Germany's top court: No constitutional speed limit for legislation, Heizungsgesetz challenge fails

## Background In summer 2023, the then-governing coalition of SPD, Greens and FDP pushed to pass the Building Energy Act (Gebäudeenergiegesetz), commonly known as the Heizungsgesetz, before the parliamentary summer break. The law aimed to make heating climate-friendly by requiring new systems to run on 65% renewable energy. However, the legislative process was marked by last-minute amendments and internal coalition disputes. Just days before the planned final vote on 7 July 2023, the government factions submitted extensive changes, prompting former CDU MP Thomas Heilmann to file an emergency motion at the Federal Constitutional Court in Karlsruhe.

The emergency ruling

The court granted Heilmann's emergency motion with a 5-2 vote, halting the second and third readings. The judges argued that MPs must not only receive information but also have time to process it. The law was subsequently passed on 8 September 2023, after a two-month delay, and took effect in January 2024. No further amendments were made during the extra consultation period. The law was later replaced by the current black-red coalition's Gebäudemodernisierungsgesetz, which softened its requirements.

The main decision

On 23 July 2026, the Second Senate of the Constitutional Court dismissed Heilmann's main complaint as inadmissible. The ruling was unanimous. Presiding Judge Ann-Katrin Kaufhold stated that the constitution sets a limit on accelerating legislative procedures, but not in the form of a numbered speed limit.

The constitution sets a limit on the acceleration of legislative procedures, but not in the sense of a numbered speed limit.

The court found that Heilmann had not sufficiently demonstrated that his parliamentary rights under Article 38 of the Basic Law were violated. The key test, according to the judges, is whether the process made public debate and the exchange of arguments impossible. The original draft and a formulation aid provided a sufficient basis for discussion, the court said.

Reaction and implications

Heilmann had argued that the hasty process violated the rights of all MPs to adequate consultation time. He described the Heizungsgesetz as an "extreme case" of a practice where MPs receive hundreds of pages of amendments the evening before a final debate.

It's not about me alone, but about the right of all MPs to sufficient consultation time.

The ruling strengthens the hand of government factions to fast-track legislation, but also sets a high bar for constitutional complaints against rushed lawmaking. The court noted that the issue remains topical, citing two emergency motions in the last week of the Bundestag before the 2026 summer break concerning the GKV-Modernisierungsgesetz, which was also pushed through quickly.

Broader context

The decision ends a three-year legal saga that began with the halt of the Heizungsgesetz in 2023. While the emergency ruling was seen as a check on executive overreach, the final judgment clarifies that the constitution does not impose a specific time limit on legislative deliberation. The court's reasoning emphasizes that the democratic process is not undermined unless parliamentary debate is rendered impossible, a threshold Heilmann failed to meet.