1. Freedom of Navigation

Freedom of Navigation

Concept

In the territorial sea, freedom of navigation is addressed through the rules on passage by foreign ships. Passage concerns navigation through that sea, while innocent passage depends on whether the ship’s activities prejudice the coastal State’s peace, good order, or security. The coastal State, in turn, must not hamper innocent passage except in accordance with UNCLOS. (Art. 18, UNCLOS)¹ (Art. 19, UNCLOS)² (Art. 24, UNCLOS)³

Governing provisions

UNCLOS Article 18 defines passage; Article 19 determines when passage is innocent; and Article 20 prescribes how submarines and other underwater vehicles must navigate in the territorial sea. Articles 22 and 24 address sea lanes and coastal-State duties, respectively. Article 27 addresses criminal jurisdiction on board a foreign ship during passage. (Art. 18, UNCLOS)¹ (Art. 19, UNCLOS)² (Art. 20, UNCLOS)⁴ (Art. 22, UNCLOS)⁵ (Art. 24, UNCLOS)³ (Art. 27, UNCLOS)⁶

Requisites / Rules

• Passage may involve traversing the territorial sea without entering internal waters, or proceeding to or from internal waters, a roadstead, or a port facility as specified in Article 18. It must be continuous and expeditious, subject to the permitted stopping and anchoring discussed below. (Art. 18, UNCLOS)¹
• Passage remains innocent so long as it is not prejudicial to the coastal State’s peace, good order, or security and conforms to UNCLOS and other rules of international law. Activities that defeat innocence include weapons exercises, intelligence collection prejudicial to defense or security, fishing, research or surveys, and activities without a direct bearing on passage. (Art. 19, UNCLOS)²
• In the territorial sea, submarines and other underwater vehicles must navigate on the surface and show their flag. (Art. 20, UNCLOS)⁴
• Where necessary for navigational safety, the coastal State may require ships exercising innocent passage to use designated sea lanes or traffic separation schemes. It must clearly indicate them on charts given due publicity. (Art. 22, UNCLOS)⁵

Distinctions

Do not equate passage with innocent passage: Article 18 describes the navigation and its purpose, while Article 19 tests the conduct of the foreign ship. A voyage fitting Article 18 may lose its innocent character through an activity listed in Article 19. (Art. 18, UNCLOS)¹ (Art. 19, UNCLOS)²

Key doctrines

The coastal State may not impose requirements that practically deny or impair innocent passage, or discriminate against ships by State or by the cargoes they carry to, from, or on behalf of a State. It must also give appropriate publicity to known dangers to navigation in its territorial sea. (Art. 24, UNCLOS)³

Exceptions

Stopping or anchoring may still form part of passage when incidental to ordinary navigation, required by force majeure or distress, or undertaken to assist persons, ships, or aircraft in danger or distress. Separately, Article 27 specifies circumstances in which the coastal State may exercise criminal jurisdiction on board a passing foreign ship for a crime committed during passage, including when the crime’s consequences extend to the coastal State. (Art. 18, UNCLOS)¹ (Art. 27, UNCLOS)⁶

Bar tip

Analyze a territorial-sea problem in sequence: identify passage, test its innocence against the ship’s acts, then assess the applicable coastal-State measure. (Art. 18, UNCLOS)¹ (Art. 19, UNCLOS)² (Art. 24, UNCLOS)³