After Fragmentation. Norm Collisions, Interface Conflicts, and Conflict Management

Abstract

Fragmentation, institutional overlaps, and norm collisions are often seen as fundamental problems for the global (legal) order. Supposedly, they incite conflict and disorder. However, some scholars have also emphasized functional and normative advantages of the resulting institutional pluralism. We argue that the consequences of the increasing international institutional density are conditional on whether and how different norms, institutions, and authorities are coordinated. In distinction from the fragmentation framework in international law and the regime complexity framework in international relations, this introduction outlines an interface conflict framework that enables important insights into this question and guides the contributions assembled in this issue. It zooms in on the micro-level of conflict between actors that justify incompatible positional differences with reference to different international norms. In particular, the concept of interface conflicts allows studying the conditions under which overlaps and norm collisions become activated in conflicts as well as the ways in which such conflicts are handled. Foreshadowing the main findings of the contributions to this Special Issue, we hold that interface conflicts are neither inevitable nor unmanageable. Most importantly, it seems that, more often than not, conflicts stimulate cooperative forms of management and contribute to the building of inter-institutional order.

Full text

Global Constitutionalism (2020), 9:2, 241–267 ©Cambridge University Press, 2020. This is an Open Access
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doi:10.1017/S2045381719000315
After fragmentation: Norm collisions, interface
conflicts, and conflict management
christian kreuder-sonnen
Friedrich Schiller University Jena, Carl-Zeiss-Str. 3, 07743 Jena, Germany
Email: christian.kreuder-sonnen@uni-jena.de
michael zu
¨rn
WZB Berlin Social Science Center, Reichpietschufer 50, 10785 Berlin, Germany
Email: michael.zuern@wzb.eu
Abstract: Fragmentation, institutional overlaps, and norm collisions are often seen
as fundamental problems for the global (legal) order. Supposedly, they incite conflict
and disorder. However, some scholars have also emphasised functional and norma-
tive advantages of the resulting institutional pluralism. We argue that the conse-
quences of the increasing international institutional density are conditional on
whether and how different norms, institutions, and authorities are coordinated. In
distinction from the fragmentation framework in international law and the regime
complexity framework in international relations, this introduction outlines an inter-
face conflict framework that enables important insights into this question and guides
the contributions assembled in this issue. It zooms in on the micro-level of conflict
between actors that justify incompatible positional differences with reference to
different international norms. In particular, the concept of interface conflicts allows
studying the conditions under which overlaps and norm collisions become activated
in conflicts as well as the ways in which such conflicts are handled. Foreshadowing the
main findings of the contributions to this Special Issue, we hold that interface conflicts
are neither inevitable nor unmanageable. Most importantly, it seems that, more often
than not, conflicts stimulate cooperative forms of management and contribute to the
building of inter-institutional order.
Keywords: fragmentation; coordination; global order; institutional den-
sity; international institutions; regime complexity
I. Introduction
In the first decade of the twenty-first century, the number of international
organisations (IOs) (Drezner 2013: 284) and transnational institutions
(Tallberg et al. 2013), the amount of international authority (Zürn et al.
241
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2015; Hooghe et al. 2017), and the count of international treaties and
agreements (Pauwelyn et al. 2014; Hathaway and Shapiro 2017) have
reached all-time highs. The rise of transnational and international norms
and rules has caused two challenges for global governance. Externally, the
growing relevance of international and transnational institutions has given
rise to social forces that defend national sovereignty against intrusions by
cosmopolitan elites holding power in these institutions. Internally, it has
created an increasing institutional density in the international system
(e.g. Raustiala 2013: 296),
1
by which both collisions between norms or
rules at the international level (horizontally) and between international and
national ones (vertically) become more likely. This Special Issue focuses on
the internal challenge to global governance.
While approaching questions relating to institutional density and norm
collisions from two different –normative vs. descriptive –angles, scholar-
ship in both international law and international relations (IR) tends to be
pessimistic about their effects (see Faude and Gehring 2017 for an over-
view). On the one hand, the focus of international lawyers has mainly been
on the fragmentation of international law that arguably undermines the
unity of the international legal system. It is seen as an antipode to the
constitutionalisation of international law that promises legal certainty and
thus allows for the development of an international rule of law (Benvenisti
and Downs 2007; Dunoff and Trachtman 2009; Klabbers et al. 2009). On
the other hand, studies in IR have mostly revolved around the notion of
regime complexity and highlighted the possibilities for states to engage in
cross-institutional strategising in this context (Alter and Meunier 2009). The
prevailing assessment is that overlapping institutions are a source of conflict
(e.g. Margulis 2013) and that states’increased ability to resort to forum
shopping or regime shifting to further their goals undermines the law-based
international order (Drezner 2013; Gómez-Mera 2016).
However, scholars of both disciplines have also pointed out that the
process of constitutionalisation is inherently contested, implying that contes-
tation across legal spheres ‘doesnot (necessarily) descend into conflict but can
productively produce new institutions atthe domestic and global level’(Lang
and Wiener 2017:4;seealsoTehanet al. 2017). In our view, the conse-
quences of the growing institutional density for global order are thus far from
established (see also Peters 2017; Meggido 2019). As we argue in this Special
Issue, the question of how the existence of multiple, non-hierarchically
ordered sites of political and judicial authority affects the constitutional
1
The degree of institutional density can be inferred from ‘the number of operative organi-
sations (population) as well as the size of the space occupied by the institutions (area)’(Clarke
2019: 699).
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quality
2
of the global order depends on a) whether and when overlaps or
norm collisions lead to actual conflicts between actors, and b) whether and
how such conflicts are managed. It is the (lacking) coordination between
different norms, rules, and authorities that poses a problem, not the number
of norm collisions or institutional overlaps. The constitutionality of gover-
nance systems needs to be addressed by looking at the quality of conflict
management between different norms and authorities, not by assessing the
degree of institutional differentiation (Zürn and Faude 2013).
To study these questions, the Special Issue introduces an interface conflict
framework as a research programme that puts the focus on the micro-level of
conflicts between actors who refer to different international norms. We
introduce our perspective in distinction from the fragmentation framework,
which primarily works on the macro-level and is order-oriented, and the
regime complexity framework, which works on the meso-level and is
problem-solving oriented. With the shift to the micro-level of conflict, we,
first of all, reorient the focus from norm incompatibility identified by
observers to conflicts identified by actors –states, non-governmental orga-
nisations (NGOs), IOs, etc. –who justify their position with reference to
different international norms. We thus differentiate between an externalist
and an internalist approach. In legal as well as political science scholarship,
there is a preponderance of the externalist approach by which the relation-
ship of norms and rules is determined from the outside, that is, based on the
researcher’s analysis of the compatibility of the norms and rules in question.
