How did an accused torturer end up teaching at the Sorbonne?

Mario Sandoval charged with dictatorship-era crimes in Argentina - so how could he have worked undetected at a top French university?

Mario Sandoval had been living in France for 14 years when he became a lecturer at the Institute of Latin American Studies (IHEAL) at the Sorbonne in Paris.

The Argentinian security specialist was in his mid-40s, spoke good French and had recently obtained French citizenship. His credentials were impeccable - he'd spent the previous five years teaching international relations at another Paris institute, the Universiti(C) Marne-la-Valli(C)e - and he soon became a valued asset at the Sorbonne.