It was the first time since the 61st Assembly, as well as the most recent legislature as of 2025, in which either party held a two-thirds supermajority in the State Senate.
Jane Cease resigned July 31, 1991 to accept appointment as Administrator of Motor Vehicle Division; Ron Cease was appointed by Multnomah County Commissioners to fill the vacancy on August 22, 1991.
Judy Bauman resigned on November 1, 1991, to accept appointment as Administrator of the Community Services Division.
Tom Brian changed parties, from a Democrat to Republican on September 5, 1991.
Bob Pickard changed parties from Republican to Democrat on September 12, 1991.