Germany’s Federal Constitutional Court has ruled that parts of the 2023 electoral reform are unconstitutional. This reform aimed at reducing the size of the Bundestag, Germany’s federal parliament. The court specifically highlighted that the 5 percent electoral threshold, inherent in Article 4(2) second sentence no. 2 of the Federal Elections Act, violates Articles 21(1) and 38(1) of the Basic Law. The reform was set for implementation in the 2025 federal elections and primarily put smaller parties at a disadvantage.
The 5 percent threshold, known as the ‘Grundmandatsklausel,’ requires parties to secure at least 5 percent of the national vote to gain representation in the Bundestag. The threshold aims to prevent parliamentary fragmentation and ensure legislative functionality. On March 17, 2023, the ruling coalition parties—the Social Democrats, Greens, and Free Democrats—passed an electoral reform abolishing the exception that allowed a party to be represented if it won at least three constituencies despite not meeting the 5 percent threshold. This change put smaller opposition parties such as the Bavarian Christian Social Union and the Left Party at risk, prompting them to challenge the reform in court.
The Federal Constitutional Court’s decision ensures that the exception continues to apply, thereby protecting the representation of smaller parties. Other aspects of the reform, which targeted the reduction of the Bundestag’s size from 736 to 630 members, were approved. These included the abolition of the overhang and compensatory mandate system, a feature of Germany’s complex electoral law.
Germany’s electoral system allows each voter to cast two votes: one for a candidate in their constituency and another for a party at the state level, with parliamentary seats allocated based on the proportion of party votes. If a party wins more local constituencies than its proportional share of votes, it receives additional seats known as overhang mandates, with compensatory seats allotted to other parties to maintain proportional representation.
The full judgment can be read here, and more details are available on the JURIST website.