By Patricia Lam, Senior Associate, Pace International Law Review
The U.S.-China underwater drone incident reveals legal grey areas in the international law of the sea.
On December 15, 2016, a Chinese warship seized an underwater drone belonging to the United States in the Philippine exclusive economic zone (EEZ), about 50 miles North West of Subic Bay. The underwater drone was taken from the USNS Bowditch, which the Pentagon declared was an unarmed oceanographic survey ship. The Pentagon said that the drone was navigating lawfully while collecting data about the salinity, temperature, and clarity of the water. If this were true, then the U.S. drone should not have been seized. China on the other hand, claimed that seizure of the unidentified vehicle was a lawful attempt to prevent navigational safety issues. Despite the contradicting claims, one thing is clear- there are troubling legal grey areas with regard to the Convention on the Law of the Sea.
This treaty, known as United Nations Convention on the Law of the Sea (UNCLOS), calls for technology transfers and wealth transfers from developed to undeveloped nations. It also requires parties to the treaty to adopt regulations and laws to control pollution of the marine environment. More importantly, it aims to allow certain ships to traverse the high seas without interference. However, this recent incident on international waters highlighted some ambiguities in the treaty.
If the drone can be classified as a vessel or warship, then it would be afforded sovereign immunity, which would implicate China’s seizure to be a disruption of the freedom of navigation. This would make China’s seizure of the drone a violation of UNCLOS. According to UNCLOS Article 32, the sovereign immunity of the device would be unaffected by the treaty if it was a warship or other government ship operated for non-commercial purposes. Article 29 however, defines a warship as, “a ship belonging to the armed forces of a State bearing the external marks distinguishing such ships of its nationality, under the command of an officer duly commissioned by the government of the State and whose name appears in the appropriate service list or its equivalent, and manned by a crew which is under regular armed forces discipline.” Since the drone was not manned by a crew, it cannot be defined as a warship. Whether the drone can be defined as a vessel or a ship is left in a grey area because UNCLOS does not define either word.
The other challenge to the sovereign immunity and freedom of navigation argument in Articles 58 and 87 is that the activities conducted must be with “due regard” for the rights of other states in the EEZ and high seas, as well as the safe conduct and operation of other ships and aircraft. This is another grey area because it is not addressed in UNCLOS whether underwater drones present a potential navigational hazard to the extent that the U.S. may have failed to exercise “due regard” for the rights of the Philippines. This was what China attempted to argue- that they were protecting the area from a navigational hazard when it “scooped” up the drone before realizing it belonged to the U.S.
Did the U.S. violate UNCLOS?
It is stipulated that the drone did not navigate with a flag identifying its nationality, nor did the Philippines issue permission to the U.S. to conduct their survey in its EEZ. This is vital information because Article 40 states that marine scientific research can only be undertaken in a country’s EEZ with its permission. However, since the U.S. is not a signatory to the treaty, it technically did not violate UNCLOS. This brings about another legal concern- whether UNCLOS applies to non-ratifying states like the U.S. by way of customary international law.
 Steven Jiang & Kevin Bohn, China returns seized US underwater drone, CNN: Politics (Dec. 20, 2016, 9:00 AM), http://www.cnn.com/2016/12/20/politics/china-drone-return/
 Ben Blanchard & Steve Holland, China to return seized U.S. drone, says Washington ‘hyping up’ incident, Reuters (Dec. 18, 2016, 11:18 AM), http://www.reuters.com/article/us-usa-china-drone-idUSKBN14526J
 David A. Ridenour, Ratification of the Law of the Sea Treaty: A Not-So-Innocent Passage, National Policy Analysis (Aug. 2006), http://www.nationalcenter.org/NPA542LawoftheSeaTreaty.html
 Mark J. Valencia, US-China Underwater Drone Incident: Legal Grey Areas, The Diplomat (Jan. 11, 2017), http://thediplomat.com/2017/01/us-china-underwater-drone-incident-legal-grey-areas/
 United Nations Convention on the Law of the Sea, 1833 UNTS 3 /  ATS 31 / 21 ILM 1261 (1982), http://www.un.org/depts/los/convention_agreements/texts/unclos/unclos_e.pdf
 Mark Valencia, U.S.-China drone spat: more than meets the eye, The Japan Times: Opinion (Dec 29, 2016), http://www.japantimes.co.jp/opinion/2016/12/29/commentary/world-commentary/u-s-china-drone-spat-meets-eye/#.WIfkhPLmqUk