Chinese maritime law in the South China Sea

Besides military might, China has used a variety of political, economic and legal tools to better control the South China Sea (also known as the East Sea). The recent change in the Chinese Maritime Traffic Safety Law (MTSL) is another step in its new “gray areawhich raises serious concerns among neighboring countries in the region. In general, the new law strengthens China’s control over vessels crossing China’s territorial sea. However, due to China’s current claims on the Paracel and Spratly Islands, the free passage of ships in international waters is also affected.

The international legal norm relating to innocent passage through territorial waters

Under the United Nations Convention on the Law of the Sea (UNCLOS), the sovereignty of a coastal state extends beyond its land territory and internal waters to an adjacent belt of sea, qualified of “territorial sea”. The territorial sea may extend to a maximum of 12 nautical miles from the baseline of the coastal State. For islands belonging to a State, the territorial sea regime also applies. Note that an island is defined as an area of ​​land that meets the following conditions: naturally formed, surrounded by water, and above water at high tide. The passage of a vessel passing through the territorial sea of ​​another State is deemed innocent as long as it does not affect the peace, good order or security of the coastal State. UNCLOS also provides a general list of criteria for defining innocent passage. In addition, UNCLOS also grants the coastal State the right to take the necessary means to prevent and slow down any passage that is not innocent. However, there are no specific guidelines on these means and the State can exercise its sovereignty by enacting and enforcing regulations on the matter.

China’s new MTSL legal requirement for innocent passage through territorial waters

– Increasing Chinese control in the South China Sea as prescribed by the new law

China’s earlier Territorial Sea and Contiguous Zone Law of 1992 provided that foreign military vessels needed permission to enter its territorial waters, submarines had to transit on the surface; and ships carrying toxic materials had to have the required documents and take precautions when handling cargo. The new MTSL makes several changes to these requirements, in which foreign operators of submersibles, nuclear ships, ships carrying radioactive materials, and ships carrying bulk petroleum, chemicals, liquefied gas, and other toxic substances and harmful should provide detailed information including vessel name, call sign, current position, cargo, port of call and estimated time of arrival when visiting Chinese territorial waters. The new MTSL grants China the power to establish ship routing and reporting zones, traffic control zones and restricted navigation zones. Vessels passing through important fishing waters, areas of heavy vessel traffic, ship routing areas and traffic control areas must increase their lookout, maintain safe speeds and comply with specific navigation rules. The new MTSL strengthens enforcement of the revised Chinese Coast Guard Law, passed in February 2021. It says foreign warships and other government vessels used for non-commercial purposes that violate Chinese laws and regulations during an innocent passage shall be dealt with with all necessary means in accordance with “relevant laws and administrative regulations”. In general, the new law does not directly oppose the provisions of UNCLOS. The new law establishes ambiguous definitions of the types of applicable vessels and the circumstances that may pose threats to China’s national security. Although this scope, according to a loose interpretation, could include any type of vessels that Chinese authorities deem “dangerous” at their own discretion, including fishing boats, as well as coast guard vessels from neighboring countries. However, it is risky for China to restrict the right of innocent passage exercised by foreign ships in its territorial sea. Onerous reporting and information submission requirements may cause difficulties or block the passage of such vessels. The enforcement and penalties imposed under the “relevant laws and administrative regulations” are also ambiguous and overbroad. This can be seen as another restriction of the right of innocent passage under UNCLOS.

– China’s illegal claim to the South China Sea

Since the applicable geographical area of ​​the new MTSL is China’s territorial sea, China’s unwarranted claim to this area is the main reason why the new law imposes many restrictions on innocent free passage through the South China Sea. . The MTSL applies to sea areas under Chinese jurisdiction. However, which areas are China’s territorial sea is unclear. If China abides by international law and exercises its power in the legitimate territorial sea within 12 nautical miles of its coastal baseline, the new MTSL would not raise so many concerns. However, China has illegally occupied several islets in the Paracel and Spratly Islands and turned them into military bases with regular troops stationed there. These facilities are also equipped with air defense systems, strategic runways and jetties for warships. By carrying out such actions, China has attempted to convert the artificial islets into landmass and treat them as islands. China has tried to found such artificial islands to establish territorial waters – a surrounding area of ​​12 nautical miles. This is a blatant attempt to circumvent UNCLOS regulations. First of all, UNCLOS only recognizes the territorial maritime zone established based on naturally formed waters, surrounded by water and being out of water at high tide. Meanwhile, apart from the illegal occupation, China has changed the status of many islets and recognizes these islets as the legitimate grounds for establishing their territorial sea area to impose passage restrictions, despite UNCLOS. Second, in the dispute brought by the Philippines against China in 2016, the special arbitral tribunal had already rejected China’s claims regarding the generation of maritime zones based on such artificial islands. China, however, does not recognize the decision and has continued its military expansion in the region.

– The gauge of the application of the new law

The United States Navy (“US”) 7th Fleet announced the entry of an American warship near Mischief Reef (called “Da Vanh Khan” in Vietnamese), which is part of the Spratly Islands and has been illegally claimed and occupied by China. On September 8, 2021, just a week after the new MTSL took effect, the US warship was operating and sailing near Mischief Reef, where the territorial sea area was claimed by China. The 7th Fleet also denied being chased by Chinese warships and aircraft. Although not a party to UNCLOS, the United States has declared that the natural state of Mischief Reef is not entitled to a territorial sea and therefore land reclamation efforts, facilities and structures built on this feature do not change its characterization under international law.


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