By contrast, we seek to foreground an internalist approach that looks at the
perceptions and behaviour of actors involved in the respective governance
fields to trace the activation of norm collisions and analyse positional
differences between actors on the relationship of norms and rules. Our core
unit of analysis is what we term interface conflicts: incompatible positional
differences between actors about the prevalence of different international
norms or rules. We want to understand when, why, and how overlaps and
norm collisions are seen, used, and abused by the actors of world politics.
Secondly, the interface conflict framework directs attention to the
management of interface conflicts (see also Zelli 2011; Peters 2017). The
type and outcome of conflict management are decisive to determine the
consequences of institutional density. On the one hand, if conflict manage-
ment is outright refused by the actors or if positional differences play out in
2
To be sure, we do not assume that the global order currently is or ever has been constitu-
tionalised. Instead, we assume that every political order can exhibit greater or lesser constitutional
qualities. A fragmented order based on arbitrary rule is of lower constitutional quality, for
instance, than an integrated order based on the rule of law. The order’s constitutional quality
thus is an empirical question and we inquire how it is affected by the activation and management
of interface conflicts.
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the absence or disregard of procedural rules and thus lead to purely
power-based outcomes, the expectation of fragmentation is vindicated; on
the other, if conflict management follows procedural rules and produces
secondary norms to avoid or handle interface conflicts in the future, it
contributes to the creation of a coordinated inter-institutional order.
Depending on the normative underpinnings of this order, its global consti-
tutionalist aspirations can be more or less pronounced.
This micro-level perspective adopted in the contributions to this Special
Issue enables some important insights and findings. Most importantly,
institutional overlaps and norm-collisions do not necessarily lead to frag-
mentation of or chaos in the international order. This is so for two main
reasons. First, not all institutional overlaps or norm collisions get trans-
formed into interface conflicts. Many institutional overlaps and colliding
norms can co-exist more or less silently without stirring conflict among
actors. Their activation in interface conflicts most often is politically moti-
vated and not an inevitable side effect of institutional density (see, in
particular, Gholiagha et al., this issue). In some cases, we even see active
attempts to prevent interface conflicts through pre-emptive coordination
(Faude and Fuß, this issue).
The second reason points to the importance of conflict management. Even
where interface conflicts are activated, they do not necessarily have desta-
bilising effects on international law and order. Instead, some form of
cooperative conflict management either mitigates negative effects or even
generates new norms that at times come close to secondary norms
(Birkenkötter, this issue; Krisch et al., this issue). Of the cases analysed in
this Special Issue, none stands for a fully non-cooperative orientation in the
management of interface conflicts. While the contributions show a broad
variety of often decentralised and ad hoc forms of conflict management, the
terms of settlement are regularly norm- and order-generative rather than
undermining. This finding may cause some optimism from a global consti-
tutionalist perspective. However, the contributions also highlight that the
normative substance of the nascent inter-institutional order remains highly
contested and is in no way predetermined to reflect liberal values (see Moe
and Geis, this issue; Flonk et al., this issue). Moreover, the normative quality
of conflict management varies significantly and depends to some extent on
the type of conflict.
In section II of this introductory contribution, we outline the analytical
perspectives of fragmentation and regime complexity, and point to some
limitations and blind spots in the accounts adopting those frameworks. In
section III, we present our interface conflict framework. It introduces our
core unit of analysis, namely interface conflicts, as those conflicts in which
actors bring to bear norms or rules against each other and spells out the
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implications of an internalist approach to the identification of interface
conflicts. Furthermore, it describes our understanding of global governance
as a system of loosely coupled spheres of authority, which allows for the
distinction of interface conflicts that are rooted in one and the same or two
different spheres of authority. On that basis, we describe a research pro-
gramme centred on the conditions for and the shape of governance efforts to
pre-empt or manage those conflicts. In each of the subsections, we discuss
some of the findings by the contributors. In section IV, we then provide a
road map and present the contributions to this Special Issue.
II. Existing frameworks: Fragmentation and regime complexity
International law scholars have predominantly analysed norm collisions
through the lens of fragmentation that focuses on the macro-level of the
international legal system, whereas political science contributions have
adopted the conceptual perspective of regime complexity to look at meso-
level phenomena of sectoral institutions. We briefly outline both approaches
in turn and then point to some overarching problems and blind spots that an
interface conflict framework operating at the micro-level is apt to address.
The fragmentation framework
The notion of fragmentation of international law refers to both the process
and the result of the expansion and diversification of international law in a
non-hierarchically integrated manner (Martineau 2016). The post-Cold
War proliferation of international institutions –in particular, the rise of
numerous (quasi-)judicial dispute settlement bodies responsible for deter-
mining norms of international law within their specialised subfields –led to
the perception of jurisdictional overlaps and tensions between divergent
interpretations of general international law (Charney 1998). Given the
absence of a central global legislator or a single global court of appeal, there
is no mechanism for the hierarchical coordination of diverse international
legal regimes. In the light of emergent inter-jurisdictional struggles, fears
were expressed that this could undermine the coherence of the international
legal system. Against this background, the International Law Commission
(ILC) initiated a study group on the fragmentation of international law,
headed by Martti Koskenniemi (ILC 2006).
The debate about fragmentation among international lawyers is focused on
the macro-level of the international legal order as a whole. In particular,
scholarly contributions aim to assess the consequences of fragmentation for
the functioning and normative structure of international law and, on that
basis, formulate ideas for how to encounter the phenomenon. More often
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than not, these ideas take the form of structural visions where fragmentation
is considered as a given challenge that requires a response on the level of the
international legal system. There are three different camps with three different
responses: constitutionalists, constitutional pluralists, and legal pluralists.
