Rennicke is one of the founding members of the Verein zur Rehabilitierung der wegen Bestreitens des Holocaust Verfolgten (Society for the Rehabilitation of Those persecuted for Refutation of the Holocaust), an organisation originally proposed and founded by the former Red Army Faction lawyer Horst Mahler.
Rennicke is one of the founding members of a society dedicated to rehabilitating individuals who were persecuted for opposing the Holocaust, which was originally conceived and established by the former Red Army Faction lawyer Horst Mahler.