Though he has been a near mythic figure in Germany since the 1980s, there was no known photograph of him in circulation until 2000. He offered no opening statement to the court. His lawyers claimed he cannot mount a "proper defence" because he is still subject to secrecy agreements and cannot testify without the express permission of the German Government.
A freelance agent rather than a government intelligence officer, he started out as a private detective, founding his own agency at the age of 20.
He is believed to have worked extensively undercover for Germany's BND intelligence service and the Bundeskriminalamt, the country's national police CID. He claims to have also worked for various other Western intelligence agencies, but the shadowy nature of the work makes the details impossible to confirm.
The case against him centres on various offshore accounts he allegedly holds in the Bahamas, Luxembourg and elsewhere. Proscutors say he failed to disclose the existence of the accounts to the German tax authorities. His name has also been connected with various offshore shell companies listed in the "Panama Papers".
Lawyers for Mauss have contended the accounts were set up by various intelligence agencies and that he used the money for operations including hostage releases. If convicted, Mauss faces several years in prison.
