A "New Departure"? The legal bases of UK drone strikes in Syria

Meeting to mark the first anniversary of the publication of the Birmingham Policy Commission on ‘The Security Impact of Drones’, discussion at the  All Party Parliamentary Group on Drones was dominated by the UK’s controversial Reaper strike against two UK nationals in Syria this summer. Cameron’s decision to justify this action on grounds of self-defence of the UK was recognised as making a distinct break from previous UK rules of engagement. The Policy Commission identified a distinctive British approach to the military use of drones, which contrasted with the US government’s “cross-border counterterrorist campaigns”. In tacit recognition of this, Cameron described the decision to strike inside Syria as a ‘new departure’. Whether the strike was the departure, however, or the justification for that action, remains hotly debated.

Indeed, the justification offered by Cameron to Parliament appears tenuous unless the UK government is now operating with a very different concept of imminence to that which it has previously employed. Traditional international law recognises a right of self-defence under both treaty and customary law. In this case, there was no prior armed attack against the UK that could trigger this right. Customary international law does recognise the legality of a pre-emptive use of force but it is widely accepted by international lawyers that such a right of anticipatory self-defence only exists when the ‘necessity of that self-defense is instant, overwhelming, and leaving no choice of means, and no moment of deliberation’.

The only legal justification that could be invoked relies on the US reinterpretation of the meaning of imminence that has underpinned its policy of targeted killing outside of recognized international armed conflicts. On this argument, there was, in Cameron’s words, ‘a clear and present danger’ and consequently, a firm legal basis to kill individuals, even if there is no specific evidence of an imminent attack. The Prime Minister made specific reference to threats posed in relation to the VE celebrations, but since the strikes took place after these events had passed off without incident, and no related domestic arrests occurred, it supports the contention that the UK has adopted the US definition of imminence.

Of equal concern is the subsequent obfuscation of the justifications advanced for the RAF Reaper strike. Here, a second legal argument was articulated in a letter the UK’s Permanent Representative to the UN sent to the Security Council. This argued that the armed insurgency against the Iraqi government from Islamic State forces provides justification for UK military forces to engage in a collective self-defence of Iraq. This explanation, however, co-exists uneasily alongside the initial explanation, with the letter repeating the claim that those targeted ‘were engaged in planning and directing imminent armed attacks against the United Kingdom’. The collective self-defence argument certainly places the government on safer ground, though it is quite different from the anticipatory self-defence rationale that Cameron invoked on 7 September.

The significance of the government using its drones for the first time for targeted killing outside of recognized battlefields is not just the novelty of the action, but also the decision to justify this in terms of a new legal doctrine of imminence. As the UK government prepares in the forthcoming Strategic Defence and Security Review the need to set the principles to regulate the use of lethal force from the air has never been more urgent. The Birmingham Policy Commission charted a clear path here, and we would argue that the restrictive approach to collective self-defence conforms with established legal principles, and the government’s stated commitment to a rules based international order.  Attempts to deviate from those principles, however politically expedient, need to be resisted lest they set regrettable precedent.

Professor David Hastings Dunn, Head of the Department of Political Science and International Studies, University of Birmingham.

Professor Nicholas Wheeler, Director of the Institute for Conflict, Cooperation and Security, University of Birmingham