The alleged mastermind behind the »Ibiza video« can be extradited to Austria.
The Federal Constitutional Court rejected an urgent application from the man on Monday.
According to the resolution from Karlsruhe, he had "failed to substantiate the fact that he was being politically persecuted in the Republic of Austria and that a fair trial was not awaiting him there (...)".
The actual constitutional complaint is still pending, but a decision can be taken after extradition.
It is unclear when the man will have to leave Germany.
The urgent application was directed against a decision of the Berlin Chamber Court, which had declared extradition admissible.
The 40-year-old private detective, who was wanted with a European arrest warrant, was arrested in Berlin in December.
On Friday he was questioned in the Bundestag investigative committee about the Wirecard accounting scandal, to which he had offered himself as a witness.
The video published in May 2019 had led to the overthrow of the government of the conservative ÖVP and right-wing FPÖ in Austria.
The then FPÖ boss Heinz-Christian Strache appeared susceptible to corruption on the video that was secretly recorded in Ibiza.
Icon: The mirror
kev / dpa