Especially for global constitutionalists, the fragmentation of international
law is inherently problematic. The potential of conflicts and incompatibil-
ities between separate legal obligations is seen to undercut the normative
integrity of the international legal system. Specifically, it risks losses of legal
certainty as an element of the international rule of law by reducing ‘the
predictability and reliability of law application’(Peters 2017: 679; see also
Crawford and Nevill 2012). As Peters (2017: 680) puts it, ‘at the bottom of
the fragmentation debate lies a concern for a loss of legitimacy in interna-
tional law, a loss which will ultimately threaten the law’s very existence’. The
global constitutionalist response to this predicament is to aspire to a hier-
archically structured legal system with an institutionalised final authority
imposing a set of superior substantive norms (Dunoff and Trachtman 2009;
Fassbender 2009; Habermas 2008). The assumption is that constitutiona-
lising international law could thus reinstate legal coherence and certainty. By
contrast, constitutional pluralists highlight certain benefits of decentralised
governance systems, especially their capacity for flexible adaptation, the
possibility of contestation, and the introduction of checks and balances
(Krisch 2010:78–89; see also Kumm 2009). Global legal pluralists even
go a step further and see the fragmentation of international law as inherently
desirable as it creates both a source of innovation and ‘a site of discourse
among multiple community affiliations’(Berman 2007: 321). It then works
in the form of heterarchical interactions between different function systems
(Fischer-Lescano and Teubner 2004).
Another strand in the fragmentation literature is less concerned with
developing normative theories to (re-)construct the global legal order.
Instead, it deals with the more concrete question of how to immediately
deal with overlaps and potential conflicts between international norms
(Pauwelyn 2003) or international authorities (Shany 2003). Here, conflicts
are conceived as legal inconsistencies or overlapping claims to jurisdiction
that can and need to be resolved by way of legal techniques (ILC 2006).
Contributions to this debate thus mostly search for the best legal solutions to
collisions within and between branches of international law, such as rules of
lex specialis or lex posteriori and approaches rooted in private international
law (e.g. Broude and Shany 2011; Michaels and Pauwelyn 2011). While the
normative prescriptions are at times formulated with respect to specific legal
regimes such as the ‘trade-and-…’ nexuses and thus operate on a more
sectoral meso-level, the proposed solutions are still very often generally
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applicable formulas devised with a view to the frictionless functioning of the
international legal order as a whole.
The fragmentation framework has much strength and inspired a research
programme that provided multiple new insights into the evolution and nor-
mative structure of the international legal system characterised by overlapping
and partially competing claims to authority. In particular, its macro-perspective
on problems at the level of the global political system has highlighted the
possibility of collisions between regimes that stand for fundamentally different
goals such as free trade and environmental protection (see Young 2011;Blome
et al. 2016). We embrace this notion of the global governance system as
consisting of different normative spheres that stand in an interdependent yet
non-hierarchical relationship with each other (Zürn 2018).
The regime complexity framework
In parallel to the fragmentation debate in international law, the growing
institutional proliferation and density at the international level also led IR
scholars to go beyond their previous focus on single and separate interna-
tional institutions to analyse interactions between institutions with over-
lapping regulatory functions.
3
In this context, Raustiala and Victor (2004)
coined the term ‘regime complex’to denote a set of non-hierarchical insti-
tutions with partially overlapping jurisdictions that govern a particular issue
area or subject matter. In their initial study, for example, Raustiala and
Victor analysed the regime complex for plant genetic resources, that is, the
interplay of different institutions such as the World Intellectual Property
Organization (WIPO), the Agreement on Trade-Related Aspects of Intellec-
tual Property Rights (TRIPS), and the United Nations (UN) Convention on
Biological Diversity, speaking to the problem of property rights for plant
genetic resources (ibid: 283–4).
The concept of a regime complex stresses three necessary features (Alter
and Meunier 2009; Keohane and Victor 2011; Orsini et al. 2013; Zelli 2011;
Alter and Raustiala 2018): (1) two or more separately created elemental
institutions with (2) overlapping membership (Hofmann 2011), that
(3) speak to the same issue area, problem, or subject matter. On this basis,
scholars have increasingly analysed the governance of a given problem or
subject matter by mapping the complex of international and transnational
agreements, their interplay, and how the interplay affected outcomes, with a
view to the problem-solving capacity of inter-state cooperation. While
regime complexity may also be seen as a systemic feature of world politics,
3
It should be added, however, that the original regime framework already allowed looking at
different IOs governing one issue area.
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regime complexes as understood in this literature operate at a meso-level of
societal organisation, not at the macro-level of the global governance system
as a whole (see also Faude and Gehring 2017: 186).
One key question addressed in the regime complexity literature is how
regime complexes are structured and how their structure impacts the
problem-solving capacities regarding the respective issue. Here, most con-
tributions have taken given issue areas or governance problems as starting
points to map the web of inter- and transnational institutions that overlap in
their claims to authority regarding the regulation of issues such as climate
change (Keohane and Victor 2011; Abbott 2012), security (Hofmann
2011), global refugees (Betts 2009), or intellectual property rights (Helfer
2009). As a consequence, the literature has mostly focused on interactions
between institutions rooted in one and the same issue area. Studies about the
trade–environment nexus are the most notable exception in this regard
(e.g. Eckersley 2004; Biermann et al. 2009; Zelli et al. 2013).
4
In terms of
assessment, these contributions are thus predominantly concerned with the
functionality of the regime complex for solving the problem(s) around
which the elemental institutions converge (see Keohane and Victor 2011;
de Búrca et al. 2014).
The second main question concerns the effects of regime complexity for
strategic interactions. Here, the gist of the literature is that the existence of
multiple and overlapping institutions in an issue area create new options for
states and non-state actors to pursue their interests. On the one hand, it
opens the possibility of institutional choice (Jupille et al. 2013). In an
institutional setting with overlapping claims to regulatory authority, the
rule-addressees may engage in forum shopping to circumvent costly obliga-
tions or foster favourable decisions on specific questions in their interest
(Busch 2007). On the other hand, it also enables actor coalitions that are
dissatisfied with an existing institution to shift the focus of their ‘activity to a
challenging institution with different rules and practices’(Morse and Keo-
hane 2014: 388). This practice is referred to as regime shifting (Helfer 2009)
or more broadly as contested multilateralism (Morse and Keohane 2014;
Kreuder-Sonnen and Zangl 2016)orcounter-institutionalization (Zürn
2018: Ch 7).
5
On that basis, the literature has so far tended to stress the
4
Somewhat ironically, another prominent exception is the original study by Raustiala and
Victor (2004), who analysed overlaps between institutions rooted in different issue areas and with
divergent social purposes, namely trade (focusing on the protection of intellectual property) and
biodiversity (focusing on the protection of natural resources).
