Haris Kastanidis studied law at the Aristotle University of Thessaloniki. A member and cadre of PASOK since the early 1970s, he was elected to Parliament for the first time in 1981. He served in a series of ministerial posts since 1985, including as Minister of Justice, Transparency and Human Rights, from 2009 to 2011. He left PASOK to found Social Accord (Kinoniki Simfonia), a short-lived party, in 2012. In 2015 he joined Movement of Democrats and Socialists (KIDHSO), a small party founded by former PASOK leader and Prime Minister George Papandreou. He was reelected to Parliament with Movement for Change (Kinima Allagis), a merger of PASOK, KIDHSO and other small parties, in 2019.