In November 1996, the Praetor of Genoa decided that Salvatore Mistretta (SM) and Matteo Peralta (MP), as masters of the Italian-flagged vessel Acrux, did not commit a crime under Italian criminal law when discharging polluting substances in international waters.

The Chief Prosecutor of the Court of Appeal of Genoa appealed in cassation. The united Sections of the Court of Cassation decided the case, because of a conflict of jurisprudence on the issue.

Held: The appeal is dismissed.

The Court noted that the predominant view in the jurisprudence supported the absolute prohibition at Italian law of all polluting substances from ships in national waters and on the high seas. This view was based on the assumption that MARPOL contains an obligation on the part of contracting States not to adopt more permissive measures to fight pollution from ships, but allows States to adopt stricter standards. However, the Court did not find a legal basis for this view. It emphasised that the stricter standard prevailed under the Italian Civil Code in light of the juxtaposition between Italian law and MARPOL. However, the stricter standard had no relevance under the Italian Criminal Code.

Furthermore, the Court recalled art 211.2 UNCLOS, which provides that:

States shall adopt laws and regulations for the prevention, reduction and control of pollution of the marine environment from vessels flying their flag or of their registry. Such laws and regulations shall at least have the same effect as that of generally accepted international rules and standards established through the competent international organization or general diplomatic conference. 

The Court pointed out that art 211.2 UNCLOS does not authorise States to modify the MARPOL provisions by adopting stricter legal measures than those provided for in Annex II MARPOL.

In conclusion, the Court decided that SM and MP had not committed a crime, as they complied with MARPOL Annex II procedures when discharging the polluting substances in international waters.