Stasi files and prevent their abuse. Individuals would be able to ascertain whether they had a ‘file’ and then, if they wished, come and read it. People would thus learn—sometimes with devastating domestic consequences—who had been informing on them; but the material would not be open to the public at large. This was an awkward compromise but, as it turned out, quite successful: by 1996, 1,145,000 people had applied to see their files. There was no way to undo the human damage, but because the Gauck Commission was trusted not to abuse its powers the information it controlled was hardly ever exploited for political advantage.
Two out of four of my East German classmates in Romanian language class in Bucharest in 1983-84 were politically reliable and spying on the other two, as I discovered when I chanced upon one of the unreliables at a reception in the West German embassy. She panicked and implored me not to tell anyone. I didn’t, and when I went to the female foreign student dorm to pass my shortwave radio/cassette player on to one of my Chinese classmates before leaving Romania, Miss Unreliable insisted on giving me a grateful good-bye kiss. Saucy wench. I hope she and her fellow Unreliable survived reunification.
All my German classmates were primarily Russian translator/interpreters who added Romanian as backup. So perhaps one or both of the Reliables are now translating for former German Chancellor Gerhard Schroeder while he works for the Russians.