Klaus Zumwinkel was the highest profile among hundreds of wealthy Germans caught up in the tax investigation in February, 2008. But the investigation was controversial from the start, as German authorities paid a former employee of a Liechtenstein bank 4.2 million euros ($5.4 million) for a CD containing the names of prominent account-holders.

The case shone a bright light on Liechtenstein's banking practices, which have a tradition of secrecy. The tiny country has become a center for people to invest their money while drawing little attention to the fact.

Zumwinkel, 64, resigned from his post at Deutsche Post after police raided his villa following the procurement of the bank data. Reports say he was accused of avoiding 1.2 million euros in tax he was obligated to pay from investment profits of 2.5 million euros earned in Liechtenstein.

The scandal prompted a plethora of countries to open their own investigations into connections between Liechtenstein bank accounts and citizens.