1996 – 1999 legal speaker of the German branch of Friends of the Earth (Bund fuer Umwelt und Naturschutz Deutschland).
1999 to 2001 member of the town council of Goettingen.
Elected member in advisory boards, for example 2003 – 2009 the board for environment and sport of the Federal Ministry of Environment.
Since 2005 representative member of the State Court of Lower Saxony.