Federal Constitutional Court: Green light for new electoral law – with one restriction

The proposal has been in place for a few days: According to the will of the federal government, the new Bundestag should be elected on September 28, 2025. It was previously questionable whether the reform of the Bundestag electoral law introduced by the traffic light coalition could serve as the basis for this. The Federal Constitutional Court had to examine several lawsuits on this matter. Reading out this long list at the announcement alone took almost six minutes, and welcoming the representatives present took about the same amount of time.

The most important question first: Can we hold elections next year?

Yes. The highest German court has declared the reform to be largely constitutional. Only the five percent hurdle without a so-called basic mandate clause violates the Basic Law. According to this rule, the limit for the Germany-wide share of second votes is eliminated for those parties that have won at least three direct mandates. In the 2021 election, the Left Party benefited from this, only entering parliament as a parliamentary group because three of its people received the most first votes in their constituencies.

Is further reform necessary?

Not immediately. The court has decided that the basic mandate clause that was deleted by the traffic light reform will remain in force until the Bundestag creates a new regulation. So if nothing changes by autumn 2025, the election will be held under these conditions.

Consequently, representatives of the governing coalition such as Till Steffen (Greens) and Sebastian Hartmann (SPD) appeared relaxed after the verdict was announced. First, the verdict must be examined carefully, then possible steps will be discussed – including with the Union. That did not sound like a hasty decision before the 2025 federal election. SPD parliamentary group leader Rolf Mützenich, for example, again considered it possible to change the electoral law in accordance with the new requirements before the next election in the “Rheinische Post” (Wednesday).

Was reform even necessary?

Basically everyone agrees: Yes. Because the Bundestag is growing and growing according to the current regulations – and is therefore becoming more and more expensive. In the 2021 election, the number of MPs rose from 709 to 736 – making the German Bundestag the largest freely elected parliament in the world. The previous reform of the grand coalition of CDU/CSU and SPD only managed to slow the increase in the number of MPs.

What did the new reform look like?

The new electoral law passed by the SPD, Greens and FDP in 2023 caps the number of seats at 630 parliamentarians. To achieve this, overhang and compensatory mandates were primarily eliminated. Until then, overhang mandates arose when a party won more direct mandates via the first votes than it was entitled to seats based on the second vote result. It was allowed to keep these mandates. The other parties received compensatory mandates in return so that their strength again matched the proportion of second votes. And the basic mandate clause was also eliminated with the reform.

What consequences could the reform have had?

In addition to the Left, the changes meant a lot was at stake for the Union in particular. In the 2021 federal election, the CSU, which is only running in Bavaria, won 45 direct mandates. Eleven of these were overhang mandates that it would no longer receive under the new electoral law. The CDU won a further twelve overhang mandates in Baden-Württemberg. In total, this was 23 of 34 overhang mandates, which in turn resulted in 104 compensatory mandates.

If the CSU were to fall below the five percent mark nationwide in the next election, it would be thrown out of the Bundestag under the new electoral law – even if it were to win the vast majority of constituencies in Bavaria directly again. In the 2021 election, the CSU received 5.2 percent of the second votes nationwide.

What did the court decide?

The limitation of the Bundestag to 630 members and the elimination of overhang and compensatory mandates remain in place. The Senate unanimously decided that the so-called second vote coverage procedure is compatible with the constitution. Accordingly, the 630 seats are initially distributed among the parties and their state lists. When filling the seats, constituency candidates move to the top of the state list in the order of their vote share. Only in the last step do all candidates receive their mandates in this order.

Only the five percent threshold in its current version is unconstitutional in the view of seven of the judges – with one dissenting vote. Therefore, the Senate essentially reinstated the old rule, which allows a party to enter parliament as a parliamentary group if it wins at least three direct mandates.

The court also sees no problem in the fact that some constituencies may not be represented by a politician in the Bundestag. Nor does the electoral law have to be designed in such a way that constituency candidates from each federal state enter the Bundestag in proportion to the population. “It would be wrong to regard constituency representatives as delegates of their constituency anyway,” said presiding judge Doris König. According to the Basic Law, they are representatives of the entire people and are responsible only to their conscience. (Az. 2 BvF 1/23 et al.)

What are the possible solutions to the blocking clause?

Particularly in view of the long-standing and ongoing cooperation between the CSU and CDU, including a joint election program and a joint parliamentary group, the Senate proposes that cooperating parties should also be considered together when applying the threshold clause. However, the next sentence states that other variants of the change are also conceivable. In principle, the legislature has a lot of leeway and, in the Senate’s opinion, may also introduce innovations in electoral law that “require voters, candidates and parties to rethink their approach.”

Who are the winners and losers of the decision?

Depends on who you ask. The SPD, Greens and FDP welcome the fact that the heart of their reform – the capping of 630 seats – has been given the green light by the Constitutional Court. Representatives of the Left and the Union, on the other hand, are particularly pleased about the revival of the basic mandate clause – and that the traffic light coalition has thus suffered at least a partial defeat.