Since September 1988 he was one of the leaders of the Karabakh Movement. In 1993 he left the Armenian National Movement (ANM) party.
From 1992 to 1995 he was the Ambassador at Large in charge of the negotiations on the Karabakh conflict resolution. In 1994 January he headed the State Department for National Security of RA and in 1995 resigned from the post.

In 1991 and 1995 he was elected as a Deputy of the National Assembly.

David Shahnazaryan is not associated with any political party. He is married and has two children and one grandchild.