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Rewarding Compliance

On Normative Implications of Rewarding in International Law


In their recent article, Rewarding in International Law, Anne van Aaken and Betül Simsek provide a novel typology of incentives that exist to promote compliance with international law, arguing that positive incentives – rewards – are both more prevalent and more useful than the existing literature on compliance leads one to think. Drawing on behavioural insights from psychology, political science and international relations, the authors suggest that rewards are in many ways likely to be more effective than negative incentives – sanctions – in pushing States towards law-compliant behaviour.

My purpose in this post is to build on Van Aaken and Simsek’s article by posing – and sketching brief responses to – three questions. First, does rewarding undermine legal normativity? Secondly, what does it mean for our understanding of compliance? And, thirdly, what would its increased use mean for the international order?

Rewarding Bad Behaviour?

Van Aaken and Simsek distinguish internal rewards (the benefits accruing to a State from membership to a treaty) from external rewards (benefits “on top” of the treaty), both of which can be given upon entry to the treaty or once the State is a treaty party in order to ensure compliance. My focus in this post is on compliance-related rewards and, in particular, on external rewards.

Van Aaken and Simsek recognise that there are some treaties for which the internal rewards – the ‘bargain struck’ in the agreement – isn’t enough in itself to motivate compliance. And they argue that if those treaties provide global public goods (like multilateral environmental agreements) or have third-party beneficiaries (like human rights treaties), this deficit should be made up with external rewarding (p. 206), such as economic or military aid (p. 216).

The authors approach this from an avowedly rationalist perspective, which provides us with theoretical clarity and the ability to generate testable hypotheses. But the idea that States should be (or perhaps need to be) rewarded to comply with their international obligations feels wrong. Shouldn’t States just comply with the legal obligation? Otherwise, what’s the point of having a legal rule in the first place? Van Aaken and Simsek’s article raises some interesting questions about rewards and how they may change (or perhaps dilute) legal normativity. Put simply, the question is this: Does giving rewards for what States should be doing anyway undermine law’s normativity, its ‘ought’ power?

Outside of rational choice theories of international law, the idea that legal norms have some kind of special effect on behaviour is widely acknowledged. They have a unique quality – a ‘compliance pull’ (here, at p. 26) – that can only be explained by reference to a grundnorm, a rule of recognitionthe rule’s perceived legitimacy, or by the fulfilment of certain conventional criteria; a quality that differentiates legal rules from other social norms. Actors abide by the law even if it isn’t in their self-interest (at least partially) precisely because it is the law. So, would rewarding States to comply with existing treaty obligations undermine this?

I think there’s a danger that it might. Take, for example, the idea that law takes effect by providing a practical reason for action: the law “addresses norms to agents and expects them to guide their actions by those norms … it expects those norms to figure in deliberation, nor as contextual features setting the environment or parameters of choice, but as reasons for deliberative choice.” (here, at p. 370). In order to do this effectively, these norms need to be clear and they need to have been enacted by the appropriate means. But importantly, they also need to be capable of providing the reason for the desired behaviour; they cannot rely on auxiliary incentives to motivate that behaviour.

By saying that a reward is necessary to motivate compliant behaviour, the implication is that the underlying norm can no longer exert the ‘compliance pull’ that is characteristic of legal rules. (If that is indeed the case, then one wonders whether the subject-matter was appropriate for legal regulation.) In such a case, legal normativity is so weak it can’t be undermined. But if law does assert some compliance pull and rewards are seen as a tool to move treaty parties from, say, partial to full compliance, there would seem to be a danger that a State’s reason for complying with the rule shifts from a sense of legal obligation to simply wanting to benefit from a reward. Put simply, it would threaten to make law less law-like.

Reconceptualising Compliance

Van Aaken and Simsek understand compliance to be “the interaction between rules and behaviour”, where the former has a causal impact on the latter (footnote 3). This is a relatively uncontroversial definition of compliance but one that slightly differs from other definitions, which tend to focus on the conformity of actors’ behaviour to a legal norm rather than the causal relationship between the two (here, at p. 117; and here, at p. 478). (Indeed, perhaps this is because causation is, unlike conformity, rather difficult to show.) Despite this, I think that Van Aaken and Simsek’s definition is one that would be recognised and endorsed by many international lawyers: compliance is only compliance if the law has caused (at least partially) that behaviour.

But this definition of causation leads to a problem. Are we really talking about compliance, understood thus, if States need to be given external rewards to adopt compliant behaviour? I think not, because the necessary causal link is missing. Put another way, but for the reward, the State’s behaviour would not be in conformity with the legal norm; the law does not cause the desired behaviour. We’re not rewarding compliance, but rather just inducing a kind of pseudo-compliance where the induced behaviour mirrors that of compliant behaviour.

Does it matter that such reward-motivated behaviour falls outside of our definition of compliance? Perhaps not if we’re just focussed on promoting behaviour that is desirable, such as that which protects global public goods or individuals’ rights. Here, law is just a means to an end. But as international lawyers, I think we’re interested in more than that: we’re interested in working out how rules can be designed to promote desirable behaviour, how institutions can be created to facilitate this behaviour, and how positive incentives can be leveraged to increase law’s impact on the relevant actors in practice. The concept of compliance is useful to us because it tells us something about the bounds of the power of law.

I don’t have a straightforward answer here. All I can say is that Van Aaken and Simsek’s definition of compliance is common sense, but raises questions about how external rewards fit in with compliance-related behaviour. The very notion of compliance is acknowledged, rightly, in the literature to be a slippery concept. But expanding our views of incentivising compliance, as Van Aaken and Simsek convincingly argue for, also gives us cause to revisit this foundational concept.

Capacity to Reward

This leads me to my final point. Van Aaken and Simsek argue that for (the prospect of) a reward to be effective in changing State behaviour, it “should be clearly within the rewarder’s capability to fulfil and should not be beyond budget capacity” (p. 239). To be sure, rewards are diverse in their forms: the reward could be redemption within an international organisation after outcasting, it could be in the form of praise, or it could be ‘in kind’ rewards, such as acceptance into the European Union. But, as Van Aaken and Simsek recognise, a ‘classic’ form of external reward is payment, whether that be economic aid, military aid, or otherwise (p. 216). And, clearly, only the richest countries have the (credible) capacity to provide such rewards.

To be sure, this mirrors the effectiveness of negative incentives, such as economic sanctions, which also depend on the sanctioner’s credible threat of enforcement. In this respect, negative incentives are certainly no better than positive incentives. However, if we want to consider rewards as a potentially effective additional mechanism for changing State behaviour, we need also to have our eyes open to the power imbalances that such incentivising facilitates. International law has never been neutral, but do we want to accentuate these asymmetries?


Van Aaken and Simsek’s article breaks new ground on thinking about how to incentivise State behaviour. It shows persuasively that positive incentives have, from a behavioural perspective, the upper hand when compared to negative incentives. In this post, I’ve tried to build on their solid theoretical basis to identify some of the normative issues that may arise from the use of rewards. Van Aaken and Simsek’s article opens our eyes to how international institutions could operate, but we need to think carefully about the implications of rewarding.

Daniel Peat

Daniel is an Assistant Professor of Public International Law at the Grotius Centre for International Legal Studies at Leiden Law School. He is currently conducting research on compliance with international investment awards, which is funded by the Leiden University Fund/Dr. H.A. van Beuningen Fonds.

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