Innocent Passage, and Straits

Notice two things. The list is about what the ship does, not about what it is or what it carries: a cargo of weapons is not itself prejudicial, using them is. And paragraph (l) is a catch-all, which is what stops the list being exhaustive in practice.

Article 20. In the territorial sea, submarines and other underwater vehicles are required to navigate on the surface and to show their flag. A submerged submarine is therefore not in innocent passage.

What the coastal State may do

Article 21. The coastal State may adopt laws and regulations relating to innocent passage in respect of the safety of navigation and the regulation of maritime traffic, the protection of navigational aids and facilities, the protection of cables and pipelines, the conservation of living resources, the prevention of infringement of its fisheries laws, the preservation of the environment, marine scientific research and hydrographic surveys, and the prevention of infringement of its customs, fiscal, immigration or sanitary laws. Such laws must not apply to the design, construction, manning or equipment of foreign ships unless they give effect to generally accepted international rules.

Article 22 allows sea lanes and traffic separation schemes. Article 24 imposes duties on the coastal State: it shall not hamper innocent passage, shall not impose requirements having the practical effect of denying or impairing the right, shall not discriminate against the ships of any State, and shall give appropriate publicity to any danger to navigation of which it has knowledge.

Article 25. The coastal State may take the necessary steps in its territorial sea to prevent passage which is not innocent, may prevent breaches of the conditions of admission to internal waters, and may, without discrimination in form or in fact among foreign ships, suspend temporarily in specified areas of its territorial sea the innocent passage of foreign ships if such suspension is essential for the protection of its security, such suspension taking effect only after having been duly published.

Article 26. No charge may be levied upon foreign ships by reason only of their passage, and charges for specific services rendered must be levied without discrimination.

Article 27, criminal jurisdiction. 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 conduct any investigation in connection with a crime committed on board during its passage, save only where (a) the consequences of the crime extend to the coastal State; (b) the crime is of a kind to disturb the peace of the country or the good order of the territorial sea; (c) the assistance of the local authorities has been requested by the master or by a diplomatic agent or consular officer of the flag State; or (d) such measures are necessary for the suppression of illicit traffic in narcotic drugs or psychotropic substances.

Article 28 restricts civil jurisdiction: the coastal State should not stop or divert a foreign ship passing through the territorial sea for the purpose of exercising civil jurisdiction in relation to a person on board.

Article 29 defines a warship, and articles 30 and 31 deal with warships that do not comply: the coastal State may require the warship to leave the territorial sea immediately, and the flag State bears international responsibility for any loss or damage.

India: section 4 of the Maritime Zones Act 1976 governs the passage of foreign ships through India's territorial waters.

Two provisions about particular ships

Article 23. Foreign nuclear-powered ships and ships carrying nuclear or other inherently dangerous or noxious substances shall, when exercising the right of innocent passage, carry documents and observe special precautionary measures established for such ships by international agreements. So the coastal State's protection against these ships is documentary and precautionary, and does not extend to excluding them.

Article 32. With the exceptions contained in subsection A and in articles 30 and 31, nothing in the Convention affects the immunities of warships and other government ships operated for non-commercial purposes. That is the law of the sea's cross-reference to [Immunity from Jurisdiction]: a warship in the territorial sea may be required to leave, and it may not be boarded, arrested or proceeded against.

Straits, and the case MU names

Facts. Corfu Channel Case (United Kingdom v. Albania), ICJ Reports 1949, page 4, judgment of 9 April 1949. On 22 October 1946 two British cruisers and two destroyers entered the North Corfu Strait through a channel in Albanian waters that had been swept in 1944 and check-swept in 1945 and was regarded as safe. The destroyer Saumarez struck a mine off Saranda and was gravely damaged; the Volage, sent to help and towing her, struck another. Forty-five British officers and sailors were killed and forty-two wounded. An Albanian battery had fired on two British cruisers in the same waters on 15 May 1946, after which the United Kingdom had asserted a right of innocent passage through straits and Albania had replied that foreign warships had no right to pass without prior authorisation. On 12 and 13 November the British Navy swept the channel against Albania's expressed refusal of consent and cut twenty-two moored mines.

