In 1989, after election laws changed during Perestroika, he was elected as an independent candidate to the Congress of People's Deputies of the Soviet Union. He was one of only a few deputies who had a legal background, so he contributed enormously to most of the laws created from 1989 to 1991. He became one of the founders and a co-chairman of the Inter-Regional Deputies Group along with Andrei Sakharov and Boris Yeltsin. He also was a chairman of the Parliamentary Commission on the Investigation of the events of 9 April 1989 in Tbilisi. The Commission condemned the military, which was blamed for many deaths when dispersing demonstrators. The Commission's report made it more difficult to use military force against civil demonstrations in the Soviet Union and Russia.