Blaise Fragione, 38, said when he found out that his partner of 14 years was having an affair "everything broke down," thelocal.fr reported Friday.
The victim of Fragione's 2008 attack told the court Fragione tied him up with cables and used a razor blade to mutilate him.
Fragione faces up to 15 years in prison if found guilty of the charge of aggravated assault accompanied by mutilation.
A verdict in the case is expected shortly officials said.
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