5
These concepts also include cases of competitive regime creation in which dissatisfied actors
first establish the alternative institution to which they then shift their focus. However, this is not a
structural effect of regime complexes because it does not presuppose a preexisting institutional
complex.
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problems created by regime complexity for an international order based on
law. Arguably, it propels a shift from law-based to power-based outcomes
by providing powerful states with additional opportunities to pursue their
parochial interests through inter-institutional strategising (Drezner 2013;
see also Faude and Gehring 2017: 187).
To sum up, the regime complexity framework has produced a rich
research programme on the meso-level of global governance arrangements
in the confines of single issue areas or subject matters. Research in this
tradition is predominantly centred on the question of either the effects of
regime complexes on problem-solving capacities or the strategic opportu-
nities they open for actors. Such an approach is valid and important to
understand the effects of institutional interplay for problem solving and
distributional effects.
Shortcomings: The need for a micro-level approach
While both frameworks outlined above have spurred a rich and insightful
research programme, they also have some limitations and blind spots. Most
importantly, they have largely worked on assumptions of inconsistency or
complementarity between the norms that overlapping institutions embody.
Much less attention has been paid to the question of what actually happens
at the interface of the fragments that compose the international legal system
or between the elemental institutions that compose a regime complex. Do
overlaps really result in interface conflicts? If yes, when? And how, if at all,
are colliding norm sets handled empirically? We suppose that the neglect of
these questions is tied to a second problem of both the fragmentation and the
regime complexity framework, namely their reliance on an externalist
approach to the identification of normative incongruence. That is, whether
an overlap exists and whether it is conflictual or not is determined by the
researchers from the outside, mostly relying on legal analyses. However, it is
possible that actors see or construct norm collisions where analysts do not,
and it is possible that analysts see conflicting norms, but actors do not. In our
perspective, institutional overlap constitutes a problem only to the extent
that at least one collective social actor (interest group, civil society organi-
sation, state, or IO) challenges the validity or interpretation of an interna-
tional norm or rule by referring to the prevalence of another norm or rule.
Conflicts need to become activated via contestations in practice or speech
acts. Such a focus on the actors’own perception or construction of norma-
tive incompatibility is at the core of our internalist approach to the identi-
fication of conflict.
The concentration on the handling of actors’positional differences at the
interstices of legal fragments or elemental institutions not only highlights a
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different element of the phenomenon, but it also represents a missing link for
answering key questions in the original debates on fragmentation and
regime complexity. Only if we know how conflicts are dealt with –that is,
if and how they are managed –can we understand and demonstrate the
mechanisms by which the deliberate or unintentional creation of institu-
tional overlaps translates into eventually harmful or beneficial conditions
for the international order and for explaining strategic interactions therein.
As Michaels and Pauwelyn (2011: 31) put it: ‘Whether international law
behaves like a system or not is in no small part determined by the very way in
which relations between rules are handled.’Moreover, answers to these
questions are necessary to determine the empirical conditions upon which
the normative visions for the global legal order are to be based. Where the
system of international law is headed –that is, in a more constitutionalist or
a more pluralist direction –and what normative response it should give rise
to depends on comparative empirical analyses at the micro-level of conflicts,
of which we assemble an initial batch in this Special Issue. By doing so, we
contribute to a newly emerging literature that says ‘farewell to fragmenta-
tion’(Andenas and Bjorge 2015) as the structural concept of interest and
puts emphasis on the ways in which courts, tribunals, and other actors have
developed legal and political techniques to coordinate the different subfields
of international law (Peters 2017; Meggido 2019).
III. The interface conflict framework
In contrast to the macro-level approach of the fragmentation framework
and the meso-level approach of the regime complexity framework, our
interface conflict framework zooms in on the micro-level of conflict between
actors. We foreground questions relating to how actors perceive or even
construct norm inconsistencies, to whether and when they avoid or enter
into open conflict over the prevalence of overlapping norms, and to if and
how such conflicts are managed.
6
It thus provides the basis for an integrated
and inter-disciplinary research programme on institutionalised cooperation
after fragmentation.
In the remainder of this introduction, we develop the analytical model
underlying the interface conflict framework that the contributions to this
Special Issue fill with life. Figure 1 sketches the model in a schematic fashion.
It consists of a sequence of variables or concepts that we assume to be
6
In our endeavour to study the avoidance and management of norm-collisions, we build on
and contribute to related literature on interplay management, which ‘refers to the conscious
efforts by any relevant actor or group of actors, in whatever form or forum, to address and
improve institutional interaction and its effects’(Oberthür and Stokke 2011: 6).
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causally linked. It starts with institutional overlap and norm collisions and,
through conflict activation and conflict management, leads to effects on
global order. While the order of variables in the chain is logically deter-
mined, we accept that in real-world cases some steps in the causal chain can
be circumvented. For instance, norm collisions or institutional overlap can
incite (pre-emptive) conflict management without first creating an open
interface conflict and some interface conflicts may directly affect the global
order without running through conflict management. We spell out the
relationship of these concepts more fully in the following sections and
highlight some of the main findings in the contributions.
Core concepts
The central concept around which our framework revolves is that of interface
conflicts. It denotes those norm collisions beyond the nation state that are
perceived or constructed by actors and expressed in positional differences.
We are interested in the causes of interface conflicts and in their consequences.
Interface conflicts can thus be both an analytical starting and end point. They
represent a starting point inasmuch as we are interested in how interface
conflicts are acted upon –that is, if and how they are managed –and what
consequences the conflict management has on the global order. On the other
hand, they are also end points to the extent that we inquire into the conditions
under which interface conflicts come about or can be avoided.
In order to approach these questions, it is first of all necessary to develop a
clear-cut conceptualisation of interface conflicts. In general, interface conflicts
Instuonal
overlap and/or
norm collision
Interface conflicts
Conflict
management
Effects on
global order
Context: Institutional density
Figure 1: Analytical model of interface conflict framework
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refer to a subset of norm collisions arising in global governance. We include
only collisions between norms emanating from different institutions, at least
one of which being an international authority. This conceptual scope allows
us to study both horizontal conflicts pitting norms from two international
institutions against each other, and vertical conflicts in which domestic and
international norms collide. But how do we know when we see an interface
conflict? The literature has so far tended to adopt a formalistic approach
according to which the legal community establishes conflicts by determining
the correct legal interpretation of the norms in question (see Wisken 2018:Ch
2). By contrast, our conceptualisation takes a sociological perspective and
sees interface conflicts not as objectively given. Before we speak of conflicts,
they must be constructed and perceived as such by relevant actors and
expressed in form of incompatible positional differences about means or
goals (see Dahrendorf 1961;Coser1964). Importantly, this also implies that
interface conflicts may ariseirrespective of whether the norms invoked by the
conflicting actors previously were colliding according to legal observers. We
thus give priority to the internal perspective on conflict.
