Unilateralism (PIL)

From Max-EuP 2012

by Giesela Rühl

1. Introduction

Private international law (PIL) deals with the question of which law applies in cases that have connections to more than one legal order. To answer this question, essentially two methods are available: the unilateral method dating back to the Middle Ages on the one hand, and the multilateral method established in the 19th century by Friedrich Carl von Savigny on the other. The methods are fundamentally different. Whilst unilateralism begins with the norm and determines whether it demands application to a particular legal relationship, multilateralism begins from the legal relationship and assigns it to a particular legal order with the help of choice of law rules. In Europe, the multilateral method has dominated since the 19th century. The unilateral method is predominant in the United States.

a) Theoretical departure point

The distinction between unilateralism and multilateralism finds its origin in the understanding of the nature and the function of private law: for unilateralism, private law—like public law—is an expression of state sovereignty. It effectuates state interests and fulfils social functions. Cases with ties to multiple legal orders are, from this perspective, conflicts between states and state interests. It follows almost inevitably that determination of the applicable law must start from the statutory provisions in question and refer to the values and functions of substantive law as well as the intentions of the legislature. The situation looks different from the perspective of the multilateral method: for multilateralism private law—unlike public law—is neutral and apolitical. It does not incorporate state interests and has no socially constitutive functions. Instead, it orders personal activities and freedoms and regulates interests of private parties. Cases with ties to multiple legal orders are, therefore, not a matter of conflicts between states and state interests but clashes between private intentions and individual spheres of freedom. The determination of the applicable law is thus a balancing of private interests and is undertaken with the help of general choice of law rules without consideration of legislative intent or the function of the respective substantive laws. And even though multilateralism determines the reach of domestic and foreign law, it does not at the same time impair the sovereignty of the relevant states. Since private law is free of state interests, deter- mination of the reach of foreign norms cannot injure state interests. Given the neutrality of private law, the relevant rules are fundamentally equal and exchangeable.

b) Practical implications

The distinction between unilateralism and multilateralism has more than mere theoretical meaning. The founder of the multilateral method, Friedrich Carl von Savigny, assumed that multilateralism would regularly come to the same result as the unilateral method. But for the judges trusted with the determination of the applicable law, the differences are enormous. On the basis of unilateralism, the judge determines the applicable law in two steps: in the first step he must decide which law demands application by interpreting the relevant substantive norms. Since the determination of each law takes place separately, it might happen that the laws of various states claim applicability. In such a case the judge must establish which of these laws has priority. On the basis of multilateralism, the judge ascertains the applicable law largely in one step starting from the legal relationship. With the help of general, previously determined criteria, he assigns this legal relationship to a particular substantive law without asking whether this law demands application.

All things considered, unilateralism thus poses greater challenges and practical difficulties for the judge than multilateralism. This is because a court seized in a cross-border case must look into all potentially applicable laws and determine those laws’ interest in being applied. However, courts have neither the necessary (comparative law) education nor the necessary resources. Unilateralism, therefore, runs the risk of producing arbitrary and, for the parties, hardly foreseeable results. The multilateral method, in contrast, avoids these problems. It therefore contributes to legal certainty and can claim greater practicality.

2. Historical development

a) The medieval statutists’ method

Unilateralism in private international law finds its origin in the medieval statutists’ method. It was developed in the 12th century by Upper Italian courts and scholars to determine the applicable law in disputes between citizens of various northern Italian states. On the basis of the Corpus Juris Civilis and the lex cunctos populos set out therein, it was assumed that the spatial reach of local norms, the so-called statutes, was limited. The jurists tried to determine the reach of local norms by creating different categories of norms. To begin with, they distinguished between norms pertaining to the person (statuta personalia) and norms pertaining to the territory (statuta realia). Provisions pertaining to the person were to be applied to the citizens of a state, even independent of their location. Provisions concerning the territory were applicable to persons who remained for six months within the relevant city walls. Later, mixed provisions (statuta mixta) were added, which could not be unequivocally categorized.

The statutists’ method dominated European private international law—with differences in detail—up until the 19th century. Nevertheless, it did not manage to create generally accepted criteria for categorizing local norms. The Upper Italian courts and scholars—just like their French and Dutch successors—took account of the wording of the respective local laws. In part, the categorization was even made on the basis of the first word. Later, the attempt was to honour the actual or supposed intention of the legislature. But, even here, no agreement about the process in individual cases could be achieved. The criteria for the determination of the jurisdictional reach of local laws, therefore, differed from province to province and from town to town. Although private international law was seen as universally valid, there were no universally valid solutions.

b) The classical theory of private international law

The multilateral method can be traced back to Friedrich Carl von Savigny, the founder of the classical theory of private international law. Its basis is to be found in his conviction—corresponding to the spirit of the 19th century—that private law is not a subset of state law and an expression of state power, but a product of civil society. For Savigny, the delineation of various legal orders could, therefore, not start from the substantive law in question. Instead, the analysis had to begin with the legal relationship. After all, if private law is neither part of the state order nor an expression of state power, but rather an expression of the people and of individual will, conflicts between legal orders do not appear as conflicts between sovereign states, but as conflicts between areas of individual will or spheres of freedom. And if law is an expression of the people and of individual will, legal relationships must fit spatially into a particular legal area. They must have—in Savigny’s words—a ‘natural home’ (natürliche Heimat), a ‘seat’ (Sitz). For Savigny, the task of private international law was, therefore, to allocate each legal relationship to the legal order where it has its rightful place or ‘seat’. And since he considered private law as a product of civil society, free of state interests and legislative purposes, he aimed at locating legal relationships in the spatially optimal jurisdiction with the help of general criteria but without regard to the content, function and values of substantive law.

