Germany's Constitutional Court and the euro

(KARLSRUHE) - Germany's Constitutional Court holds the fate of the euro in its hands on Wednesday as it rules on the legality of key weapons in the fight against the near three-year debt crisis.

The court has a history of ruling in favour of steps towards greater European integration but insisting the German parliament has more say in the decisions taken.

The court based in the western city of Karlsruhe consists of eight judges, instantly recognisable by their scarlet robes and hats.

Four of the eight judges, who must be at least 40 years old, are chosen by the lower house of parliament and the other four by the upper house for a non-renewable 12-year term.

The court can slap down laws made in parliament if it believes they contravene Germany's "Grundgesetz" or "Basic Law", the constitution drafted for then West Germany in 1949 by the victorious Allied powers after World War II.

German citizens can bring cases before the court if they believe their constitutional rights to be infringed.

Following is a summary of the court's last three major decisions on European policy:

-- February 28, 2012: Court slaps down "fast-track" euro crisis response panel. The court rejected a plan to set up a core group of nine German lawmakers that could rapidly and in secret take decisions on providing aid to crisis-stricken countries. They said this infringed the rights of the other MPs in parliament and that budgetary policy was "the responsibility of the whole Bundestag" (lower house).

-- September 7, 2011: Court clears aid to Greece but hands MPs more say. The court said that a proposed multi-billion EU-IMF bailout package conformed with the Basic Law but said that the Bundestag must give its approval for all future bailout deals, slowing down the procedure and giving German lawmakers an effective veto.

-- June 30, 2009: Court suspends EU's Lisbon Treaty. The court delays Germany's ratification of the Lisbon Treaty designed to streamline decision-making until a law protecting national parliamentary powers is passed. However, it threw out the complaint that the Treaty handed too many powers to Brussels and said it was consistent with the Basic Law.