Back in Soviet times, Yuris Taskovs snitched to the K.G.B. about a neighbor watching German pornography and betrayed hundreds of anti-Kremlin activists. So he and others like him knew that if the secret police files from Latvia were ever made public, which they finally were last month, their nefarious activities would be revealed.

Not that Mr. Taskovs is particularly concerned. “For 12 years, I worked for them with great enthusiasm,” the 63-year-old Latvian said of his time as an informant for the K.G.B. before the 1991 collapse of the Soviet Union.

For many others, however, the appearance of their names, code names and dates of recruitment in the recently released K.G.B. documents has come as a traumatic surprise.

“I am in shock. I had no idea,” said Rolands Tjarve, the former director of Latvia’s post-independence national broadcaster and now a professor at the University of Latvia. Insisting that he never served as an informant — or what the K.G.B. called in the files an “agent” — he said he would go to court to clear his name.