After the war, she joined the Socialist Unity Party of Germany (SED) in 1946 and was vice president of the Supreme Court of the German Democratic Republic (GDR) from 1949 to 1953. In that capacity, she assisted with the Waldheim Trials and presided over a series of show trials against those identified as political undesirables, such as Johann Burianek and Wolfgang Kaiser, as well as against Jehovah's Witnesses. Her two death sentences earned her the popular sobriquets "The Red Guillotine" and "Bloody Hilde" in Western media.