Carlos Moran was working for the Argentinean regulatory agency in 2000 when he says he discovered numerous irregularities in Siemens' bid to make the country's national ID cards, and told his boss about them.
He claims his boss was bribed by the company to ignore his reports, and that he subsequently threatened to make his allegations public.
Both his boss and Siemens' Argentinean branch then allegedly attempted to prevent Moran from carrying out his threat - by hiring thugs to threaten him with a weapon, beat him up, force his car off the road, and verbally abuse him on the phone.
Moran says he was threatened with kidnapping and having his house set on fire, and that his family has been traumatized by the campaign - his young son reportedly started to stutter and is still undergoing therapy.
Moran is now demanding compensation from Siemens in a Miami court, on the grounds that the company is registered at the New York Stock Exchange and has around 60,000 US employees.
Last December, the US Securities and Exchange Commission (SEC) charged eight former Siemens executives with conspiring to bribe Argentinean government officials to land the $1 billion ID card contract.