In sum, then, we speak of an interface conflict when relevant actors
perceive rules to diverge in such a way that the simultaneous attainment
of their regulatory objectives is seen to be incompatible or unattainable, or
when they purport such an incompatibility to pursue their interests. In other
words, interface conflicts are defined as incompatible positional differences
between actors about the prevalence of two or more norms or rules ema-
nating from different institutions. In these interface conflicts, different
positions are justified with reference to different norms and rules of which
at least one is associated with an international authority.
A prominent example of an interface conflict is the dispute over the UN
Security Council’s (UNSC) regime of targeted sanctions against terror sus-
pects. Here, positional differences were expressed over the question of
whether and to what extent the UNSC should be obliged to grant due
process rights to the targeted individuals. One actor coalition, including
the United States and the UNSC as a whole, referred to the special powers
granted to the UNSC in the UN Charter for the maintenance of international
peace and security to argue that no such obligation existed. Another actor
coalition, comprising in particular European and domestic courts, the UN
Human Rights Committee, the Parliamentary Assembly of the Council of
Europe, several NGOs, and a group of European states, held that basic –if
not the full range of –due process standards had to be adhered to by the
UNSC when targeting individuals. They justified their position by reference
to international, and particularly European, human rights norms (Krisch
2010: Ch 5; Heupel 2013, 2017; Kreuder-Sonnen 2019: Ch 4).
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Indeed, the case is well-rehearsed also in the fields of fragmentation
(Ziegler 2009) and regime complexity (Morse and Keohane 2014). From
the perspective of our approach, however, it highlights the necessary
features of interface conflicts that are a) actors with positional differences
who b) justify their respective stance with reference to different international
norms that are c) connected to different international authorities. This
notion is more restrictive than the situations covered in the alternative
accounts. For example, the creation of the New Development Bank
(NDB) and the Asian Infrastructure and Investment Bank (AIIB) alongside
the World Bank is widely cited as building a regime complex of development
banking that undermines the hitherto stable rules of development financing
(Heldt and Schmidtke 2019). However, upon closer inspection, we see that
the regime complex so far has not activated interface conflicts. None of the
relevant actors have brought the rules of one institution in collision with
those of another institution (see Faude and Fuß, this issue). In the same vein,
the competing jurisprudence of the International Court of Justice and the
International Criminal Tribunal for the former Yugoslavia on the question
of state responsibility for non-state actor violence –the famous ‘effective
control’versus ‘overall control’standards –are treated by the ILC (2006:
paragraphs 49–52) as a prime example of fragmentation through conflicting
interpretations of general law. It is a completely different question, however,
whether such a ‘prima facie conflict’(ILC 2006: paragraph 21) is also
activated by actors seeking to justify positional differences by referring to
competing norm interpretations.
To sum up the conceptual discussion: While the interface conflict frame-
work does not introduce a completely new type of phenomenon, it proposes
a new analytical lens that centres on guiding questions, a unit of analysis,
and empirical expectations that are distinct from those taking centre stage in
the fragmentation and regime complexity frameworks (see Table 1). On this
basis, we move on to discuss some of the implications of this framework and
our findings.
From overlap and norm collisions to interface conflicts
Afirst set of issues arises regarding the first arrow in our model that
connects institutional overlaps and norm collisions with interface conflicts
(see Figure 1). We expect that interface conflicts most often are based on
previously existing institutional overlaps or norm collisions that were not
(yet) openly expressed in actors’positional differences. Institutional overlap
can broadly be defined as different transnational and/or international insti-
tutions with prescriptive norms and rules that speak to the same issues and
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have an intersecting membership. Whether and when such overlaps are
turned into interface conflicts is an open question addressed by Faude and
Fuß in this issue. Norm collisions, on the other hand, can be defined as an
incompatibility of two norms due to colliding expectations about appropri-
ate behaviour (see Gholiagha et al., this issue). In this understanding, actors
may individually or dialogically problematise a perceived inconsistency
between two norms without, however, justifying incompatible positions
by reference to the colliding norms. As Gholiagha et al. show in this issue,
norm collisions can long predate interface conflicts. Only when they are
activated do they translate into actors’positional differences.
Taking interface conflicts as an analytical end point, the contributions to
this Special Issue produce some important findings. Most importantly, the
number of norm collisions and institutional overlaps is far greater than that of
interface conflicts –that is, intersecting norms and institutions do not always
lead to conflict among actors. Gholiagha et al. show in their contribution that
the activation of norm collisions often is a matter of political choice and it is
subject to scope conditions such as the power distribution in the political
system. For example, the prohibition of coca leaf chewing in the international
drug control regime had long been seen as colliding with indigenous rights,
especially by political actors from Bolivia. However, it took decades before
the collision was transformed into an interface conflict at the international
Table 1. The analytical frameworks compared
Level of
analysis Approach
Identifi-
cation of
conflict Focus
Expected
consequences
Fragmentation Macro Normative Externalist Global order;
Techniques of
legal conflict
resolution
Legal incoherence;
Legal conflict
resolution
Regime
complexity
Meso Descriptive Externalist Cross-
institutional
strategising;
Problem-
solving
capacity
Distributional
struggle;
Division of labour
Interface
conflict
Micro Descriptive
and
normative
Internalist Interface
conflicts;
Conflict
management
Cooperative or non-
cooperative
conflict
management
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level (Gholiagha et al., this issue). Moreover, Faude and Fuß argue that
institutional overlaps only lead to interface conflicts if the motivation for
the creation of overlapping institutions emanates from substantive policy
dissatisfaction. In other cases, inter-institutional coordination or at least the
peaceful co-existence of the overlapping institutions is more likely (Faude and
Fuß, this issue). The flipside of these findings is that the transition from
overlap/collision to conflict appears to happen predominantly for instrumen-
tal reasons. Interface conflicts are not just an unintended side product of an
increasing institutional density at the international level. Therefore, they can
also hardly be prevented by institutional means. The types of interface
conflicts and the ways in which they are addressed thus become all the more
important objects of study.
