translate English to French: The unlawful character of an expulsion may result from the violation of (1) a rule contained in an international treaty to which the expelling State is a party; (2) a rule of customary international law; or (3) a general principle of law.
Convention (C143) sur les migrations dans des conditions abusives et sur la promotion de l'égalité de chances et de traitement des travailleurs migrants, Genève, 24 juin 1975, Nations Unies, Recueil des Traités, vol.