Historically there were high seas and territorial seas. States enjoyed certain rights in their territorial seas. The high seas were open to all. The Law of the Sea has developed considerably over the last 50 years. New areas and zones are recognised with reference to resources.
The International Law Commission drafted the first Draft Articles on the Law of the Sea (UNCLOS I) in 1958. It has produced four Geneva Conventions on the Law of the Sea. This is based on customary law but has been developed very considerably.
UNCLOS II was drafted to deal with related and unresolved issues from UNCLOS I. The Third US Conference on the Law of the Sea met between 1974 and 1982 and the 1982 Convention on the Law of the Sea was adopted. By the 1990s it has been ratified by over 60 countries required to give it force. However, it was not accepted by certain key developed states.
An implementation agreement was made in 1994 amending the Convention to make it acceptable to a more states. This has now been accepted by 160 states, including the European Union. The Implementation Agreement has been accepted by 138 states. Some states are party to the 1982 Convention whereas most are party to the Convention and the 1994 LOSC. Some parts of the Convention are framework in nature and there are further Conventions which fill in and supplement relevant issues.
A basic principle is the extent of state jurisdiction for various purposes over adjoining seas. Generally, coastal states have the greatest jurisdictions. In internal waters, the state is sovereign. This includes lakes, harbours and seas outwards to base lines. These baselines, represents complete internal sovereignty.
External sovereignty in parts of the sea is measured from the baseline. Islands may have baselines and may create legal maritime zones. Rocks which cannot sustain human habitation or economic life have no exclusive economic zone or continental shelf.
The normal baseline for measuring the breadth of the territorial sea is the low waterline along the coast shown on appropriate charts officially recognised by the coastal state. A number of rules and principles apply to construction of baselines.
Straight lines may be drawn if the coastline is deeply intended or cut into or if there is a fringe of islands along the coasts in its immediate vicinity. Absent this, the above principle applies. Although straight lines may be drawn, principles apply as to how they are to be drawn. They must not depart to any appreciable extent from the general direction of the coast.
Sea areas lying within the lines must be sufficiently closely linked to the land domain to be subject to the regime of internal waters. Local economic interest may be taken into account in establishing particular baselines. This is relevant in that it reflects the fact of full internal sovereignty within the baselines.
Baselines may be contentious, where a narrow bay opens into a broad area of water. In this context, an arc is drawn at the entrance to the bay and the semicircle is compared with the area of water within the bay. If it is less than the semicircle, it is a bay. If the area is greater, it is not a bay for the purpose of the Law of the Sea.
A closing line is then drawn if the distance between the entrance points is less than 24 nautical miles. A closing line may be set between them. If the lines are greater than 24 nautical miles, a closing line of up to that length can be drawn within the bay so as to enclose the maximum area of water possible with a line of that length.
Where a bay coastline delineates two states, more complex issues arise. The Law of the Sea has no specific provisions.
The Law of the Sea provisions do not apply to historic bays claimed by coastal states as part of their internal waters for a long-standing basis with acquiescence of third-party states. This is an alternative method of delineating baselines.
The matter of internal jurisdiction is more difficult with states which comprise of groups of islands and coastal archipelagoes. Prime examples are Indonesia and Philippines.
Archipelagic States are those defined as a group of islands or part of islands and their interconnecting water. The UK is an archipelago for this purpose. However not all archipelagic states may construct am archipelagic baseline.
The main islands must be linked to the group. No baseline may be more than 100 nautical miles. An exception to this is that 3% may be up to 125 nautical miles in length. They must follow the general configuration of the island grouping. The ratio of water to land within the baselines must be not less, between 1 to 1 and 9 to 1.
According to these criteria, some large islands which are technically archipelagic, including Japan and the UK and have very small and distant islands may not draw archipelagic baselines. The principles are not accepted by all states and customary law and acquiescence may take precedence in some cases.
Waters within the archipelagic baselines are not internal waters but are archipelagic waters. Special rules apply in terms of fishing and navigation.
Although the matter was never fully settled, the historical position was that states exercised sovereign jurisdiction to three miles. Many states argued for extension of this limit for both security purposes and for exploitation of resources. The issue was not determined under the First and Second Conventions.
By the time of the UNCLOS III, an extension to 12 nautical miles was accepted. LOSC expressly recognises a territorial sea up to 12 nautical miles and almost all states have accepted it. This area is the subject of state sovereignty as to both air space and the submarine area.
States have both rights and duties in respect of their territorial seas. They must maintain navigational aids and may be liable for damage caused in consequence of not so doing.
Within internal waters, states have full jurisdiction. They need not allow foreign vessels to enter except if they are in distress or in areas where there was customary rights of innocent passage before establishment of baselines. Subject to this, the adjoining state may impose conditions on entry into the waters.
Within internal waters, domestic legislation applies and may be enforced. Although there is a right to enforce, local or states may exercise restraint in so doing. They may commonly limit jurisdiction to actions within the confines of their ports.
The prevalent view is that the jurisdiction of a state applies to its territorial sea. This is subject to limitations imposed by international law and Convention. For example, vessels are entitled to exercise the right of innocent passage.
