On December 15, 2016, China seized an American unmanned underwater vehicle (UUV) in the South China Sea.Footnote 1 The drone had been launched by an American naval vessel, the USNS Bowditch. According to press reports, “[t]he American crew was in the process of retrieving the device when a small boat dispatched from the Chinese vessel took it as the American sailors looked on.”Footnote 2 China has made extensive—and contested—maritime and territorial claims in the South China Sea, including within an area delimited by the “nine-dash line.”Footnote 3 The incident occurred outside of this area,Footnote 4 and none of the Chinese government's statements related to the seizure suggest any assertion of Chinese jurisdiction over the waters where the drone was seized.Footnote 5 After an exchange of diplomatic statements, China returned the drone to the U.S. Navy.
Neither the United States nor China specified the precise status of the waters in which the drone was seized under the law of the sea. The location, approximately fifty nautical miles from a major port in the Philippines’ Subic Bay, appears to be within the Philippines’ Exclusive Economic Zone (EEZ).Footnote 6 Pursuant to the UN Convention on the Law of the Sea (UNCLOS), states have certain rights of navigation within another state's EEZ, including freedom of scientific research.Footnote 7 The Pentagon has maintained that the drone was being used to carry out scientific research, but both American and Chinese experts recognized that the drone could have been used to gather intelligence on Chinese submarine activity.Footnote 8 China declined to comment on this question.Footnote 9
Regardless of the UUV's purpose, analysts have argued that China had no legal basis to seize the UUV because UNCLOS and customary international law relating to sovereign immunity preclude such seizures.Footnote 10
Immediately after the drone was seized, the Pentagon called on China to return the drone:
Using appropriate government-to-government channels, the Department of Defense has called upon China to immediately return an unmanned underwater vehicle (UUV) that China unlawfully seized on Dec. 15 in the South China Sea while it was being recovered by a U.S. Navy oceanographic survey ship. The USNS Bowditch (T-AGS 62) and the UUV—an unclassified “ocean glider” system used around the world to gather military oceanographic data such as salinity, water temperature, and sound speed—were conducting routine operations in accordance with international law about 50 nautical miles northwest of Subic Bay, Philippines, when a Chinese Navy PRC DALANG III-Class ship (ASR-510) launched a small boat and retrieved the UUV. Bowditch made contact with the PRC Navy ship via bridge-to-bridge radio to request the return of the UUV. The radio contact was acknowledged by the PRC Navy ship, but the request was ignored. The UUV is a sovereign immune vessel of the United States. We call upon China to return our UUV immediately, and to comply with all of its obligations under international law.Footnote 11
The next day, before the issue was resolved, then-President-elect Trump suggested he would take a different approach, tweeting: “China steals United States Navy research drone in international waters—rips it out of water and takes it to China in unprecedented act.”Footnote 12 He followed up: “We should tell China that we don't want the drone they stole back.- let them keep it!”Footnote 13
On December 18, 2016, the Chinese Defense Ministry issued a statement announcing its intention to return the drone:
Chinese Defense Ministry spokesperson Yang Yujun said late Saturday that China has decided to hand over the U.S. underwater drone it captured in its waters to the United States in an appropriate manner. According [to] Yang's statement on the website of the defense ministry, on the afternoon of December 15, a Chinese naval lifeboat located an unidentified device in the waters of the South China Sea. In order to prevent the device from causing harm to the safety of navigation and personnel of passing vessels, the Chinese naval lifeboat verified and examined the device in a professional and responsible manner. Upon examination, Yang said, the device was identified as an underwater drone of the United States. The Chinese side has decided to hand over it to the U.S. in an appropriate manner. Both sides have been maintaining communication on the issue, Yang noted. The U.S. side's unilateral move to dramatize the issue in the process is inappropriate, and not conductive to its settlement. “We regret that,” Yang added. It is worth emphasizing that for a long time, the U.S. military has frequently dispatched vessels and aircraft to carry out close-in reconnaissance and military surveys within Chinese waters, Yang said. “China resolutely opposes these activities, and demands that the U.S. side should stop such activities. China will continue to be vigilant against the relevant activities on the U.S. side, and will take necessary measures in response,” said the spokesperson.Footnote 14
