From 1952 to 1975, Peet produced the Democratic German Report, a newsletter targeting the left-of-centre public opinion in the United Kingdom. His positive portrayal of the GDR was among the GDR's most believable and powerful propaganda in Britain. He spent the last ten years of his life translating Marx and Engels into English. Many East Germans saw Peet as the archetypical Englishman, and he played this character in several East German films. In his posthumously published memoirs, Peet writes about his defection stating he "could no longer serve the Anglo-American warmongers ...". He also writes about his links to Soviet intelligence. Peet was married three times and had two children.