Moreover, we hold that one important dimension to distinguish interface
conflicts, which is consequential also for conflict activation and management,
is their bone of contention. Here, we aim at broadening the research agenda
related to international institutional density beyond the narrow focus on
issue-area specific overlaps and sources of conflict to encompass also veritable
goal conflicts. Such conflicts are possible when norms collide that are rooted
in fundamentally different social purposes. Therefore, we distinguish between
interface conflicts occurring within and across spheres of authority (Zürn
2017). We define a sphere of authority as a governance space with at least one
domestic or international authority, which is delimited by the involved actors’
perception of a common good or goal at a given level of governance. Spheres
of authority are different from both issue areas and regime complexes.
While the confines of issue areas and spheres of authority overlap, they are
conceptually independent. Issue areas are marked by the perception of a
connected set of problems that links actors and stakeholders (Keohane and
Nye 1977). The problem of cross-border trade is an example. However,
among the actors and stakeholders in this issue area, there can be a funda-
mental disagreement about what the problem entails and how it should be
approached and tackled. There can be actors and institutions advancing free
trade by reducing tariffs and non-tariff barriers to trade. However, there can
also be actors and institutions that stand for protectionism and the reduction
of cross-border flows of goods and services. They all belong to the issue area.
A sphere of authority, by contrast, unites actors and institutions (at least one
of which is an authority) that share a common sense of purpose. The World
Trade Organization (WTO), for example, is at the centre of an international
sphere of authority comprising a diverse set of actors and institutions with
the goal of enabling and regulating free trade.
As such, a regime complex can indeed form the institutional core of a
sphere of authority as long as one of the institutions in the complex is an
authority. However, as the example of the regime complex of plant genetic
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resources shows, a regime complex can also comprise institutions rooted in
different spheres of authority, such as the WTO (free trade) and the UN
Convention of Biological Diversity (Raustiala and Victor 2004). The con-
cepts are thus different. While the WTO can be part of myriad regime
complexes governing certain subject matters bordering trade, it remains
part of only one sphere of authority with an identifiable social purpose,
namely free trade. What is more, spheres of authority can also be identified
at a lower governance level than regime complexes. A set of domestic actors
and institutions clustering around an authority with a nationwide goal of,
say, energy transformation also qualifies as a sphere of authority. This
highlights the potential of overlaps (and conflicts) between domestic and
international spheres of authority that are missed by the regime complexity
framework.
The conceptual lens of spheres of authority allows us to study and
compare conflicts between actors who bring to bear norms emanating from
one and the same or from different spheres of authority. The distinction is
important because we expect significant differences regarding both the
activation and management of interface conflicts. Given the overall goal-
alignment of institutions in within-sphere conflicts, positional differences
should normally relate to turf battles over resource allocation and institu-
tional prevalence (interest conflicts), or to conflicts over means, not to
fundamental normative disagreement. In across-spheres conflicts, by con-
trast, the colliding norms reflect fundamental goal conflicts over the question
of according to which social purpose a certain subject matter should be
governed (conflict over values). Indeed, the contributions to this Special
Issue lead to the conclusion that overlaps and norm collisions within a
sphere of authority get transformed into interface conflicts less often than
those involving norms and institutions from two different spheres. To the
extent that we observe active conflict pre-emption, it takes place within a
sphere of authority. In fact, the one case of overlap studied by Faude and Fuß
(this issue) that leads to an interface conflict is the one where two competing
social purposes (energy security and climate change prevention) are at play.
Moreover, interface conflicts seem more likely to be managed cooperatively
when they take place within a sphere of authority. It is especially courts that
may develop secondary norms and rules to manage interface conflicts
smoothly. Most existing courts are, however, bound to one sphere of
authority. In general, the management of interface conflicts across different
spheres of authority can thus be expected to be more difficult. Nevertheless,
some contributions to this Special Issue show that also across-sphere con-
flicts can be successfully managed. Birkenkötter (this issue), for instance,
highlights that general international law may serve courts as a tool to legally
address conflicts cutting across spheres of authority.
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Conflict management
A major implication of our approach is that we are less interested in
institutional density as such. In fact, we consider institutional differentiation
to be a defining feature of any modern society, be it on the national or the
global level. In this sense, institutional density cannot be understood as
fragmentation (the falling apart of something that was once an integrated
whole), and the rise of institutional density is nothing that is by itself
conducive or unconducive to problem-solving. The decisive question is
whether and by what principles interface conflicts are managed once they
arise. With this question, we move to the second arrow in our analytical
model (see Figure 1).
Here, we are especially interested in the conditions under which
interface conflicts are handled cooperatively or non-cooperatively. We
suppose that conflicts regularly involve some form of conflict manage-
ment (see Rittberger and Zürn 1990). According to Zelli (2011:207),
management of interface conflicts can be defined as ‘any deliberate
attempt to address, mitigate, or remove any incompatibility between
the [norms] in question’. These attempts are in no way predetermined to
be rational, balanced, or technical. Just as the conflict itself, its manage-
ment can be highly political. The concrete form of the management
attempts is then an empirical question, which should be telling with
regard to the functioning and the normative structure of the emerging
global governance system.
For the purposes of this Special Issue, we most basically distinguish
between cooperative and non-cooperative forms of conflict management.
We speak of non-cooperative conflict management when the conflict
parties seek to resolve the dispute in their favour without regard for the
preferences of their opponent and without following procedural norms. By
contrast, cooperative conflict management refers to attempts to address an
interface conflict in which the conflict parties agree to follow procedural
norms and/or accommodate each other’s preferences at least somewhat in
their respective position. Within the category of cooperative conflict man-
agement, we furthermore differentiate three subtypes according to their
degree of regulation. We consider cooperative conflict management to be
constitutionalised if it takes place within institutionalised procedures pro-
viding norms of meta-governance to authoritatively solve interface con-
flicts. Second, norm-based conflict-management describes a handling of
interface conflicts with reference to third norms –that is, norms that are
different from the two norms in collision. Such norms may be substantive
(e.g. higher-ranking normative principles such as sustainability) or proce-
dural (e.g. rules of precedence or applicability). Finally, we speak of
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decentralised cooperative conflict management if the conflict is not referred
to a third party and actors do not take recourse to third norms, but when
they still show a willingness for mutual accommodation and political
compromise in the process of handling positional differences. This orien-
tation towards compromise may show in actors’acceptance of certain basic
procedural norms and/or the at least rhetorical embrace of some common
norms. An orientation towards compromise is also indicated if actors
adapt their behaviour –actively or tacitly –to reduce positional differences
by taking other positions into account.
