Maritime Law: How Far Does Its Reach Extend?

Maritime law, also known as admiralty law, applies to activities on the high seas or in areas of ocean beyond any one country's waters. It also applies to a country's territorial waters, which extend 12 nautical miles from the baseline of a coastal state. Within this zone, coastal states exercise full sovereignty, including the right to enforce laws on customs, immigration, and pollution control. Beyond the 12-mile limit, there is still a lot of ocean that falls under the exclusive economic zone (EEZ), which can extend up to 200 nautical miles from the coast. In these regions, vessels and aircraft from any country are free to pass through, but crimes are governed by the laws of the country that owns the vessel. This can create jurisdictional complexities, especially when vessels are on the move.

Territorial waters

The territorial sea is a belt of coastal waters extending at most 12 nautical miles (22 km) from the baseline of a coastal state. The territorial sea is sovereign territory, although foreign ships (military and civilian) are allowed innocent passage through it, or transit passage for straits. This sovereignty also extends to the airspace over and seabed below.

The contiguous zone is a band of water extending up to 24 nautical miles (44.4 km) from the baseline. Inside, a state can exercise limited control to prevent or punish "infringement of its customs, fiscal, immigration or sanitary laws and regulations within its territory or territorial sea". The zone is typically 12 nautical miles wide, but it can be wider or narrower depending on the state's claimed territorial sea.

The exclusive economic zone (EEZ) extends from the baseline to almost 200 nautical miles (370.4 km) and therefore includes the contiguous zone. A coastal nation has control of all economic resources inside its exclusive economic zone, including fishing, mining, oil exploration, and pollution of those resources. However, it cannot prohibit passage or loitering above, on, or under the surface of the sea that complies with the laws and regulations adopted by the coastal state.

The continental shelf refers to the seabed and subsoil of the submarine areas that extend beyond the territorial sea, up to 200 nautical miles or beyond, where the natural prolongation of a coastal state’s land territory exists.

Contiguous zone waters

Within the contiguous zone, a nation can exercise a degree of control to prevent and address violations of specific laws and regulations within its territory or territorial sea. This includes customs, fiscal matters, immigration, and sanitary regulations. For instance, the US Coast Guard is authorised to board any vessel within this zone under the suspicion of drug or weapons smuggling. However, the jurisdiction of a nation in the contiguous zone does not cover matters of navigation or overflight.

The width of the contiguous zone can vary depending on the extent of the territorial sea claimed by a nation. Typically, the contiguous zone is 12 nautical miles wide, but it can be wider if a nation claims a smaller territorial sea, and narrower if it overlaps with another nation's contiguous zone. In such cases of overlap, there is no standard rule, and nations must negotiate a compromise.

The contiguous zone is distinct from the exclusive economic zone (EEZ), which extends up to 200 nautical miles from the baseline. Within the EEZ, a nation has sovereign rights over economic resources and activities such as fishing, mining, and oil exploration.

The legal basis for the contiguous zone is provided by the United Nations Convention on the Law of the Sea (UNCLOS), which sets out the rights and responsibilities of nations in their maritime zones.

International waters

The starting point of international waters is generally recognised as 12 nautical miles (approximately 22.2 kilometres) from the coastal baseline of a nation. This principle is enshrined in the United Nations Convention on the Law of the Sea (UNCLOS), which states that coastal states have full sovereignty over their territorial waters, including the right to regulate and enforce laws on customs, immigration, and pollution control.

In international waters, the laws that govern are based on the country where the ship is registered and the flag it is flying. For example, if you are on board a cruise ship registered in the Bahamas, you are subject to Bahamian laws. However, when it comes to lawsuits from injuries sustained while on board a vessel, the laws that apply can depend on other factors and circumstances surrounding the incident. In some cases, a lawsuit may be filed in the country where the ship is registered, while in other cases, it may be permitted to file a lawsuit in a U.S. state or federal court.

While international waters provide some freedoms, certain activities are universally considered illegal, including piracy, drug trafficking, human trafficking, illegal fishing, unauthorised dumping of hazardous materials, and engaging in acts of violence or terrorism. International treaties and conventions, such as UNCLOS, provide a legal framework to address these offences.

It is important to note that crimes committed in international waters pose unique jurisdictional challenges. Generally, crimes committed aboard vessels fall under the jurisdiction of the flag state, which is the nation under whose laws the vessel is registered. However, many countries exercise universal jurisdiction for certain serious crimes, such as piracy and drug trafficking, allowing them to prosecute individuals regardless of their nationality or the vessel's flag.

Exclusive economic zones (EEZ)

Maritime law can vary depending on how far away from the coast a vessel is. The seas and oceans are divided into distinct maritime zones, each with its own legal framework.

The Exclusive Economic Zone (EEZ) is a zone adjacent to a coastal state's territorial sea, extending up to 200 nautical miles (370 kilometres) from the baseline (the low-water line along the coast). The EEZ is governed by the United Nations Convention on the Law of the Sea (UNCLOS).

Within the EEZ, coastal states have sovereign rights and jurisdiction over natural resources, both living (such as fish) and non-living (such as oil, gas, and minerals). They also have the responsibility to conserve and manage these resources. Coastal states can regulate the use of resources and impose penalties on those who do not abide by their regulations.

Vessels of other states have the freedom of navigation within the EEZ, as well as the more restricted right to “innocent passage” through the territorial sea. However, the coastal state has greater authority over foreign vessels in the territorial sea.

There are three main types of EEZ boundaries:

• Treaty boundaries: Formally recognised by neighbouring countries and therefore not contested.
• Median line boundaries: Used when boundaries are not defined by a treaty or agreement between two or more coastal states. These connect points equidistant from the coastlines of both states.
• Disputed boundaries: Some EEZ boundaries are disputed, leading to large areas of disputed EEZ.

The practice of claiming an EEZ has given rise to customary international law. For example, the United States is not a party to UNCLOS but claims an EEZ that extends 200 nautical miles from its baseline.

Navigable waters

In the United States, the basis for federal jurisdiction over navigable waters is derived from the Commerce Clause (Article 1, Section 8) of the Constitution. This was established in the 1824 Gibbons v. Ogden case, where the Supreme Court ruled that the navigation of vessels in and out of the nation's ports is a form of interstate commerce, and therefore, federal law takes precedence over state law.

The Rivers and Harbors Appropriation Act of 1899 forbids the building of any unauthorized obstruction to the nation's navigable waters, and grants enforcement powers to the U.S. Army Corps of Engineers.

Internationally, a nation is accorded sovereignty over the waters extending 12 miles from its coastal baseline, according to the United Nations Convention on the Law of the Sea (UNCLOS). This distance is known as territorial waters. For a total of 24 miles from the coastal baseline, a nation may enforce a contiguous zone where it can implement certain customs, laws, and regulations. Beyond 24 miles, a vessel is considered to be in international waters, where the laws of the country in which the ship is registered and the flag it is flying apply.

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