I was just reading this post over at Lawfare debating whether the use of targeted killing is justified on analagous grounds to the use of deadly force by the police in resolving a hostage situation. Heller, in arguing that it is not, suggests that law enforcement is justified in using lethal force without trial only when the threat is particularly imminent. While disagreeing with Heller’s conclusion Wittes (the author of the post) seems to agree that imminence is the key issue.

Certainly as far as US constitutional jurisprudence goes this isn’t the rule. In TENNESSEE v. GARNER, 471 U.S. 1 (1985) the court held

It is not, however, unconstitutional on its face. Where the officer has probable cause to believe that the suspect poses a threat of serious physical harm, either to the officer or to others, it is not constitutionally unreasonable to prevent escape by using deadly force.

Notice the lack of any mention of imminence. Of course both common sense (and perhaps even other precedents) suggest that if other non-lethal means could be used to eliminate the threat then it would be unjustified to use lethal force. However, apriori consideration shows that reasonable outcomes require that it it be the absence of reasonable non-lethal means to avert a likely harm, not the imminence of the harm, that must justify lethal force against a dangerous individual.

The easiest counterexample is that of a terrorist on the verge of dispersing a surely lethal biological agent with a several week incubation period. Even though the deaths wouldn’t occur for several weeks surely it is justifiable to use deadly force to stop the terrorist from dispersing the germs. Thus it can’t be the imminance of the fatalities that matter but maybe it’s the imminance of the harm where the harm is injection with the biological agent. But surely it would make no difference if instead the terrorist was about trigger a remote device in an unknown, undiscoverable location in a major city that would disperse the biological agent after a week long countdown.

So maybe then it’s the imminance of the murderous act that is relevant regardless of when the consequences come to pass. Thus deadly force is justified in the above examples because the subject is on the verge of an action that seriously threatens the lives of others. This is an attractive view but again we can show this can’t be the right rule by considering a hypothetical.

This time imagine the terrorist has stolen a deadly biological weapon from a military lab but the spores are contained in a tamper resistant box that will take about 5 minutes to be opened. The terrorist is making no attempt to open the box but is about to steal a tank which the police know he plans to drive into a nearby city where he will release the biological agent. Surely if the police know that once inside the protection of the tank they will be powerless to stop the terrorist lethal force is justified in preventing him from entering the tank. I could extend the example further but the point seems clear, the law must deem lethal force justifiable when it’s the last and only chance to prevent a highly probable future murder even if that murder is distant in time and space from the use of the force. Our normal intuitions about the need for an imminent threat are a consequence of the fact that in most situations where the harm is not imminent the use of lethal force can be delayed without great risk.

Still one might distinguish the tank stealing terrorist case from the targeted killing situation by appeal to the fact that the tank stealing terrorist is currently in the midst of a concrete attempt to take lives. However, we allow law enforcement to kill hostage takers who are merely threatening to kill others but not currently executing a lethal plan and surely having a leadership position in a genuine terrorist organization puts you in the position of threatening to kill others, after all that’s your publicly stated goal. Moreover, in such a situation it is impossible to know when the terrorist leader might order an attack so one rarely will have reason to believe the killing may be delayed without incurring substantially more risk. Indeed, the situation seems very similar to a hostage taker, who may or may not be wearing a real bomb, visible through the window to the police sniper where the mere chance that the hostage taker might set in motion a deadly chain of events is enough to justify lethal force.

This suggests to me that the relevant distinction with respect to targeted killings is between those killings undertaken for the purposes of direct self-defense, i.e., to stop a terrorist leader from ordering/organizing a deadly attack, and those undertaken for strategic reasons, e.g., killing a terrorist leader with a purely PR role to instill fear in potential allies of the group. I’m not sure when either should be allowed but this seems to be a much more reasonable place to draw a line than imminence.

On a different point I suspect that it would actually be extremely easy for a suspect terrorist to remove themselves from the US government’s list of targets. Far from being flung in a dark hole in the ground if such an individual presented themselves at a US consulate I’m sure the CIA would offer them piles of cash to reveal information about their contacts.