The next day, the State Department confirmed that military-to-military discussions had resulted in an agreement for the return of the UUV, while maintaining that China's seizure of the craft had been in violation of international law:
The device that we're talking about is—it's a scientific research device. It's meant to help us with oceanographic studies. … I don't know what specifically they had tasked this UUV to do on that particular day, but it was doing oceanographic work and only oceanographic work. … [The UUV] absolutely was operating inside international waters, and it was absolutely performing necessary scientific research, certainly within the bounds of international law. And the absconding with it acted against that very international law, which is, again, why we're going to get it back … . Ambassador Baucus, our ambassador in Beijing, personally was involved in the discussions which led to our ability now to get it returned … . So yes, we were absolutely engaged right there at our ambassador's level.Footnote 15
That same day, Foreign Ministry Spokesperson Hua Chunying fielded questions about the return of the UUV, stating that the decision had been made “via the military-to-military channel.”Footnote 16 She deflected questions about then-President-elect Trump's comments:
There have been abundant comments from various parties on remarks made by US President-elect Trump on Twitter. I will not add to them. … An unidentified device was discovered by a lifeboat of the Chinese Navy in waters of the South China Sea. In order to prevent this device from posing danger to the safe navigation of passing ships and personnel, the Chinese side checked and verified the device in a professional and responsible attitude. After identifying the device as a UUV from the US, the Chinese side decided to hand it over to the US side in an appropriate manner. It is learnt that the two sides are in smooth communication through the military-to-military channel, which will definitely lead to a proper settlement of this issue.Footnote 17
On December 20, 2016, a Chinese ship returned the UUV to the United States Navy off the shores of the Philippines near where it was taken.Footnote 18 The Pentagon was clear in calling the seizure “unlawful”:
Today, the People's Liberation Army-Navy vessel 510 returned a U.S. Navy Ocean Glider Unmanned Underwater Vehicle (UUV) to the United States, near the location where it had been unlawfully seized on Dec. 15. USS Mustin (DDG 89) received the vehicle for the U.S. in international waters approximately 50 nautical miles northwest of Subic Bay. The seized UUV is a sovereign immune vessel of the U.S. Navy which was conducting routine operations in the international waters of the South China Sea in full compliance with international law. It had just completed a pre-programmed military oceanographic survey route and was returning to the nearby USNS Bowditch (T-AGS 62). Ocean Gliders such as this are used regularly by the U.S. Navy and other militaries throughout the world.
This incident was inconsistent with both international law and standards of professionalism for conduct between navies at sea. The U.S. has addressed those facts with the Chinese through the appropriate diplomatic and military channels, and [has] called on Chinese authorities to comply with their obligations under international law and to refrain from further efforts to impede lawful U.S. activities. The U.S. will continue to investigate the events surrounding this incident and address any additional findings with the Chinese, as part of our ongoing diplomatic dialogues and the Military Maritime Consultative Agreement Mechanism.
The U.S. remains committed to upholding the accepted principles and norms of international law and freedom of navigation and overflight and will continue to fly, sail, and operate in the South China Sea wherever international law allows, in the same way that we operate everywhere else around the world.Footnote 19
The State Department addressed China's comment that the UUV posed a threat to the safety of navigation:
First of all, [the UUV] was identified. It's—I think it says U.S. Navy right on the side of it. I can check, but I'm pretty sure it does. But there's no dispute about who it belonged to, and while it might not be manned, it was being operated remotely by U.S. Naval personnel and research scientists on the Bowditch, the ship that—from which it was operating.
So look, … while this might be an interesting discussion to have, it's kind of a waste of your time and mine, okay? The UUV belonged to the United States Navy, it was operating in international waters in accordance with international law, it was doing research—valuable scientific research—there was no threat to navigation, it was never just off on its own. I mean, it wasn't like they weren't monitoring what it was doing, right? It … didn't decide to just go rogue and … become a problem for navigation. So this is an academic exercise that's going to be fruitless for both you and me. It belongs to the United States and we're glad we have it back, it should never have been taken in the first place, end of story.Footnote 20
