How did the constitutional reforms of 1989 change Poland’s legislature?

The constitutional reforms of 1989, negotiated between the Polish government and Solidarity, significantly restructured Poland’s legislature by establishing a bicameral system.1

Key changes included:

• Reinstatement of the Senate: The Senate, which had been abolished in 1946, was restored as the upper house of the legislature with 100 members.1
• Redefinition of the Sejm: The existing Sejm, consisting of 460 members, was designated as the lower house.1
• Legislative Authority: These reforms set the stage for a transition toward a more democratic parliamentary framework, later complemented by additional measures such as the guarantee of free political party formation.1

These changes were part of a broader political transformation that moved Poland away from its postwar socialist structure toward a democratic system, eventually leading to the adoption of a new constitution in 1997 that solidified the roles and powers of both houses of parliament.1