She undertook humanitarian efforts on behalf of members of the opposition who had been arrested and often tortured by the regime and of their family members left in poverty after the arrests. She was arrested in 1971 and sentenced to sixteen months in prison for plotting the escape from jail of Alexandros Panagoulis who had been convicted of attempting to assassinate Georgios Papadopoulos, the head of the military junta. She was released from prison less than a month later due to health problems but was stripped of her Greek citizenship and deported to Britain. Over the following few years in London, she mounted, in conjunction with Melina Mercouri and Helen Vlachos, a "non-stop publicity campaign" against the Greek dictatorship until it finally collapsed in 1974. Fleming also made representations to the Human Rights Commission in Strasbourg regarding the torture of Greek political prisoners, continued to help imprisoned regime opponents and their families, and helped a number of the junta's opponents to escape from Greece. Fleming returned to Greece in 1974 after the fall of the junta. She joined the Panhellenic Socialist Movement (or PASOK) and was elected to the Greek Parliament in 1977, 1981 and 1985. She was an active campaigner for human rights and was a member of the European Commission of Human Rights and the first chair of the Greek committee of Amnesty International. Fleming lived in a single room flat with a number of cats on whom she doted. She died in 1986. Fleming saw herself as a Greek patriot and a defender of democracy and independence, stating: "I was born a Greek and this is an incurable disease that nothing and no one can treat or change". After her death, the Greek government lamented her loss and praised her as "a great humanitarian, a fine democrat and a fighter for the Socialist cause". She established the Greek Foundation for Basic Biological Research "Alexander Fleming" and "created the conditions to set up" the Biomedical Sciences Research Centre "Alexander Fleming" (often referred to as BSRC "Alexander Fleming" and the Alexander Fleming Biomedical Sciences Research Center), in Vari, a suburb of Athens. In 1986 a hospital was founded at Melissia, a suburb of Athens, and named after her (currently known as Sismanogleio-Amalia Fleming General Hospital).