Article 706-12 of the French Code of Criminal Procedure
If the victim or the victim’s heirs bring a civil action before the criminal court or bring an action against the persons responsible for the damage, they must indicate, at all stages of the proceedings, whether they have referred the matter to the commission set up by Article 706-4 and whether, if so, it has awarded them compensation. Failing this indication, the nullity of the judgment as regards its civil…