In the artist's words:

Gerhart Rudolf Baum (born October 28 , 1932 in Dresden) is a German politician(FDP) and lawyer.

Baum was Parliamentary State Secretary to the then Federal Ministers of the Interior Hans-Dietrich Genscher and Werner Maihofer from 1972 to 1978 and Federal Minister of the Interior in the Schmidt II and Schmidt III cabinets from June 1978 to September 1982. Even after his retirement from active politics, Baum is still considered one of the most prominent representatives of the left-liberal Freiburg Circle of the FDP alongside Sabine Leutheusser-Schnarrenberger. (Wikipedia)