For soldiers to be compliant with the laws that apply during armed conflict, they must have independent moral agency, to be capable of understanding and acting on reason.
In 2002 Canadian troops were conducting a night-time training exercise on a live firing range at Tarnak Farms, outside Kandahar in Afghanistan. Overhead, the pilots of two US F-16 fighter aircraft mistook the live gunfire for an attack by Taliban insurgents and dropped a bomb, killing four Canadian soldiers and wounding a further eight. At the time, the pilots were returning to their home base in Kuwait following a 10-hour long-range patrol mission, and interpreted the live fire as a threat to their aircraft, engaging under self-defence. However, two subsequent boards of inquiry found that the pilots had failed to follow appropriate flight procedures. In the debate that followed the incident, discussions focused on the pilots’ defence – that their judgment had been impaired as a result of using amphetamines to combat fatigue, the drugs having been issued to them by the US Air Force.
Although the precise role of amphetamines in the Tarnak Farms incident is unlikely to ever be fully understood, it raises some key concerns regarding the effects of drugs on individual responsibility in conflict. For soldiers to be compliant with the laws that apply during armed conflict, they must have independent moral agency, to be capable of understanding and acting on reason. This requirement underpins the legal basis for their conduct in war. Any inability for soldiers to make rational choices – or to act freely on these choices – could render them not legally responsible for their actions under international criminal law.
It is plausible that pharmacological interventions could interfere with the ability of soldiers to form the mens rea.
The key issue of responsibility and drug use in conflict concerns two possible effects; 1) the influence of drugs on soldiers’ mental capacity, and 2) their influence on soldiers’ ability to control their behaviour. On the point of mental capacity, it is plausible that pharmacological interventions could interfere with the ability of soldiers to form the mens rea (literally, ‘guilty mind’) necessary to be held accountable for their actions in war. Mens rea refers to the mental state of criminal intent that is required for criminal responsibility: its absence when committing an offence precludes the attribution of criminal responsibility to the perpetrator. The distinction of mens rea varies according to jurisdiction, but Article 30 of the Rome Statute of the International Criminal Court (ICC) determines that this mental element comprises two components; intent and knowledge. An individual has intent where they mean to engage in the conduct, and mean to cause, or were aware of, the consequences, while knowledge concerns the awareness that a circumstance exists or the consequence will occur. For the pharmacologically enhanced soldier, any drug that were to considerably affect mental capacity – to the extent that it interfered with their awareness and ability to appreciate the consequences of their actions – could therefore render them no longer legally responsible. An example of this can be seen in the Rome Statute exemption for intoxication, whereby defendants are excluded from criminal responsibility if they were to be ‘in a state of intoxication’ (as long as the intoxication was involuntary). Therefore, where a soldier no longer has the mental capacity to determine the rational consequences of their actions, they would not be able to uphold their moral obligations under international humanitarian law.
Similarly, if a pharmacological intervention were to destroy a soldier’s capacity to control their behaviour, they would equally be excluded from criminal responsibility. Although beyond the scope of this research paper, the possibility of soldiers no longer controlling their own individual behaviour is a particularly important consideration in the development of some alternative military enhancement technologies, such as neurostimulation, or exoskeletons, where enhancement could remove control of a soldier’s actions to a third party – whether intentionally or unintentionally (for example if such technology were to be hacked by an adversary).
The issue of moral responsibility is significant because the state has a responsibility for the conduct of its state ‘organs’, including those organizations and individuals acting on its behalf, such as the armed forces and service personnel. Therefore, were an enhanced soldier to commit a wrongful act, and were such an enhancement to be the product of a state intervention, i.e. to form part of an armed forces enhancement programme, this could constitute a breach of a state’s international obligation. Such a failure would challenge the legal responsibility of the state, and therefore dispute its legitimacy to engage in warfare. If a state could not account for the responsible actions of its military, its justification to use armed force would be ethically and legally undermined. Therefore, any pharmacological performance-enhancing technology introduced to the military must not degrade a soldier’s mental capacity or ability to act according to his/her own free will.