The multilateral method presides over the conflicts law in the European legal order up until today. It also applies in the European Community’s recently created choice of law rules. In a slightly altered linguistic form, they state that conflicts between various legal orders are to be solved through application of the law ‘with the closest connection’ to the case. Thus, unlike the United States, where the classical theory of private international law could not, at least not for long, endure and where it only glimmers through in the ‘most significant relationship’ of § 6 Restatement (Second) of the Conflict of Laws (restatements), multilateralism has held its ground in Europe.

c) The political school of private international law

Whilst the multilateralism of the Savigny brand continues to dominate in Europe, unilateralism enjoys considerable popularity on the other side of the Atlantic. In particular, it formed the basis for the so-called political school of private international law, which was founded in the course of the American Conflict of Laws Revolution by Brainerd Currie in the middle of the 20th century. With respect to its structure and orientation, the understanding of private law is, as with Savigny, of decisive significance. Unlike the classical theory, the political school does not see private law as a neutral and apolitical legal zone, free of state interests and social functions. Under the influence of American legal realism, it rather emphasizes its socially formative and purposive character, which assists states in realizing their interests and intentions. For private international law doctrine, this understanding of private law—different from the understanding underlying classical theory—means that conflicts between various legal orders are conceived of as conflicts between various states and their interests. The central problem that private international law must solve is therefore not the discovery of the legal order in which the relevant dispute has its seat. Rather, the concern is the discovery of the legal order with the largest interest in the application of its substantive norms. The determination of the applicable law is therefore—as with the medieval statutists’ theory—dependent on an assessment of the intention of the relevant substantive norms. However, unlike the statutists’ theory, which classified the relevant provisions of substantive law according to their demand to be applied, the political school foresees a judicial investigation and balancing of the affected state interests.

The political school of private international law influences US conflicts law up until today. Next to Brainerd Currie, leading proponents include David Cavers, Robert Leflar, Albert Ehrenzweig, Arthur von Mehren, Donald Trautmann and Russell Weintraub. In Europe, in contrast, the political school has not achieved widespread acceptance. As shown by a glance at the Member States’ private international laws and the provisions issued by the European Union in private international law, the classical theory is dominant. Nevertheless, the political school has left its traces, as it led to a politicization and instrumentalization of multilateral choice of law rules. This is obvious in provisions such as Arts 5 and 6 Rome Convention as well as Arts 6 and 8 Rome I (consumer contracts (PIL); employment contracts, individual (PIL)). These provisions elevate political intentions as well as values and functions of substantive law to the level of private international law and, thus, contribute to their enforcement with the help of multilateral choice of law rules.

3. Modern trends

The fact that multilateralism prevails in Europe—both at the level of the individual Member States and at the level of the European Union—up until today, does not mean that unilateralism has made no impact here. On the contrary, the penetrating state regulation undertaken in the course of the 20th century has increased the number of overriding mandatory provisions and the number of legal areas in which the determination of the applicable law is not dependent on the seat of the legal relationship but on a reading of the legislative intent behind the relevant laws. Since globalization and Europeanization have intensified this trend, the unilateral islands in the sea of multilateral international private law have grown in the last years.

a) Overriding mandatory provisions

Unilateral elements manifest themselves in European conflicts law primarily in the form of overriding mandatory provisions (Eingriffsnormen; loi d’application immédiate; legge di applicazione necessaria). Friedrich Carl von Savigny had already identified them, ‘as laws of strictly positive, compulsory nature’, and they are recognized by the private international laws of the Member States and the European Union—as is shown by Art 9 Rome I (Reg 593/2008) and Art 16 Rome II (Reg 864/2007). They stand out in that they determine their own sphere of application and do so independent of the applicable law that is otherwise established with the help of general choice of law rules.

