Leading military lawyer says refinements of technology already used on stealth bombers could breach international laws

This article is more than 4 years old

This article is more than 4 years old

“Invisibility cloaks” and other future advances in military camouflage techniques could violate the Geneva conventions, a top military lawyer has warned.

Refinements of technologies that are already used on stealth bombers could breach compliance with international laws regulating armed conflict if equipment is disguised or soldiers’ weapons are hidden, according to Bill Boothby, a former air commodore and deputy director of RAF legal services.

Scientists and military contractors are spending tens of millions of pounds researching methods for generating effective invisibility through more sophisticated “metamaterials” – substances designed to absorb or bend light and/or radar waves in order to conceal approaching aircraft or troops.

The US Defense Advanced Research Projects Agency (Darpa) has been one of the major funders of metamaterial science, triggering excitable comparisons with Harry Potter’s fictional invisibility cloak. Last year the US army announced it was planning to test prototype metamaterial uniforms.



Such chameleon-style technology is not entirely new. The first stealth planes went into service with the US air force in the 1980s and took part in air raids on Kosovo, Afghanistan and Iraq. Their narrow profile, radar-absorbing paint and deflectors are intended to make them virtually invisible to enemy radar.



In Weapons and the Law of Armed Conflict, a comprehensive survey of emerging defence technologies published this month by Oxford University Press, Boothby highlights difficulties further technological success could pose.

“Patented ‘Adaptiv’ technology [developed by BAE Systems in Sweden] uses cameras on-board the target, such as an armoured vehicle, to pick up infra-red readings of the background scenery,” he notes.



“The same background pattern heat signature is then projected onto a series of hexagonal ‘pixels’ mounted on the target that can change temperature very rapidly to match the surroundings.



“As a result, an object can be made to disappear into the background for an observer using an infrared sensor; it can also be used to mimic the infrared reading of a different vehicle, so a tank looks like a civilian car, for example.”



Under article 37 of the 1949 Geneva conventions, ruses such as camouflage, decoys, mock operations and misinformation are all permitted.



“Conventional camouflage,” Boothby suggests, “aimed, for example, at causing the enemy to blend into the background, is lawful and bending light might be regarded simply as a technologically sophisticated way of achieving that outcome.”



But if camouflage is used to pretend to be a non-combatant in order to deceive the enemy and thereby to cause death, Boothby says, it could be outlawed under the Geneva convention clause entitled “prohibition of perfidy”.



Similarly, camouflage that involves misuse of enemy, UN, protective, or neutral signs, flags and emblems is banned. Wearing an invisibility uniform might, it is suggested, additionally breach a combatant’s obligation to have a fixed distinctive sign recognisable at a distance and to carry arms openly.



“A combatant whose weapon is rendered invisible by its coating is arguably not complying with the minimal requirements [of carrying a weapon openly],” he states.

Boothby used to run the government unit responsible for ensuring that newly acquired weapons conform to the UK’s international humanitarian law obligations.

He also points out that the ban on incapacitating chemical agents under the Chemical Weapons Convention is preventing development of non-lethal gases that could be used safely in anti-terrorist hostage operations such as the 2002 Moscow theatre siege.

“A number of states are undertaking research in this field, either with a view to employing the technology or to developing countermeasures,” he said.

“The stated position of the UK government is that the development, production, retention, acquisition, or use of incapacitating chemical agents for military purposes is prohibited.”

On development of autonomous weapons systems capable of identifying and attacking targets without human intervention, beyond the capability of the present generation of drones, Boothby takes the view that these “killer robots” are “unlikely to raise international weapons law concerns”.

Human Rights Watch and others have called for a ban on the autonomous weapons systems but Boothby believes as long as there is a human capable of supervising targeting decisions made by machines and overriding them if they fail to distinguish between civilian and military targets they should remain legal.

Such systems should only be permitted if the human supervisor’s workload is low enough to “ensure that proper decisions are made”, he notes. That qualification means swarms of small drones – a potential future use of remotely piloted aircraft – may pose legal problems since they could be too numerous to be monitored adequately.

“An outright ban of autonomy in weapon systems is premature and inappropriate, difficult to enforce and perhaps easy to circumvent,” Boothby says. “Existing law should be applied to this as to any other technology in warfare.”

Boothby’s book also considers the implications of military advances in the use of nanotechnology, lasers, expanding bullets, “human enhancement technologies” and outer space weapons.

“Outer space is of critical importance for numerous vital functions in the modern world,” he points out. “In the military context, these include [guidance for] anti-ballistic missile operations, long-range precision strike and ground-based mid-course missile defence missions, intelligence, and communications activities. It therefore seems likely that outer space will become a focus for future conflict.”

There is virtually no treaty law regulating conflict in space apart from the 1967 outer space treaty, which states that all uses of outer space must be “in accordance with international law” - implying any warfare should be conducted as it is on Earth.



“Hostilities in outer space seem likely to involve the direct attack of space assets such as satellites using kinetic or cyber weapons, electronic attack in the form of jamming or spoofing, laser blinding, and electromagnetic pulse attack,” Boothby comments.

“Customary law prohibition of weapons that are indiscriminate by nature may have relevance to outer space weapons.”

Weapons designed to create a cloud of debris that continued circling the planet might therefore be deemed illegal on the ground of being indiscriminate.

• This article was amended on 15 March 2016 because an earlier version said B2 stealth bombers went into service with the US air force in the late 1980s. This has been corrected to say the first stealth planes went into service with the US air force in the 1980s. B2 stealth bombers went into service in the 1990s.