Translate the following English sentence to French:
"A third element is that it is applied to legal persons, when they are responsible, as it is they, rather than individuals, that commit the vast majority of serious environmental crimes."
Troisièmement, cette proposition identifie les personnes morales comme responsables, l' immense majorité des infractions graves au détriment de l' environnement étant le fait des personnes morales et non physiques.