Held on passage. By fourteen votes to two, the passage of 22 October did not violate Albanian sovereignty. Albania's claim to make the passage of ships conditional on prior authorisation conflicts with the generally admitted principle that States, in time of peace, have a right to send their warships through straits used for international navigation between two parts of the high seas, provided that the passage is innocent. The Corfu Strait belongs geographically to that category even though it is only of secondary importance, in the sense that it is not a necessary route between two parts of the high seas, and irrespective of the volume of traffic. The passage was innocent both in its principle, since it was designed to affirm a right which had been unjustly denied, and in its methods of execution, which were not unreasonable in view of the firing from the Albanian battery on 15 May.

Held on the minesweeping. Unanimously, the operation of 12 and 13 November did violate Albanian sovereignty. It was executed contrary to the clearly expressed wish of the Albanian Government, did not have the consent of the international mine clearance organisations, and could not be justified as an exercise of the right of innocent passage. The Court could only regard the alleged right of intervention as the manifestation of a policy of force which cannot find a place in international law, and it could not accept self-help either, since between independent States the respect for territorial sovereignty is an essential foundation for international relations. The declaration that the sweep violated Albanian sovereignty was itself held to constitute appropriate satisfaction.

Why it matters. It establishes the right of passage of warships through straits used for international navigation, on a test of geography rather than of traffic volume, and it is the leading modern rejection of intervention and self-help. Its responsibility holding is worked in [State Responsibility].

Transit passage: the Convention's answer

The Convention went further than Corfu Channel, and the reason is the twelve-mile territorial sea. Once States could claim twelve miles, straits less than twenty-four miles wide became territorial sea throughout, and a right of innocent passage, which can be suspended under article 25(3), would have let coastal States close them. Maritime powers would not accept that, and Part III is the compromise.

Article 37. Part III's transit passage regime applies to straits used for international navigation between one part of the high seas or an exclusive economic zone and another part of the high seas or an exclusive economic zone.

Article 38. All ships and aircraft enjoy the right of transit passage, which shall not be impeded. Transit passage means the exercise of freedom of navigation and overflight solely for the purpose of continuous and expeditious transit.

Three ways it is stronger than innocent passage. It covers aircraft, which innocent passage does not. It does not require submarines to surface. And it is not suspendible: article 44 provides that States bordering straits shall not hamper transit passage and that there shall be no suspension of transit passage.

Three provisions define the regime's edges. Article 34 provides that the regime of passage through straits established in Part III shall not in other respects affect the legal status of the waters forming such straits or the exercise by the bordering States of their sovereignty or jurisdiction over those waters and their bed, subsoil and airspace. Article 35 states the scope of the Part, preserving internal waters within the strait, the status of waters beyond the territorial seas as exclusive economic zone or high seas, and regimes in straits regulated by long-standing international conventions in force specifically relating to them. Article 36 takes a strait out of the transit passage regime altogether where there exists through it a route through the high seas or through an exclusive economic zone of similar convenience with respect to navigational and hydrographical characteristics, in which case the other Parts apply.

Article 40 forbids foreign ships in transit passage, including marine scientific research and hydrographic survey ships, to carry out any research or survey activities without the prior authorisation of the States bordering the strait. Article 43 provides that user States and States bordering a strait should by agreement cooperate in the establishment and maintenance of necessary navigational and safety aids and other improvements in aid of international navigation, and in the prevention, reduction and control of pollution from ships.

Article 39 sets out the duties of ships and aircraft in transit: proceed without delay, refrain from any threat or use of force against the sovereignty, territorial integrity or political independence of States bordering the strait, and refrain from any activities other than those incident to their normal modes of transit. Articles 41 and 42 allow sea lanes and laws and regulations. Article 45 preserves non-suspendible innocent passage in straits excluded from the transit passage regime.