Exactly when a norm can be categorized as an overriding mandatory norm and thereby, in the manner of unilateralism, determine its own scope of application is a question which eludes a conclusive and generally applicable answer. Basically, overriding mandatory norms can be recognized in that they try to express a public interest in the broadest sense, and, other than norms of classical private law, they do not serve merely to reconcile private interests. Often they are of an economic and socio-political nature and are aimed at regulation of individual areas of social life. In consonance with this broad description, Art 9(1) Rome I Regulation defines overriding mandatory provisions as ‘provisions the respect for which is regarded as crucial by a country for safeguarding its public interests, such as its political, social or economic organization, to such an extent that they are applicable to any situation falling within their scope, irrespective of the law otherwise applicable’. Classic examples are currency mandates and import and export embargoes.

b) International economic law

In the context of the essentially multilateral European private international law, overriding mandatory norms constitute ‘classic’ gateways for unilateralism. Nevertheless, from a methodological point of view they represent exceptions that prove the rule, namely the validity and supremacy of multilateralism. However, this is not the case in international economic law. Here, unilateralism was largely established in the 20th century and, thus, has displaced the multilateral method. The backdrop to this development was, on the one hand, a changing understanding of the state and its role, and, on the other, insights into the limits of the market. Whereas the liberalism of the 19th century, during which the multilateral method of the Savigny school flourished, assumed the unlimited capacity of the market, the events at the beginning of the 20th century brought an awareness of the dangers of an unregulated market. The resulting insight into the necessity of a framework ordering economic activity led to state intervention not only to protect the economy as an institution, but also to protect the individual from the workings of the economy. Since these regulatory interventions were politically motivated and therefore robbed private law of its neutrality, the multilateral method lost currency. The unilateral method, therefore, gained significance in the entirety of international economic law and is today supreme in determining the application of the relevant norms. It is particularly widespread in the area of competition law (competition law (international)). However, large parts of labour law, social law and transport law are also influenced. In contrast to overriding mandatory norms, which—at least theoretically—represent only isolated incidences of unilateral influence, international economic law is widely seen as the territory of unilateralism.

c) Secondary Union law

The unilateralist trend, which is apparent in international economic law, is being seamlessly extended into other areas. Unnoticed by many, unilateralism has infiltrated the secondary private law of the EU. A recent study by Stéphanie Francq into regulations and directives in the areas of competition, transport, consumer, labour and trade representative law shows that the pertaining provisions—expressly or implicitly—define their own spatial reach. In the area of transport law, the Regulation on the air carrier liability in the event of accidents (Reg 2027/1997, altered by Reg 889/2002), for example, mandates that it applies to all companies that are in possession of a licence to operate from a Member State. And in consumer contract law, the Package Holiday Directive (Dir 314/1990) determines that it applies to all package holidays sold within the European Union.

From the viewpoint of conflicts methodology, secondary Union law thus regularly adopts a unilateral approach even in areas not categorized as international economic law. Against this backdrop, a cursory glance at the activity of the European legislature reveals a methodological dualism: while multilateralism prevails in areas that directly deal with the application of laws, unilateralism holds sway in areas that are directly concerned with substantive matters. In this context two points are noticeable: first, unilateralism in secondary Union law is one-dimensional as it only considers and enforces the prescriptions of secondary Union law—and not the prescriptions of national laws. Secondly, unilateralism in secondary Union law is not in accord with the multilateralism of conflicts law regulations. Therefore, the relationship between the unilateralism of Union private law and the multilateralism of Union conflicts law is unclear. Is the current trend towards multilateralism in Union conflicts law inconsistent? Must the role of multilateral choice of law rules in Europe be reconsidered? Which norms take precedence where there is ambiguity? Are the provisions of secondary Union law to be understood as ‘conflicts rules’ of Union law which, according to Art 23 Rome I Regulation and Art 27 Rome II Regulation, take priority over the choice of law rules fashioned in the Savigny mould? Answers to these and other questions must be found in the coming years. It is, however, clear that the dichotomy between multilateralism and unilateralism has not become irrelevant. Consequently, it will continue to colour the future discussion on methodology in private international law.


Brainerd Currie, Selected Essays on the Conflict of Laws (1963); Christian Joerges, Zum Funktionswandel des Kollisionsrechts (1971); Henri Battifol, ‘Le pluralisme des méthodes en droit international privé’ (1973) 139 Recueil des Cours 75; Jürgen Basedow, ‘Wirtschaftskollisionsrecht. Theoretischer Versuch über die ordnungspolitischen Normen des Forumstaates’ (1988) 52 RabelsZ 8; Friedrich K Juenger, Choice of Law and Multistate Justice (1993); Jürgen Basedow, ‘Conflicts of Economic Regulation’ (1994) 42 Am J Comp L 423; Rudolfo de Nova, ‘Historical and Comparative Introduction to Conflict of Laws’ (1996) 118 Recueil des Cours 433; Symeon C Symeonides (ed), Private International Law at the End of the 20th Century: Progress or Regress? (2000); Stéphanie Francq, L’applicabilité du droit communautaire derivé au regard des méthodes du droit international privé (2005); Stéphanie Francq, ‘The Scope of Secondary Community Law in the Light of the Methods of Private International Law—or the Other Way Around? (2006) 6 Yearbook of Private International Law 333; Horatia Muir Watt, ‘Private International Law’ in Jan M Smits (ed), Elgar Encyclopedia of Comparative Law (2006) 566.

Retrieved from Unilateralism (PIL) – Max-EuP 2012 on 17 April 2024.

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