The studies in this Special Issue show quite impressively that fully non-
cooperative forms of conflict management are rare. In fact, all contribu-
tions focusing on the management of interface conflicts find that actors
respond to conflicts at least moderately cooperatively. While none of them
finds indications for a constitutionalised system of conflict management,
especially Birkenkötter (this issue) highlights that interface conflicts can be
referred to third parties –that is, courts –that implement norm-based
conflict management by solving legal disputes with reference to (mostly
procedural) third norms. Others find conflict management to be much less
regulated but still cooperative. For instance, Krisch et al. (this issue) show
that conflicts over human rights in World Bank policies and UN rules of
Corporate Social Responsibility have not been addressed through third
parties or third norms. Nevertheless, the decentralised norm-based contes-
tation between the conflict parties has led to a tacit accommodation of
human rights norms in the adjacent institutions and thus significantly
reduced the norm incoherence (see Krisch et al., this issue). Even in the
field of internet governance where Flonk et al. (this issue) trace protracted
interface conflicts between competing liberal and sovereign spheres of
authority, actors’conflict handling is characterised at least by the accep-
tance of basic procedural norms and an interaction mode of norm-based
argumentation indicating at least some compromise orientation. Overall,
we can conclude with Krisch et al. (this issue: 360) that often ‘norm
collisions are not antithetical to order but creative of it’.Inthissense,
Dahrendorf (1961) may have been right to emphasise that conflicts are the
‘creative core of all societies’.
The choice of conflict management, in turn, seems to depend on the types
of underlying conflicts and scope conditions. For instance, it seems to be
conflicts over underlying values that are especially difficult to manage,
which might also be one of the reasons why interface conflicts between
different spheres of authority are less likely to be managed on the basis of
third norms. In these cases, decentralised forms of conflict management
prevail (e.g. Krisch et al., this issue; Flonk et al., this issue). Conflict
management, however, is not fully predetermined by conflict types. Scope
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conditions –such as the power distribution among the involved parties and
their general attitude towards each other –as well as the role that trans-
national actors and third parties play are decisive.
Effects on global order
Moving to the third arrow in our model –from conflict management to effect
on global order (see Figure 1)–it is fair to state that the diffusion of interface
conflicts leads to neither constitutionalisation nor fragmentation. Coopera-
tive conflict management of interface conflicts prevails, but it falls short of
creating a strong and legally systematic apparatus of secondary norms that
cut across spheres of authority. Norm-based cooperative conflict manage-
ment in which the actors resort to third norms to address the conflict is the
most order-generating type of conflict management observed. Since it typi-
cally incites the creation of future-oriented interface norms, it does introduce
some secondary norms into the global governance system that support the
building of an inter-institutional order (e.g. Birkenkötter, this issue). How-
ever, also decentralised forms of conflict management may establish norma-
tive guideposts for mutual adaptation (Krisch et al., this issue). This is
particularly true for instances of pre-emptive conflict management in which
the coordination of potentially conflicting norms and institutions may lead to
normative alignment or a sustainable division of labor (Faude and Fuß, this
issue; see also Flonk et al., this issue). In this sense, the rise of interface conflicts
does not necessarily undermine the global legal order.
At the same time, the mere absence of chaos or disorder in an institution-
ally dense international environment does not say much about the norma-
tive quality of the inter-institutional order emerging from the handling of
potential and actual interface conflicts. From a constitutionalist perspective,
in particular, we have to bear in mind that the normative substance of the
global legal order can be liberal but also illiberal (see also Kreuder-Sonnen
and Zangl 2015). It is possible to think of an international order that
contains strong interface norms for norm collisions but is not liberal at
all. An interface norm that systematically puts state rights over individual
rights may resolve many interface conflicts, but it certainly makes the
international order less liberal. A prime example for this kind of illiberal
order building is provided by Moe and Geis (this issue). In the realm of
African security governance, interface conflicts over the prevalence of sov-
ereignty and humanitarian intervention between the UNSC and the African
Union (AU) have given way to a mutually accepted division of labour. After
the terrorist attacks on 11 September 2001, the paradigm of liberal inter-
ventionism was incrementally replaced by the notion of stabilisation mis-
sions, which tend to subjugate the goal of protection of individuals to that of
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protection of political order. While this shift allowed the UN and the AU
to more cleanly divide tasks of mandating and enforcement on the ground
and thus to increase inter-institutional order, Moe and Geis (this issue) show
that this order is highly detrimental to human rights protection on the
ground.
While there is no theoretical reason to expect the settlement of interface
conflicts to systematically show illiberal traits, the example highlights that
the normative direction of the international legal order is indeterminate.
What is more, the contributions to this Special Issue show that most interface
conflicts arise out of actors’desire to contest a given institutional or nor-
mative status quo –they are not normally accidental or inevitable. Since
much of the global order has at least a veneer of liberalism rooted in post-
war Western dominance (Ikenberry 2011), it is not far-fetched to claim that
interface conflicts often serve as instruments to contest (overly) liberal
aspects of the order and/or to undermine the preponderance of established
(Western) powers in international institutions. Most prominently, this
dynamic can be observed in the interface conflicts unfolding in the domain
of internet governance (see Flonk et al., this issue). While actor coalitions
and interest constellations are more complex, the article shows that the
proponents of a sphere of sovereign internet are led by rising powers
contesting the preponderant sphere of liberal internet, which is centred on
Western institutions and human rights norms (Flonk et al., this issue).
Evidently, norm contestation through interface conflicts can also be pro-
gressively geared towards an enhancement of liberal values (e.g. Krisch et al.,
this issue). Yet, given the current distribution of power in international
institutions and their value orientations, we expect that, more often than
not, norm collisions will be activated to contain and not to reinforce the
liberal aspect of global order.
The effects of international institutional density and the rise of interface
conflicts on the constitutional quality of the global order thus are important
but indeterminate. We expect that real-world interface conflicts lead to
conflict management that entails complex and contradictory configurations
of consequences for the normativity of global order. After fragmentation thus
does not mean before constitutionalisation. It stands for a global political
system that consists of spheres of authority that are loosely coupled in varying
ways with different implications for the normative quality of global order.