A worked example

A foreign warship enters State CC's territorial sea, submerged, and surfaces four miles from the coast. It then launches a helicopter, photographs a naval base, and anchors for two days. Later it passes through a strait two miles wide connecting two parts of the high seas, and State CC announces that the strait is closed for a month of exercises.

Submerged entry. Article 20 requires submarines and other underwater vehicles in the territorial sea to navigate on the surface and show their flag. Entering submerged is not innocent passage.

Launching the helicopter. Article 19(2)(e): the launching, landing or taking on board of any aircraft is expressly prejudicial.

Photographing the base. Article 19(2)(c): any act aimed at collecting information to the prejudice of the defence or security of the coastal State.

Anchoring for two days. Article 18(2) requires passage to be continuous and expeditious, and permits stopping and anchoring only where incidental to ordinary navigation, rendered necessary by force majeure or distress, or for rendering assistance. Two days of anchoring is not passage at all, and article 19(2)(l) catches any other activity not having a direct bearing on passage.

What may State CC do? Article 25(1): take the necessary steps in its territorial sea to prevent passage which is not innocent. If the ship is a warship that does not comply with its laws and disregards a request for compliance, articles 30 and 31 let State CC require it to leave immediately and make the flag State internationally responsible for loss or damage.

Closing the strait. This is where the answer turns. If the strait is used for international navigation between two parts of the high seas, article 38 gives all ships and aircraft the right of transit passage and article 44 provides that there shall be no suspension of it. State CC's announcement is therefore unlawful. Had the water been ordinary territorial sea rather than a strait, article 25(3) would have permitted temporary suspension of innocent passage in specified areas, without discrimination, where essential for security and after due publication.

And if a warship had been refused passage through the strait outright? Corfu Channel: States in time of peace have a right to send their warships through straits used for international navigation between two parts of the high seas, provided the passage is innocent, and a requirement of prior authorisation conflicts with that principle.

Distinctions table

What it does NOT mean

Innocent passage is not a licence to stop. Passage must be continuous and expeditious, and anchoring is permitted only in the narrow cases in article 18(2).

A ship's cargo does not make passage non-innocent. Article 19(2) lists activities, not cargoes or ship types.

The coastal State cannot charge for passage. Article 26 forbids charges levied by reason only of passage.

Suspension must be temporary, published and non-discriminatory, and it is unavailable in straits.

Corfu Channel did not decide the volume of traffic matters. The Court held the strait qualified even though it was of secondary importance and not a necessary route.

Limits and criticism

Whether warships enjoy innocent passage is still disputed. Article 17 says ships of all States, and Part II section 3 subsection C deals expressly with warships, which suggests they are included. A number of States nevertheless require prior notification or authorisation for warships, and their declarations under article 310 say so, while the maritime powers reject those requirements. The Convention did not settle it, and Corfu Channel decided the point only for straits.

Article 19(2)(l) undermines the list. A catch-all for any other activity not having a direct bearing on passage restores much of the discretion that the enumeration was meant to remove.

Transit passage exists because of a bargain, not because of principle. It was the price of the twelve-mile territorial sea, and its content, particularly the freedom of submerged transit and overflight, is asserted more clearly by the maritime powers than by the States bordering the straits.

Quick revision

Article 17: ships of all States, coastal or land-locked, enjoy innocent passage through the territorial sea.

Article 18: passage is navigation to traverse the territorial sea or to proceed to or from internal waters; continuous and expeditious; stopping and anchoring only if incidental to ordinary navigation, or necessary by force majeure or distress, or to render assistance.

Article 19(1): innocent so long as not prejudicial to the peace, good order or security of the coastal State. 19(2): twelve listed activities, from the threat or use of force to (l) any other activity not having a direct bearing on passage.

Article 20: submarines must navigate on the surface and show their flag.

Article 21 coastal State laws; 22 sea lanes; 24 duties not to hamper, not to discriminate, to publicise dangers; 25 prevent non-innocent passage, and temporary suspension for security, published, without discrimination; 26 no charge for passage alone; 27 criminal jurisdiction only in four cases; 28 civil jurisdiction restricted; 29 to 32 warships.

