The contribution examines the legal issues arising from the exclusion of ne bis in idem principle between Canon and Italian Law, as most recently reaffirmed by the Court of Cassation with sentence no. 34576 of 2021. The paper calls for a hermeneutic study of art. 23 par. 2 of the Lateran Treaty to guarantee effectively the principle of proportionality of the overall sanctioning treatment also with respect to clerics, subject to the double sanction of State and Canon criminal law for the idem factum. It also proposes the identification of possible forms of inter-ordination to arrive at a valorisation of the canonical sanction in the concrete determination of the subsequent State sanction, similarly to what is provided for by the new canon 1344 Codex Iuris Canonici.