IV. Contributions
The contributions to this Special Issue tackle three major questions that lie at
the core of the interface conflict framework: a) under what conditions
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interface conflicts arise, b) if and how interface conflicts are managed, and c)
what effects interface conflicts and their variable handling have on the global
order. Faude and Fuß as well as Gholiagha et al. provide answers to the first
question. The contribution by Faude and Fuß inquires into the conditions
under which deliberately created institutional overlaps result in interface
conflicts. Studying institutional overlaps in the fields of development bank-
ing, climate change, and energy, Faude and Fuß show first of all that not all
overlaps translate into interface conflicts. Second, they argue that whether
this happens very much depends on the motivation for creating overlapping
institutions in the first place. If dissatisfaction with procedural rules or the
governance effectiveness of the institutional set-up is the reason for bringing
in overlapping institutions, Faude and Fuß expect coordination among the
institutions. Only if the overlap is created due to dissatisfaction with sub-
stantive policies, they argue, is it likely to spur veritable conflict.
Similarly, Gholiagha et al. start from the assumption that there are norm
collisions –that is, subjectively or intersubjectively perceived normative
incompatibilities –which are not yet nor will necessarily become actual
interface conflicts. In their view, norm collisions need to be activated by
actors who employ the colliding norms to justify incompatible political
positions and to induce a policy change. Analysing the discourse in the issue
area of international drug control, Gholiagha et al. show that a norm
collision between indigenous rights and the prohibition of coca leaf chewing
existed for decades before it was activated by Bolivia, the UN Permanent
Forum on Indigenous Issues, and the International Narcotics Control Board
in the late 2000s. Zooming in on the question of the conditions under which
norm collisions are turned into interface conflicts, Gholiagha et al. extrap-
olate three main factors that were conducive to the activation of the norm
collision regarding coca leaf chewing and that are expected to be more
general scope conditions for the translation of norm collisions into interface
conflicts: the decline of hegemony, the mobilisation by advocacy coalitions,
and a (health) crisis.
Birkenkötter starts to move from the analysis of the emergence of interface
conflicts to the analysis of conflict management. Concretely, her contribu-
tion studies the role of international law as a conflict management tool in
interface conflicts that end up in front of a court or court-like third party. As
Birkenkötter argues, international law provides a common language that
cuts across spheres of authority and provides commonalities of legal form
that regulate conflict management in recurrent ways. On the one hand, when
conflict management involves international courts or court-like institutions,
the conflict parties are tied to specifically legal arguments. That is, when
referring to norms, they must make an effort to argue why that norm should
be legally binding and not merely be morally persuasive. On the other hand,
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judicial or quasi-judicial third parties may then resort to legal norm-conflict
resolution rules such as lex specialis or lex posterior, or also broader rules of
justification and excuses such as the principle of proportionality. Overall,
Birkenkötter makes the claim that international law can function as a legal
conflict resolution tool, but that it is strongly limited in scope and further-
more unlikely to appease the underlying political conflict.
In their contribution, Krisch et al. look at more decentralised management
of interface conflicts, that is, without third party involvement. While the
literature tends to highlight the conflict potential of mostly rivalrous norm
collisions that are not subject to more regulated conflict management, Krisch
et al. argue that interface conflicts are often rather of irritative nature and
thus not destabilising but transformative of order –an effect that becomes
visible when the conflicts and their management are observed over longer
periods of time and not as momentary snapshots. According to Krisch et al.,
conflicts are irritative if they imply a normative challenge to the existing
institutional or normative status quo that is not meant to replace the original
norms and institutions or to play one of them out against the others, but to
induce normative change in the existing body of norms. Since irritation may
be met with gradual adjustments, it is more conducive to cooperative conflict
management than rivalry. This claim is illustrated in two case studies of the
handling of interface conflicts related to the relationship between human
rights norms and World Bank policies and procedures as well as UN norms
of Corporate Social Responsibility.
In the field of internet governance, Flonk et al. analyse a sequence of
interface conflicts in varying institutional settings and partially varying actor
compositions, but with a broadly consistent object of contention: the ques-
tion of whether the internet should be governed by mostly Western, multi-
stakeholder institutions embodying liberal norms of individual freedom or
by mostly non-Western, intergovernmental institutions embodying sover-
eigntist norms of national security and territorial integrity. Flonk et al. frame
this as a goal conflict across two emerging yet competing spheres of author-
ity, one liberal and one sovereigntist. Reflecting the deep-seated conflict over
values that is underpinning this struggle, conflict management has so far
remained rather sketchy and has not yet led to a sustainable settlement
among the conflict parties. Nonetheless, the contribution by Flonk et al. also
shows that, even in such a rivalrous setting, interface conflicts are not
necessarily addressed by means of fully uncooperative conflict management.
Finally, Moe and Geis provide a critical reflection on the consequences of
conflict settlements for the global order. Focusing on the field of security
governance in Africa, the contribution traces the development of the inter-
organisational relations between the UNSC and the AU over questions of the
interventionary use of force. Moe and Geis find that interface conflicts
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pitching norms of human rights protection against sovereignty and non-
interference were common during the heydays of liberal interventionism in
the 1990s. After the terrorist attacks of 11 September 2001, however, Moe
and Geis argue that the macro-securitisation through the global war on
terrorism has led to a shift in priorities that put stabilisation missions higher
up on the agenda than humanitarian interventions. As a consequence, the
main normative bone of contention between the UN and the AU has waned,
because stability-driven interventionism allowed for a pragmatic division of
labour. While the UN retained the mandating authority, it increasingly
delegated the often more robust enforcement measures to the regional
organisation. While this cooperative outcome is indicative of the building
of inter-institutional order, Moe and Geis highlight that it comes at a cost to
liberal values, since human rights have been relegated to second rank in the
preoccupation to secure political stability.
The Special Issue is concluded by two critical commentaries by Karen
Alter and Siddharth Mallavarapu.
Acknowledgements
Earlier versions of this article were presented at the 2018 General Conven-
tion of the German Political Science Association in Frankfurt, the 2019
Annual Convention of the International Studies Association in Toronto, and
two authors’workshops with the contributors to this Special Issue. We would
like to thank the participants in these forums for their valuable comments, in
particular Kenneth Abbott and Andreas von Staden. We are furthermore
grateful to two anonymous referees for their constructive feedback, to Barcin
Uluisik for language editing, and to Joia Buning for research assistance.
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