Nations around the world are responding to terrorism with a combination of law enforcement measures and military action. In the United States, for example, the federal government has prosecuted terrorists responsible for the 1993 World Trade Center bombing, the 1998 assaults on U.S. embassies in Kenya and Tanzania, and the attacks of September 11, 2001. At the same time, the government also has been using its armed forces against al Qaeda terrorists in Afghanistan, Iraq, Sudan, Yemen, and other places. Other countries also are fighting terrorism with both criminal proceedings and military force, including Egypt, Israel, Russia, Turkey, and the United Kingdom.
When governments respond to terrorism using military force, a debate often arises about the legality of the steps taken. As this Article will show with numerous examples, the debate has familiar contours. Opponents of military counterterrorism measures typically argue that they violate legal guarantees designed to protect criminal suspects. They assert, for instance, that domestic and international laws do not permit the government simply to shoot suspected terrorists or to detain them indefinitely or to try them outside of ordinary courts. But governments and their supporters have a standard reply to this objection. They assert that they are not merely addressing crime, but instead are fighting a war against terrorism, and that the law applicable to armed conflict allows them to employ the military measures that they have used. In the United States, the familiar refrain is: we took these kinds of actions in World War II when we were fighting the Nazis and the Japanese, and therefore we can take them in the war that we are fighting against al Qaeda.
So at present, debates about the legality of governmental responses to terrorism often boil down to disagreements about which law governs. Is it the law that regulates law enforcement actions? Or is it the law of armed conflict? The choice matters. Those who believe that the rules that apply to law enforcement actions must govern military responses to terrorism consider many of the responses that governments actually have taken to be illegal. And those who believe that the law of armed conflict applies tend to think that they fall wholly within accepted standards of war fighting.
Take the issue of targeted killing. A country engages in targeted killing when it locates and summarily kills a suspected terrorist. The United States has engaged in this practice in its struggle against terrorism. For example, in the summer of 2006, the Air Force killed Abu Musab al-Zarqawi, the leader of al Qaeda in Iraq, by locating his safe house and then dropping bombs on his house. A few years earlier, the Central Intelligence Agency (“CIA”) fired missiles at suspected members of al Qaeda in Yemen, without trying to bring them into custody. Israel also has done targeted killing, attacking Palestinians in the West Bank, Syria, and other places. And Russia reportedly once sent a poisonous letter to kill a Chechen leader.
Is the targeted killing of suspected terrorists lawful? As explained more fully below, everyone agrees that ordinary law enforcement rules in the United States (and in most other places) do not generally permit the police simply to kill criminal suspects. Instead, they must attempt to arrest them. The police can use deadly force only to prevent a suspect from escaping, and even then only if the suspect poses a threat of serious physical harm to others and, if feasible, the police previously have given the suspect a warning. In contrast, long-established principles of the law of war say that military forces generally may target and kill enemy forces in the course of a lawful armed conflict wherever they find them, and without giving them a chance to surrender, unless the enemy forces already have laid down their weapons and given themselves up.
But what do these two sets of rules say about the targeted killing of suspected terrorists? At present, the answer appears to depend on which of the two sets of rules apply. Opponents of targeted killing might view suspected terrorists as criminal suspects, concluding that the government cannot simply target and kill them. Meanwhile, proponents of targeted killing by military forces might consider the suspected terrorists to have the status of enemy combatants in an armed conflict. If the two sides disagree on the proper characterization of the suspected terrorists and of the governmental action taken against them, they will reach conflicting views about which set of legal rules should apply. In turn, they will arrive at different conclusions about the legality of any targeted killing.
In this Article, I make three claims concerning this issue. In Part II, I claim that characterizing counterterrorism measures as either law enforcement efforts or military actions for the purpose of determining their legality is now, and long has been, a central feature of counterterrorism law. Disputes over characterization have arisen in no fewer than eight different subject areas, ranging from targeted killing to the responsibility of the government to provide compensation to persons inadvertently injured by the governmental action. Disagreements about characterization have arisen not only in the United States but also in many foreign countries. And these disputes are not new; they have occurred for many decades.
In Part III, I claim that determining the legality of governmental responses to terrorism by attempting to characterize counterterrorism measures as either law enforcement or military action is not a good system. Terrorists, and counterterrorism efforts, generally defy simple characterization into one category or another because terrorists resemble enemy combatants in some ways and criminal suspects in others. In addition, the different subject areas in which the issue of characterization arises vary from each other in so many respects that a characterization that makes sense in one area does not necessarily make sense in another. In fact, as the Article will show, the United States has found it difficult to take a consistent view on characterization, despite the centrality of the question.
In Part IV, I claim that the law would be improved by moving to a system that judges counterterrorism measures as counterterrorism measures without trying to characterize them as either law enforcement actions or military actions. In other words, the United States and other nations ought to develop new standards to regulate governmental responses to terrorism rather than debating whether the laws of war or the rules of law enforcement should apply. Already imperfect examples of this alternative approach are emerging. They include both the Israeli Supreme Court’s 2006 decision on targeted killing and, to some extent, the thinking behind the Military Commissions Act of 2006.