The Federal Constitutional Court ( ; abbreviated: ) is the supreme constitutional court for the Federal Republic of Germany, established by the constitution or Basic Law () of Germany. Since its inception with the beginning of the post-World War II republic, the court has been located in the city of Karlsruhe, which is also the seat of the Federal Court of Justice.Donald P. Kommers & Russell A. Miller, The Constitutional Jurisprudence of the Federal Republic of Germany (3d ed.: Duke University Press, 2012), p. 40.

The main task of the Federal Constitutional Court is judicial review, and it may declare legislation unconstitutional, thus rendering it ineffective. In this respect, it is similar to other supreme courts with judicial review powers, yet the court possesses a number of additional powers and is regarded as among the most interventionist and powerful national courts in the world. Unlike other supreme courts, the constitutional court is not an integral stage of the judicial or appeals process (aside from cases concerning constitutional or public international law) and does not serve as a regular appellate court from lower courts or the Federal Supreme Courts on any violation of federal laws.

The court's jurisdiction is focused on constitutional issues and the compliance of all governmental institutions with the constitution. Constitutional amendments or changes passed by the parliament are subject to its judicial review, since they must be compatible with the most basic principles of the defined by the eternity clause.Art. 79 s. III

Scope The Basic Law of the Federal Republic of Germany stipulates that all three branches of the state (the legislature, executive, and judiciary) are bound directly by the constitution in Article 20, Section 3 of the document. As a result, the court can rule acts of any branches unconstitutional, whether as formal violations (exceeding powers or violating procedures) or as material conflicts (when the civil rights prescribed in the Basic Law are not respected).

