Germany's Federal Constitutional Court on Tuesday essentially approved the electoral law reform which ensures that the Bundestag, Germany's lower house of parliament, will be limited in size.

"The Federal Constitutional Court has saved this law, has made it watertight to a certain extent," political scientist Albrecht von Lucke told DW after the verdict was published.

However, the court has also ruled that parts of the government's recent reform are "incompatible with the Basic Law," dealing a victory to two small parties — the Socialist Left Party and the center-right Bavarian regional Christian Social Union (CSU).

In March 2023, the three ruling parties — the center-left Social Democrats (SPD), the Greens and the neoliberal Free Democrats (FDP) — together passed a new electoral law aiming to limit the size of Germany's lower house of parliament, the Bundestag, to 630 seats. With the last general election in 2021, it had ballooned to 736 members, making it larger than any other democratically elected parliament in the world — and very expensive.

The Federal Constitutional Court overturned one of the points of this electoral law reform. "The 5% clause in its current form is not compatible with the Basic Law," it wrote, referring to the threshold a party needs to cross to secure representation in the Bundestag.

This clause has long been part of Germany's electoral law. Still, the ruling parties had modified part of it, abolishing the  "Grundmandatsklausel" (basic mandate clause), which enabled a party that won at least three constituencies ("direct mandates") to enter the Bundestag with a full parliamentary group even if failed to clear the 5% threshold to enter parliament.

The Left Party benefited from this clause in the 2021 election. It had won only 4.9% of the vote, but because three of its candidates won their respective constituencies, the party got to fill 4.9% of the Bundestag seats, giving it a parliamentary group of 39 members.

Left Party co-chair Janine Wissler was jubilant in her first reaction to the verdict. She wrote on X, formerly Twitter, of a slap in the face of the government, "who wanted to weaken the opposition via the electoral law."

Most of the new electoral law faces no objection

Germany's electoral system is famously complicated. Voters cast two votes: one for a deputy to represent their constituency and one for their preferred party. The latter determines the number of lawmakers representing the parties.

The seats in the Bundestag are filled with directly elected lawmakers from the constituencies and others who come in from lists according to the proportion of the vote the parties receive nationally.

Until now, each directly elected representative was entitled to a seat in parliament. When a party won more constituencies than the number of seats they were entitled to according to the proportion of their national vote, the directly elected representatives would still get a seat in parliament, leading to so-called "overhang seats" (Überhangmandate).

"Balance seats" (Ausgleichsmandate) were then granted to the other parties to ensure they all get the proportion of seats determined by the party vote. In the most recent Bundestag election in 2021, this resulted in a total of 138 extra seats.

The center-right Christian Social Union (CSU), which competes only in the state of Bavaria, has benefited from the current electoral system and is worried it could lose representation. While it wins only around 5% of the national vote, its candidates tend to come in first in the majority of Bavarian constituencies, guaranteeing a large CSU bloc in the Bundestag.

The latest reform seeks to abolish this procedure: If a party wins more constituencies than it deserves according to the national vote, those directly elected candidates will no longer be sure to get a seat in parliament.

The Constitutional Court did not find fault with this part of the reform.

The way ahead

There is not much time left until the upcoming Bundestag election in just over one year's time,  in September 2025. The court has therefore ordered a transitional rule to maintain the 5% threshold combined with the basic mandate.

The Left Party's Gregor Gysi is one of the lawmakers who won his constituency in 2021. In an interview with DW, the lawyer called Tuesday's verdict a "success for the left and the CDU/CSU" and a "failure" for the governing parties.

He said he was hoping for a reformed electoral law to swiftly be put to the Bundestag for a vote and passed by September. He would like to see the 5% threshold abolished, but said he does not believe this will happen.

Edited by: Timothy Jones

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