Human rights — European Convention on Human Rights, 1950 — Admissibility of applicants’ claims — Article 1 — Jurisdiction — Article 3 — Prohibition of torture and inhuman or degrading treatment or punishment — Implied duty of non-refoulement — Protocol No 4 to Convention, 1963 — Article 4 of Protocol No 4 — Prohibition of collective expulsion of aliens — Duty to consider cases individually — Article 13 — Right to an effective remedy before a national authority — Effective remedy in relation to Article 3 of Convention and Article 4 of Protocol No 4 requiring potential for suspension of impugned measure — Territorial application of Convention and Protocol No 4 — Application to State conduct on high seas — Whether respondent State violating Articles 3 and 13 of Convention and Article 4 of Protocol No 4

Relationship of international law and municipal law — Treaties — Interpretation — European Convention on Human Rights, 1950 — Protocol No 4 to Convention, 1963 — Convention relating to the Status of Refugees, 1951 — Principle of non-refoulement — Vienna Convention on the Law of Treaties, 1969 — United Nations Convention on the Law of the Sea, 1982 — Italian Navigational Code 1942