International law in general — Relation to municipal law — Incorporation of international convention into municipal law — Whether enabling legislation required — Conflict between treaty and subsequently enacted municipal law — Presumption that legislator intends to avoid conflict with international law — The law of Switzerland

State territory — Parts of — Rivers — International rivers — The principle of freedom of navigation on international rivers — Grand Duchy of Baden — Switzerland Convention on Rhine Navigation, 1879 — Convention of Mannheim on Rhine Navigation, 1868 — The law of Switzerland

Treaties — Conclusion and operation of — Operation and enforcement — Necessity for municipal legislation — Incorporation of international conventions into municipal law — Whether enabling legislation required — Conflict between treaty and subsequently enacted municipal law — The law of Switzerland

Treaties — Conclusion and operation of — Effect of municipal legislation — Conflict between treaty and subsequently enacted municipal law — Presumption that legislator intends to avoid conflict with international law — The law of Switzerland

Treaties — Interpretation of — Agencies of interpretation — Objectives of treaty as defined in preamble — Travaux preparatoires — Subsequent practice of political and administrative authorities in Contracting State — The law of Switzerland

Treaties — Interpretation of — Consideration of preparatory work — The law of Switzerland

Treaties — Interpretation of — Principles and rules of interpretation — Clear text — Ordinary meaning — Intention of the parties — Travaux préparatoires — Extensive interpretation — Context — Objectives of treaty — Preamble — Principle of effectiveness — Principle of good faith — Subsequent practice of political and administrative authorities in Contracting State — Incorporation of treaties into municipal law — Whether enabling legislation required — Conflict between treaty and subsequently enacted municipal law — Presumption that legislator intends to avoid conflict with international law — Principle of freedom of navigation on international rivers — Grand Duchy of Baden-Switzerland Convention on Rhine Navigation, 1879 — Convention of Mannheim on Rhine Navigation, 1868 — The law of Switzerland