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Experience April/May 2024

The Murky Law of Espionage

Seth D Kramer


  • What are the current protocols, norms, or laws related to peacetime espionage?
  • Spying can advance national security and international security. But where it advances personal or corporate interests or internationally wrongful acts, it may be illegal.
  • Enforcement is always a challenge for international lawyers.
The Murky Law of Espionage
Vadym Plysiuk via Getty Images

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In a 10-year span, Asaf Lubin went from working for a spy agency to “suing the spooks,” as he describes it. “I like to claim that has given me a centrist position through which to see the world, which is often lacking.”

Lubin’s current mission? Advocating for clearer laws governing espionage.

The associate professor at Indiana University Maurer School of Law was an intelligence analyst for Israel before attending law school. After law school, he spent a year as a fellow with Privacy International, a London-based nonprofit devoted to the right to privacy and curtailing governmental and corporate surveillance. He’s the author of a forthcoming book, The International Law of Intelligence: the World of Spycraft and the Law of Nations, from Oxford University Press.

Recently, I spoke with Lubin to find out more about today’s laws when it comes to espionage.

SK: What are the current protocols, norms, or laws related to peacetime espionage?

AL: In the old world, there was an absolutist way of thinking about spying. Spying was either always legal, always illegal, or neither legal nor illegal, a.k.a., extralegal.

For permissivists, spying was always legal. Chinese military strategist Sun Tzu said, “Spy, spy, and spy again.” English philosopher Thomas Hobbes believed spying was like “rays of light onto the human spirit.” He reasoned that a leader who chooses not to spy commits a dereliction of duty; they’re not protecting the polity from surprise attacks in a world where there’s growing uncertainty around safety and security. So any spying, no matter what the means or targets are, is always lawful.

A second approach was a prohibitionist approach—spying is always illegal. Philosopher Immanuel Kant promoted a perpetual peace and believed the way to achieve it was by building trust among nations. The thing that hurts that trust, he believed, were the lies, cheating, and deceiving that come with espionage.

Kant thus called spying a diabolical act. So for Kant and those who took Kantian positions, the idea is that spying, no matter the reason, the means, or the targets, will always be illegal.

The third camp are those who’ve claimed that espionage and international law just start from opposite positions. International law is about the peaceful resolution of conflict. Spying is about lying, cheating, and deceiving. International law is about justice where justice was once trampled. Espionage is about circumvention of justice.

Spying is also filled with dualities that make it hard to regulate. We tell our spies to violate the laws of other countries but to comply with ours. We treat spies as heroes at home but traitors abroad.

All these dualities seem to suggest that there’s just something queer about this practice. It’s nonbinary. Everyone’s doing it, but everyone’s saying it’s illegal under their own domestic legislation. So extralegalist scholars suggest that spying is neither legal nor illegal; it’s outside the bounds of law.

Those are the three camps. But I think the majority of international lawyers are no longer there. Today, there’s a relativist way of thinking. Spying is sometimes legal and sometimes illegal. The only question is where we draw the lines of illegality.

Most relativist scholars are generalists. They say that espionage isn’t regulated per se because there’s no treaty or customary rule that applies to peacetime espionage. Therefore, we can regulate particular acts of spying only by searching for general principles of law that control those practices.

For example, if a country spies from an embassy or inside an embassy, that country violates international law because it violates the 1961 Vienna Convention on Diplomatic Relations, which prohibits both spying on an embassy and from an embassy. Similarly, if you spy from within the territory of a state without its consent, you’re violating that state’s sovereignty and other general principles of international law relating to territorial integrity or political independence.

In other words, we look to general law to address particular espionage episodes. So if the U.S. finds a Chinese spy balloon traversing over missile bases in Montana, the regulation for it won’t come from some special rules on espionage. Instead, generalists will turn to the Convention on International Civil Aviation of 1944, known as the Chicago Convention, to determine the legality of this practice.

SK: What are your views on the laws of espionage?

AL: The perspective I have, which is a minority view held by some international lawyers and intelligence studies scholars, is that there are, in fact, customary rules of international law on espionage derived from the practice of intelligence agencies and the reactions of the international community to those practices.

These rules take into account the rich history—which goes back to the dawn of humanity—around the way intelligence is collected, analyzed, verified, and promulgated. It’s just a different way of thinking about espionage regulation whereby we can apply nuanced, tailored, specific intelligence rules and not force ourselves to identify some general obligations from treaties and frameworks that weren’t created to address this particular problem.

SK: How would your perspective apply to the situation regarding the balloon from China?

AL: Take the decision of the U.S. to shoot down that balloon. If I’m applying the Chicago Convention, as the generalists require, there are obvious restrictions against downing it. The U.S. is prohibited from resorting to the use of weapons against a civilian aircraft that poses no immediate threat.

So if the balloon was a civilian weather research aircraft, targeting it would be prohibited. Similarly, if the balloon was a military spy aircraft, as the U.S. contended, shooting it down would equally be prohibited because it’s entitled to sovereign immunity.

But such a formalist and sterile analysis seems to be detached from reality. It avoids, for example, the need to ask more complex questions about what the Chinese were doing in Montana in the first place. So instead we might ask the more concrete questions of: What was the intention of the operation? What were the methods employed in this spying? Were they necessary, proportionate, efficacious? By looking at a special legal regime—a lex specialis of intelligence law—we might identify unique and particularized remedies.

