The effectiveness of the US’ counterintelligence capabilities has been brought into question in recent weeks, after it emerged during a pre-trial hearing ^[1] on 8 April that a US Navy flight officer had been charged with espionage ^[2] over allegations that he passed secret information to Taiwan and possibly China. One of the most troubling aspects of the charge is that the officer may have compromised key US maritime surveillance assets and activities in the South China Sea.

According to a heavily redacted Navy charge sheet ^[3], Lieutenant Commander Edward Lin, a US citizen born in Taiwan, is accused of two counts of espionage, three counts of attempted espionage, three counts of making false official statements and five counts of communicating defence information ‘to a person not entitled to receive said information’. New information released last week ^[4] revealed the evidence against Lin was at least partially the result of a government sting involving an FBI informant, whom it met with on five occasions ^[5]. He has been held in pre-trial confinement in Virginia for the past eight months, after he was arrested attempting to board a plane from Hawaii to mainland China.

Taiwan, a key strategic ally to the US, has denied any involvement ^[6] in the matter, which the FBI and Naval Criminal Investigative Service are jointly pursuing ^[7] as a ‘national security case’. The incident, like many others made public by Snowden, reinforces the age old intelligence adage ‘there is no such thing as a friendly intelligence service, just an intelligence service of a friendly nation’.

Given Lin’s military career and knowledge of sensitive US intelligence collection methods, US authorities have plenty of reasons to be worried. Lin served ^[8] on the staff of an assistant secretary of the Navy for financial management and comptroller, where he likely had access to highly classified strategic weapons planning, before being assigned in 2014 ^[9] to the Special Projects Patrol Squadron at Marine Corps Air Station Kaneohe Bay as a flight officer. Lin’s experience within the patrol squadron is a serious security concern for the US. As part of the squadron, Lin had experience ^[10] managing the collection of electronic signals from the EP-3E Aries II signals intelligence aircraft, whose missions include anti-surface warfare, anti-submarine warfare mining, reconnaissance and surveillance.

The Aries has undergone significant upgrades ^[11] in recent years and now delivers ‘near real-time’ signals intelligence and full motion video, allowing the Navy to pinpoint threats and eavesdrop on foreign militaries. Additionally, Lin may have had access to the P-8A Poseidon surveillance aircraft ^[12]. In the current military environment, any intelligence concerning how the US conducts signal operations could be highly valuable to foreign governments, presenting them with the opportunity to counter US surveillance.

The implications of this case are far-reaching, most significantly in the South China Sea where tensions between the US and China continue to intensify ^[13] over the US’ military surveillance operations. Currently, both the P-8A and the EP-3E play pivotal roles in tracking China’s naval activities in the region, and as such, determining each plane’s exact capabilities and vulnerabilities is of vital importance to Beijing.

The US has been increasing its surveillance flights over the region in previous months. In December 2015 it deployed the P-8A to Singapore ^[14] for the first time, in a move China described as ‘regional militarisation by the ^[15] US ^[15]‘. Prior to Singapore, the US had deployed the P-8A to the Philippines on a number of rotations—including for three weeks in February 2015 ^[16]—in order to conduct surveillance flights over the South China Sea.   

Given the ever-growing tensions in the South China Sea, access to secret intelligence has increased in value. This access provides a strategic advantage, reducing the uncertainty surrounding the actions of other countries, and offering an insight into their intentions. The latest alleged breach could have provided China with an understanding of US intelligence collection capacity, and based on the planes’ capabilities, possibly provided them with enough information to deceive US intelligence collection in the future.

In addition, there is a concern ^[17] that Lin may have provided intelligence regarding how and at what range the US Navy can detect a Chinese attack submarine. The knock-on effect of this is that the PLA may now be armed with the information to allow them to avoid America’s submarine hunters.

The use of secret intelligence in the South China Sea is not limited to the US. Australia—which also conducts military surveillance ^[18] in the region—will also have to come to terms with the strategic implications of this breach, and realise it may not be immune from attempts similar to these in the future.

While this isn’t the first time China has been in the position to access information on the capabilities of the US Navy ^[19], Lin’s arrest adds to increasing US concerns regarding Chinese espionage ^[20] and the effectiveness of counterintelligence programs.

Given the high stakes in the South China Sea in the coming months, the Lin case is sure to grasp the attention of the US military and the general public as proceedings continue. As US authorities struggle to establish the extent to which their maritime surveillance capabilities and intelligence collection requirements have been compromised, this latest alleged incident of espionage may have implications for the US for many years to come. The next question becomes how the US will prevent it from happening again.