During the Cold war, the Communists often mentioned that former Nazis and Nazi collaborators were employed in Western Germany, France and other countries. On the one hand, it seems like propaganda. On the other, looking up various Nazi war criminals many got off easy or were amnestied in Germany and other countries after the war (the Peck panel) while in Poland, Yugoslavia and the USSR the Nazis were sentenced to death and executed. Also you would expect that the Eastern European countries would be more strict with the former Nazis because:
Absolutely no. It was one of the myths of the communist propaganda. After 1989, the Czechoslovak government released quite a few materials where the former Nazi criminals even the one who were responsible for the worst massacres on its territory were utilized by the communist apparatus. You can look into a life of the former Nazis in Protectorate like Max Rostock who was responsible for the massacre of Lidice to work for the Czechoslovak intelligence for a deal to spare his life from the death penalty in the 1950.
Each country in the Eastern Block dealt with the WWII collaborators differently depending on the pre-war situation, war situation, and postwar retribution. Within the Czechoslovak judicial system, the idea of postwar trials and retribution was already formed in 1943/44 and finalized before Prague was liberated by a series of decrees by the government in Exile. Generally, obvious collaborators were mercilessly hunted down at the closing days of the war and were brought in front of the retribution tribunal. Within the Czechoslovakia, about 740 people. Even women like brought in front of the tribunal, charged with a treason, and executed. However, a few valuable Gestapo, SS, and various Nazi individuals quickly trade their life or ideology or just the opportunity to serve the Communist regime. The acquirement of the Max Rostock into the service of the Czechoslovak communist intelligence was an insult for 100s of victims from Lidice and Marshall law. Others like Werner Tutter, Kurt Wilfer were imprisoned after the war, only to be selected to become agents of the communist regime. There were quite a few of them in the 50s. Their war crimes were pardoned by the president.
Various university studies exist from post 1989 years and were published as a monogram or article in peer review material. Other documents are available from the archive, but they are in Czech like Nazi Agents in the Service of the Communist Intelligence
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