Corfu Channel (ICJ Reports 1949, page 4): States in time of peace may send warships through straits used for international navigation between two parts of the high seas, provided passage is innocent; the strait qualified though of secondary importance; the minesweeping violated sovereignty, and intervention is the manifestation of a policy of force which cannot find a place in international law.

Part III, transit passage: article 37 scope; 38 all ships and aircraft, freedom of navigation and overflight for continuous and expeditious transit; 39 duties; 44 no suspension; 45 non-suspendible innocent passage where transit passage does not apply.

Test yourself

1. When is passage innocent?

Article 19(1) provides that passage is innocent so long as it is not prejudicial to the peace, good order or security of the coastal State, and must take place in conformity with the Convention and other rules of international law. Article 19(2) makes this concrete by listing twelve activities which render passage prejudicial, including any threat or use of force, weapons exercises, information gathering to the prejudice of the coastal State's defence or security, propaganda, launching or taking on board aircraft or military devices, loading or unloading contrary to customs, fiscal, immigration or sanitary laws, wilful and serious pollution, fishing, research or survey activities, interference with communications, and any other activity not having a direct bearing on passage.

2. Distinguish innocent passage from transit passage.

Innocent passage applies in the territorial sea under article 17, benefits ships only, requires submarines to navigate on the surface and show their flag under article 20, and may be suspended temporarily in specified areas for security reasons under article 25(3). Transit passage applies in straits used for international navigation between one part of the high seas or exclusive economic zone and another, under article 37, benefits ships and aircraft under article 38, permits submarines to transit in their normal mode, and may not be suspended at all under article 44. Transit passage exists because a twelve-mile territorial sea turned narrow straits into territorial sea throughout, and the maritime powers would not accept a suspendible right there.

3. State the holding of Corfu Channel on passage.

By fourteen votes to two, the passage of 22 October 1946 did not violate Albanian sovereignty. Albania's claim to make passage conditional on prior authorisation conflicts with the generally admitted principle that States, in time of peace, have a right to send their warships through straits used for international navigation between two parts of the high seas, provided the passage is innocent. The Corfu Strait belonged geographically to that category even though it was only of secondary importance, in the sense of not being a necessary route between two parts of the high seas. The passage was innocent both in principle, being designed to affirm a right unjustly denied, and in its methods, which were not unreasonable given the firing from the Albanian battery on 15 May.

4. May a coastal State arrest a person on board a foreign ship in innocent passage?

Article 27(1) provides that its criminal jurisdiction should not be exercised on board a foreign ship passing through the territorial sea to arrest any person or conduct any investigation in connection with a crime committed on board during its passage, save only in four cases: where the consequences of the crime extend to the coastal State; where the crime is of a kind to disturb the peace of the country or the good order of the territorial sea; where the assistance of the local authorities has been requested by the master or by a diplomatic or consular officer of the flag State; or where the measures are necessary for the suppression of illicit traffic in narcotic drugs or psychotropic substances.

5. Can a coastal State close its territorial sea to foreign shipping?

Not generally. Article 24 forbids it to hamper innocent passage, to impose requirements having the practical effect of denying or impairing the right, or to discriminate against the ships of any State. Article 25(3) permits only a temporary suspension, in specified areas of the territorial sea, without discrimination in form or in fact among foreign ships, where suspension is essential for the protection of its security, and only after due publication. In a strait to which transit passage applies there is no power of suspension at all, article 44 providing that there shall be no suspension of transit passage.

6. Do warships enjoy innocent passage? Explain the difficulty.

The better view is that they do. Article 17 confers the right on ships of all States without qualification, and Part II contains a subsection dealing expressly with warships, which would be unnecessary if they were outside the regime; articles 30 and 31 give the coastal State a remedy against a non-complying warship, which again presupposes that it may be there. The difficulty is that a number of States require prior notification or authorisation for warships and have said so in declarations under article 310, while the maritime powers reject those requirements as inconsistent with article 17. The Convention did not settle the question, and Corfu Channel settled it only for straits used for international navigation, where it held a requirement of prior authorisation to be inconsistent with the right of passage.