The powers of the Federal Constitutional Court are defined in article 94 of the Basic Law. More detailed regulation is in the Federal Constitutional Court Act (Bundesverfassungsgerichtsgesetz), which also defines how decisions of the court on material conflicts are put into force. The Constitutional Court has therefore several strictly defined procedures in which cases may be brought before it: Constitutional complaint: By means of the Verfassungsbeschwerde (constitutional complaint) any person may allege that his or her fundamental rights have been violated, but only if all other legal remedies have been exhausted. Although only a small fraction of these are actually successful (ranging around 2.5% since 1951), several have resulted in major legislation being invalidated, especially in the field of taxation. The large majority of the court's procedures fall into this category; 135,968 such complaints were filed from 1957 to 2002. Municipalities and associations of municipalities may also file a Verfassungsbeschwerde alleging interference in their Article 28 right to self-government. Abstract judicial review: The federal government, the state governments, or one-quarter of the membership of the Bundestag may bring a state or federal law before the court if they consider it unconstitutional. A well-known example of this procedure was the 1975 abortion decision, which invalidated legislation intended to decriminalise abortion. Concrete judicial review: Article 100(1) of the Basic Law requires any regular court which believes that a law that is necessary to decide a case before it may not be constitutional to suspend the proceedings and bring that law to the Federal Constitutional Court. Article 100(3) requires that state constitutional courts which propose a decision that will overrule or weaken a previous decision by either another state's constitutional court or the Federal Constitutional Court to obtain a decision from the latter. Federal dispute: All federal institutions established by the Basic Law may bring disputes over the scope of their powers, rights and duties before the court. State–federal dispute: The federal government, the state governments, or one-quarter of the members of the Bundestag may ask the court to determine whether a state law conforms to federal law. The Bundesrat, a state government, or a state parliament may ask the court to determine whether a federal law complies with Article 72(2) of the Basic Law – which regards various topics in which both the federal and state governments may pass legislation, but where the federal government's legislative power is restricted to ensuring equivalent living standards across the nation or the preservation of legal or economic unity. If a bill to abrogate a federal law falling in this area (thus returning legislative power on the law's topic to the states) is rejected by the Bundestag, the same organs may appeal to the Court to determine whether the federal law remains necessary. If the federal government believes a state is deficient in executing federal law, Article 84 of the Basic Law provides that either it or the involved state may ask the Bundesrat to determine whether the state is violating the law. The decision of the Bundesrat may be appealed to the court. Any other dispute between a state and the federal government where no other legal recourse exists. Federal election scrutiny: The Bundestag scrutinizes and certifies the results of federal and European Parliament elections. The Constitutional Court hears complaints regarding this certification, or violations of law or civil rights in the conduct of the election. These complaints may be raised within two months of the election by an eligible voter or group of voters, only if it was previously raised to the Bundestag and rejected; a Fraktion of the Bundestag; or one-tenth of the size of the Bundestag set by law (currently 63 members). The court can declare an election invalid in whole or in part due to violations, as happened in Berlin after the 2021 election. "Non-established" (not represented in the Bundestag or any state parliament) political associations, which must apply to the Federal Electoral Committee for legal recognition as a political party and approval to run in a federal election, may appeal a negative decision to the Constitutional Court. A elected Bundestag member who is involuntarily removed from his seat (currently, only by being found ineligible to stand for election during the scrutiny process) may appeal the decision to the Constitutional Court. Impeachment procedure: Impeachment proceedings may be brought against the Federal President for an intentional violation of federal law or the Basic Law with a two-thirds vote of the Bundestag or Bundesrat. The responsible body must submit a complaint to the Constitutional Court detailing the action (or failure to act) which violated the law. The court hears the complaint and decides on the removal of the President; it also has the power to suspend the President from his duties during the proceedings. This requires a two-thirds majority decision. A majority of the Bundestag may impeach any federal judge for "infringing the principles of the Basic Law or the constitutional order of a state". The Constitutional Court hears the complaint, and may order the judge's transfer or retirement. If the court finds the violation is intentional, it may also remove the judge from office. This requires a two-thirds majority decision. Prohibition or hostile classification of a political party: Article 21(2) of the Basic Law gives the Constitutional Court the power to ban political parties that either threaten the existence of Germany or "seek to undermine or abolish the free democratic basic order". A complaint may be filed by the federal government, or by a majority of the Bundestag or Bundesrat. A complaint may be filed by a state government against a party if it only operates in that state. If a party is banned, neither the founding of a new but substantially similar organization nor the repurposing of existing parallel or subordinate organizations as a substitute may take place. Distributing any of the party's material in any medium becomes a crime. Any sitting members in the Bundestag or a state parliament are automatically expelled unless they left the party before the complaint was filed. The court may also decide to confiscate any property belonging to the party and use it for "charitable purposes which are for the public benefit". The court may limit its ban to legally or organizationally independent sections of a party (e.g., individual state or local associations), but it is unclear whether the initial complaint may also be filed against individual sections. This has happened twice: the Socialist Reich Party (SRP), a neo-Nazi group, was banned in 1952, and the Communist Party of Germany (KPD) was banned in 1956. There have been two complaints seeking to ban another neo-Nazi party, The Homeland, then known as the National Democratic Party of Germany (NPD), which failed in 2003 and 2017 respectively. A proposed complaint against Alternative for Germany (AfD) was supported by 124 members of the 20th Bundestag in 2024, but was not advanced to a final vote by the Bundestag Committee for Internal Affairs and subsequently died. Article 21(3), added to the Basic Law in 2017, allows the Constitutional Court to exclude parties "oriented towards undermining or abolishing the free democratic basic order" or the German state (i.e., less stringent than Article 21(2)) from receiving public financing, as well as "any favourable fiscal treatment" of the party or its donors, such as tax exemptions. This type of complaint may be filed by the same institutions as an Article 21(2) complaint. It may be filed as a subsidiary complaint to obtain a ruling under both sub-articles at once. The federal government, Bundestag, and Bundesrat jointly submitted a complaint regarding The Homeland under this article in 2019. The court ruled for it in January 2024, and The Homeland is excluded from public financing until 2030. Decisions under one or both articles require a two-thirds majority vote. Restriction of fundamental rights (Grundrechtsverwirkung): Article 18 of the Basic Law provides for the forfeiture of an individual's basic freedoms of expression (freedom of speech, the press, association, of teaching, or assembly; the right to the secrecy of communication, the right to property, and the right to apply for asylum) if they are used to undermine the democratic order or the German state. The right to human dignity and the freedom of religion are not subject to forfeiture. Upon a complaint from the federal government, a state government, or the Bundestag, the Constitutional Court decides on its validity. The court is free to decide which freedoms are forfeited, to what extent, and for what length of time. This requires a two-thirds majority decision. Two Article 18 complaints have been filed by the federal government, seeking the respective restrictions for a length of time to be determined by the court, and formally decided: Otto Ernst Remer, the founder of the Socialist Reich Party (freedom of speech, association and assembly) in 1952: rejected in 1960 as the court found the government failed to prove that Remer was still involved in politically subversive activities; he had fled the country and gone into hiding after the SRP was banned. Gerhard Frey, editor of the National-Zeitung (freedom of the press) in 1969: rejected in 1974 as the court found the government failed to prove Frey was a future threat to the democratic order.