The Law of the Sea Convention urges states not to exercise jurisdiction, unless there are consequences for state. For example, there may be a breach of the peace or good order, assistance is requested or it is necessary to suppress illicit drugs traffic.
If the vessel has left the state, lesser restraint is required. The state must have regard to the interest of navigation in deciding whether to arrest a ship within its territorial seas.
States are urged not to exercise civil jurisdiction in their territorial seas. Vessels should not be an arrested and stopped to exercise jurisdiction in civil matters over an individual or in rem. It should be referable to the activities of the vessel.
States may not arrest foreign warships or ships being used for governmental purposes owned by other states. They may be required to leave territorial waters immediately using the requisite degree of force if appropriate.
Because the limits of territorial jurisdiction on the seas between the high sea and the coastal states jurisdiction is an arbitrary limit, states were allowed to arrest vehicles outside of territorial seas for offences committed within it or which were reasonably suspected to be committed within it.
States may prevent or punish infringements of certain laws in a zone up to 24 nautical miles, from baselines, a so-called contiguous zone. These include customs, fiscal, immigration and sanitary regulations. Punishment in this context, allows vessels which have committed an offence within territorial waters to be arrested outside of territorial waters.
Ships generally enjoy a right of innocent passage through the territorial seas of adjoining states. Passage in this context refers to travelling in a continuous, expeditious fashion. Stops in the ordinary course of navigation or as a result of force majeure are allowed. Innocent passage implies that it is not prejudicial to peace, good order, or security of the adjoining state. The opinion of the costal state is not conclusive. They must not take arbitrary action.
Infringements by foreign fishing vessels of local legislation regarding fishing is not innocent for this purpose. Submarines must navigate on the surface and show their flags in order to exercise the right. This is on the basis that these actions are not passable with innocent passage at all.
In the context of the right of free passage, the Law of the Sea Convention provides that the coastal states may legislate in respect of navigational safety pipelines and cables, conservation of living resources, fishery laws, preservation of the environment, marine pollution, marine safety research, customs and immigration laws, revenue loss and sanitary laws.
It may not use its powers in ways to impede innocent passage by imposing unduly burdensome or discriminatory requirements. The Convention provides that the laws do not apply to the design, construction, manning, and equipment of foreign ships in the state or giving effect to generally accepted international rules and standards, namely those agreed under the International Maritime Organization. The adjoining coastal state may suspend temporarily the rights of innocent passage in limited areas as long as it is non-discriminatory and essential for its security.
The right of arrest may be exercised in the above cases, even if the ship is exercising rights of innocent passage through territorial seas. If the ships cease to be engaged in innocent passage, then a more stringent measures may be applied in that context.
There is controversy as to the extent of the innocent passage regime. The general view is that it applies broadly so that plant and equipment such as oil rigs moving through territorial waters are covered. What is most controversial is whether warships are covered. There is no international consensus and the matter was not dealt with by the Law of the Sea Convention.
One view is that warships require prior notice to the adjoining state. Another view requires prior consent. The third view is that no authorisation or notification is required provided the warship complies with principles of innocent passage.
This latter view is highly contentious as the view can be taken that the mere presence of a warship in territorial waters is not per se innocent. On the other hand, some of the activities recognized as within the scope of innocent activities may be undertaken by warships. Submarines traveling at surface are expressly recognised.
The purpose of the right of innocent passage is to facilitate international traffic. In many cases there should be no need to traverse territorial waters. However, in the case of straits such as Gibraltar, it is necessary to traverse territorial waters. In this case, international law leans towards the right of free navigation. Warships will generally be allowed innocent passage through narrow straits used for international navigation.
The coastal state is not generally allowed to suspend the right of navigation for any class of vessel. In this case, straits are between one significant area of the high seas and another and are a recognised route of navigation. This is so even if another alternative convenient navigation may exist.
The principle has been extended from the high seas to the head of gulf when the territorial seas were increased from three to 12 nautical miles. Certain strategic bodies of water ceased to be part of high seas.
The Law of the Sea Convention provided for the right of transit passage through all straits connecting high seas or exclusive economic zones, which are used in international navigation which do not have a corridor of high sea or EEZ running through it or the strait is created by an island belonging to the adjoining state, seaward of which there is an alternative route.
The right of transit passage is wider than the right of innocent passage. It applies to military ships, submerged submarines and aircraft. They must proceed without delay and refrain from any threat or use of force against the adjoining states.
Ships and aircraft must comply with international requirements on safety matters. The coastal states may regulate maritime safety includes traffic, international rules on environmental protection, prevention of illegal fishing and loading and unloading activities in the context of revenue, immigration, and public health laws.
The customary status of transit passage has not been fully clarified. Some coastal states are not party to the Convention and a customary right may need to be relied on in this context.
The expanse of archipelagic baselined referred to above, is subject to the principle of archipelagic sea lane passage in corridors designated by the state. This is similar to the right of transit passage reducing the jurisdiction of the archipelagic state in the interests of international navigation.