For example, pursuant to the Vienna Convention, if an ambassador is found spying, the country that caught him can’t arrest him. It can’t bring him to criminal justice because the convention protects the diplomat’s immunity from the criminal jurisdiction of the receiving state.

The only response available to the receiving state is to declare that ambassador a persona non grata and let him go back to his home country. This kind of special remedial framework—as set out within the Vienna Convention—is what I suggest we do for all espionage activities. So even if it’s true that under general law it would be illegal for the U.S. to target the balloon in response to the alleged espionage, doing so might nonetheless be legal under a specialized regime that prioritizes a different set of remedial solutions.

Similarly for China, it might be OK—depending on the circumstances—to send this kind of spy balloon into American airspace in the first place. Think of the U2 spy planes of the 1960s. The U.S. used these vessels to spy on the Soviet Union’s nuclear and missile sites.

Why was it justified for the U.S. to do so but not China? And what about the Soviets’ decision to shoot down a plane and detain its pilot, Francis Gary Powers? If we just apply general law, we’re not able to consider this history as a guidepost for thinking about contemporary acts of espionage.

All my framework asks is that we embrace these historical examples as precedent that sets the scene for determining legality or illegality.

SK: Does your treatment of peacetime espionage take into account that peacetime spying can keep the world safer? For example, when China spies on the U.S., it obtains information. And in the nuclear age, information from espionage can prevent mass annihilation.

AL: Absolutely. Because we’re able to think about espionage under a specialized regime, we’re also able to take into account the very functions of intelligence in our public world order. Doing so entails that we recognize that intelligence can be both stabilizing and destabilizing. It can enhance international security or decrease it.

Recognizing this duality entails that we draw the lines of permissibility not around general principles like sovereignty in complete disassociation with the function that intelligence served in a particular context. Rather we should look to understand what the motivations were to determine the permissibility of a specific operation.

So where spying advances national security or international security, it may be legal. But where it advances personal or corporate interests or internationally wrongful acts, it may be illegal.

SK: Would your analysis also consider the permissibility of particular methods and tactics used in espionage?

AL: Yes, there can be situations where the espionage campaign would be lawful, but particular choices around means and methods might not be. For example, in the leadup to catching Osama bin Laden, the CIA ran a sham hepatitis B vaccination program for children in Abbottabad, Pakistan. The idea was that somehow through the collection of DNA and blood samples, they’d be able to spot where bin Laden and his family were hiding.

The operation always had very little chance of success. Indeed, it didn’t succeed in finding bin Laden. Yet the operation caused a huge amount of collateral damage. When Pakistani families learned of the incident, they refused to vaccinate their children, with the Taliban even issuing a fatwa against vaccination programs and teams.

To this day, local leaders in the region mischaracterize polio vaccination as a Western spying program. Imposing such a grave risk with such limited likelihood of success or high likelihood of harm should be prohibited.

My framework suggests that there will be particular methods that should be illegal because of the way the intelligence operation is employed. Again, I’m not looking at general international law to prove the illegality. Rather, I’m looking at the specifics of what the espionage operation was intended to do, how it was done, what rules of engagement were set up, and what was ultimately achieved to establish what the prohibitions should be.

SK: In your framework regarding espionage in peacetime, is there any sort of enforcement mechanism other than each country wanting to save face with the rest of the world?

AL: Enforcement is always a challenge for international lawyers. The problem with the traditional generalist approach is that there’s a mismatch between what countries do and what generalists claim the law to be.

Right now, we say it’s illegal to spy in the territory of another state without its consent, but everyone does that. Right now, we say it’s illegal to spy from embassies, but every country spies from embassies. And so on.

There’s a mismatch between how the law is presented and reality. I think this is highly problematic for the legitimacy of the law. If the prescriptive rule doesn’t match what we’re seeing in the world, there’s a real concern. People start doubting if the rule is even a rule since it’s never enforced.

My framework, on the other hand, recognizes that espionage is a secret and historical practice with rich and complex modes of enforcement. The way I think about enforcement isn’t purely from a positivist, formalist, court-order-based model.

There are a lot of ways by which countries can signal to other countries that a line has been crossed. It doesn’t always require formal sanction-based methods of legal enforcement. Rather, we might engage various forms of diplomatic signaling through back channels. Or we might engage in all sorts of countermeasures.

Think about the options below-the-armed-attack-threshold cyber operations might entail. There’s a reason some have argued that cyber competition is an extension of the intelligence competition. We might turn to cyber operations as a pressure valve for achieving the same aims that formal enforcement once achieved—deterrence, incapacitation, retribution, restitution, and so on.

Spy swaps are another example of surveillance diplomacy and nonformal modes of enforcement. The U.S. and the Russians (and the Soviets before them) have engaged for years in spy swaps. What are these swaps? They represent a complete departure from the criminal process. After all, the spy is convicted and sentenced, and yet their prison sentence is sweetened to advance broader political and diplomatic goals—in bringing back our spies.

At the moment of the spy swap, both countries acknowledge that the captured individuals were in fact spies or, at least, that they care about them so much that they’re willing to trade convicted and sentenced spies for them. That does suggest that the two countries, in that moment—which is such a bizarre moment—are willing to let the secrecy go away for a brief sense of clarity where we implicitly admit that spying happened.

Not only that, but we tolerate what you did enough to return your spies back to you if you’ll tolerate what we did enough to return our spies back to us instead of imprisoning or executing them. Spy swaps are thus a mode of espionage enforcement. But they require us to embrace a nonformal way of thinking about enforcement to see it.