In the 1980s he was active in Hesse for the party, was a municipal councillor in Frankfurt 1981–1983, and was elected to the Bundestag in 1983, serving until 1985, as a member of its Foreign Affairs Committee.

His main interests there were foreign affairs and security, Central and Eastern Europe and human rights.

As a candidate of the Green Party federations of Saxony, Saxony-Anhalt and Thuringia he was elected to the European Parliament in June 2004.

He also participates in activities of Green Party in the Czech Republic and was not reelected to European Parliament in June 2009.

[1] In 2008, he co-organized (with Gisela Kallenbach) a public hearing in the European Parliament on totalitarian regimes in support of the Prague Declaration.