The Bundesrat represents governments, not a second elected chamber
The Bundesrat is composed of members of Germany's Land governments. Each Land has a constitutionally determined number of votes and must cast its votes as a unit.
That structure gives regional executives a direct institutional role in federal politics.
Its power depends on the type of legislation
Some federal laws require Bundesrat consent, particularly where the Basic Law gives the Länder a protected role. For other legislation, the Bundesrat may object under procedures that can allow the Bundestag to overcome the objection.
The Mediation Committee provides a mechanism for negotiating disagreements between the Bundestag and Bundesrat.
Constitutional change gives the chamber exceptional leverage
Amendments to Germany's Basic Law require a two-thirds majority in both the Bundestag and Bundesrat, subject to constitutional limits on what may be amended.
Federal reform therefore cannot be understood through Bundestag arithmetic alone.