Mihail Moisis, a petty officer on the MV Island Skipper, died on the ship while navigating in Brazilian waters in a voyage from Rio de Janeiro, Brazil, to Buenos Aires, Argentina. The master notified the Brazilian authorities, who sent a doctor on board to certify the death. The ship continued its voyage. Upon arrival in Buenos Aires, the death was reported to the State Court for investigation.

The State Court declined jurisdiction in favour of the Federal Courts, based on the rules that establish the exceptional jurisdiction for crimes committed on the high seas or in places where the national government exercises exclusive authority. The Federal Court rejected jurisdiction over the case, holding that the event neither affected federal interests or the provision of the service of a national establishment, nor compromised the safety of fluvial traffic. The Provincial Court insisted on its lack of jurisdiction to undertake the investigation, alleging that crimes committed on the high seas must be decided by the Sectional Courts of the first port where the ship calls. This conflict of jurisdiction was submitted to the Supreme Court (SC) for its decision.

Held: The SC assigned the jurisdiction to the Federal Court.

The SC adopted the opinion of the Attorney-General. The Attorney-General stated that it must be determined whether the Republic of Argentina has jurisdiction over the event, considering that it occurred in the territorial waters of the Federative Republic of Brazil. In this regard, the United Nations Convention on the Law of the Sea 1982 (UNCLOS), ratified by Argentina, establishes in art 27 that 'the criminal jurisdiction of the coastal State should not be exercised on board a foreign ship passing through the territorial sea to arrest any person or to conduct any investigation in connection with any crime committed on board the ship during its passage'. This article is found in Pt II of the Convention relating to the right of innocent passage. Article 18.2 states that the 'passage shall be continuous and expeditious. However, passage includes stopping and anchoring, but only in so far as the same are incidental to ordinary navigation or are rendered necessary by force majeure or distress or for the purpose of rendering assistance to persons, ships or aircraft in danger or distress.'

According to these provisions, the jurisdiction of the coastal State is excluded, because the operation of the ship in the coastal State's territorial waters was limited to innocent passage. The participation of the Brazilian authorities was limited to providing assistance by sending a doctor who arrived on the ship in a helicopter, without having the ship call into any port. Therefore, the courts of the port of arrival have jurisdiction in this case. The ship's master did not request the further assistance of the authorities of the coastal State, which would have been one of the exceptions to the principle of exclusion from criminal jurisdiction on board ships in cases of innocent passage (article 27.1.c). Rather, the ship continued the voyage to the destination port, where the master required the intervention of the Argentinian authorities.

The procedural rules, following the aforementioned international law rules, assign jurisdiction in the case of crimes committed on the high seas to the Sectional Court of the first port the ship calls into after the incident. In this case, the emergency reported on the ship that required its momentary detention in Brazilian jurisdictional waters can be equated to a situation that occurred on the high seas to establish federal jurisdiction. As matters of admiralty, maritime and aviation jurisdiction are within the exclusive cognisance of the federal justice system, the Federal Court must continue with these proceedings.