European Private Law

From Max-EuP 2012

by Nils Jansen

1. Europeanizing private law

The private law of the national legal systems of Europe is based, to a large extent, on similar legal categories and basic concepts. Indeed, most modern private law concepts were coined during the time of the European common law (ius commune) on the basis of the Roman sources. Nevertheless, from the end of the 18th century onwards, private law was increasingly understood as a specifically national matter. This is not only true for states like France, where a codification had laid a new foundation for the future development of private law. In Germany, too, private law was seen as relating to a national Volksgeist (‘spirit of the people’) despite the fact that the Roman common law discussion remained vibrant until the Bürgerliches Gesetzbuch (BGB) (German civil code) came into force. During the 20th century, the national character of private law was beyond dispute all over Europe.

It is only since the 1980s that the concept of ‘European private law’ has been commonly used in legal discourse. Thus, private law has become the object of the Europeanization of the law and the political culture in Europe. Yet, the reasons and motives supporting this process are unclear. While some have made an argument, somewhat simplistically and without serious empirical support, that the Common Market requires a unification of private law, others wish to free private law intellectually from its procrustean bed of national codifications. Many lawyers are motivated by an abstract enthusiasm for Europe and by the idea of private law being an aspect of the cultural identity of Europe.

It is remarkable that the intensity of discussions regarding European private law significantly diverges between different European states. Discussion has traditionally been centred in Germany, the Netherlands and parts of Spain (especially Catalonia), additionally in Scotland and some Italian universities. Lawyers in France and in the common law nations have been more reluctant because they fear that Europeanization processes may endanger the national identity of their private laws. Conversely, the legal academia in many of the eastern and nordic European Union Member States have recently responded more positively to those developments, perhaps because fundamental legal change has been a more common experience in those countries.

It is a matter of perspective whether the Europeanization of private law is seen as the introduction of a new supra-national system of private law, or whether it is rather understood as a reconstructive continuation of the former private-law discourses of the European common law (ius commune). In any event, European private law cannot be regarded as a fully developed legal system. Instead, it is a political and academic programme. It is impossible, therefore, to use the term ‘European private law’ in a purely descriptive way; rather, every concept of European private law must be seen as an expression of a specific legal or academic policy. Accordingly, different conceptions of European private law can be found in the present discussions. While some want to construct a European private law on the basis of the acquis communautaire, ie on the European Union’s legal texts concerning private law, other approaches focus on the acquis commun, ie on the common academic tradition of the European common law (ius commune), which is the basis of the different national legal systems of Europe.

2. Acquis commun

It would be wrong to assume that the European ius commune was a time when the same law was adhered to all over Europe. Rather, the law applied by the courts was normally found in diverging local legislation and legal custom. Still, however, private law was understood as a ‘common’ law. Clearly, this concept related more to the academic discussion than to the actual rules in force. Indeed, the learned discourse of private law in Europe was based on the Roman texts of the Corpus Juris Civilis: texts that normally could only be applied subsidiarily, but nonetheless influenced the understanding of all law. All over Europe, private law was taught on the basis of Justinian’s Institutes, and it further developed on the basis of the Digest. Thus, the major textbooks on the Institutes by Vinnius or Heineccius could be used for the purpose of academic teaching all over Europe. Indeed, even local law was often explained on the basis of Justinian’s Institutes. Thus, the ius commune became the basis of a European legal discourse which not only overarched the different continental legal systems, but also formed an intellectual bridge with the English common law. Private law was thought of as independent of local and early national legislation.

In the middle of the 20th century, that discourse was revitalized; early landmarks were works such as Ernst Rabel’s Recht des Warenkaufs (1936/1958) and Reinhard Zimmermann’s Law of Obligations (1990). These books were inspired by the conviction that the basic structural questions of private law can be understood independently of the individual provisions of the positive national legal systems; indeed the abstraction from national rules may even further the understanding of private law. Today, there is again a European private law which is predicated on the learned discourse of private law. It finds its expression in a quickly increasing number of textbooks and handbooks; examples are the Ius Commune Casebooks for the Common Law of Europe, Hein Kötz’s European Contract Law (1996 (German); 1997 (English)), Filippo Ranieri’s Europäisches Obligationenrecht (1999; 3rd edn, 2009), and the handbooks on the European law of tort by Christian von Bar (1996/1999) and Cees van Dam (2006) and on the law of restitution by Peter Schlechtriem (2000/2001). The normative foundations of this acquis commun are the different national private-law systems of Europe, which are understood as together representing a common legal tradition. From a comparative perspective, this becomes apparent in the structural, evaluative and doctrinal commonalities of the national legal systems. Often, differences in detail can be explained, from a historical perspective, as resulting from accident or as diverging answers to a formerly common legal problem.

European private law has always been a ‘learned law’. As such it has long been characterized by efforts of academic systematization. Recently, this tradition gained new actuality with the increasing number of ‘Principles of European private law’: systematizing ‘restatements’ of European private law that are meant to overarch the different national systems and become a reference text for future discussions. An early benchmark were the Lando Commission’s Principles of European Contract Law, which have even gained quasi-legislative authority in some legal systems. In more recent years other European groups of academics, such as the Study Group on a European Civil Code and the European Group on Tort Law (Principles of European Tort Law), have published comparable European Principles. However, those more recent Principles have not yet gained the same legal authority as the Lando Principles.

The Study Group, incidentally, understands its Principles and especially the ‘academic’ Common Frame of Reference as a proposal for a political instrument and especially for a European civil code. Yet, it is doubtful whether such instruments would be politically desirable at the present date; from an academic point of view, drafting a code would certainly be premature.

3. Acquis communautaire

A fundamentally diverging approach has been chosen by the proponents of an acquis communautaire-conception of European private law. This approach primarily focuses on the European Union’s positive law. Since the 1980s, the European Union has been active in the field of private law; early examples are Directive 85/374 concerning liability for defective products, Directive 85/577 on contracts negotiated away from business premises, Directive 86/653 relating to self-employed commercial agents and Directive 87/102 concerning consumer credit. Since the 1990s these activities have gained momentum with instruments such as Directive 93/13 on unfair terms in consumer contracts and Directive 1999/44 on the sale of consumer goods and associated guarantees. At the same time, private-law policies may be found in directives, which—despite not being genuine private-law instruments—may be interpreted from a private-law perspective; an example is the Unfair Commercial Practices Directive 2005/29. The same is true for parts of the European Union’s primary law, such as the fundamental freedoms and competition law.

While the present acquis commun is based on the legal discourse and cannot be understood as law in the sense of a body of norms imposed by a sovereign, the European legislation and the related jurisprudence of the European Court of Justice, the two main sources of the acquis communautaire, may easily be recognized as the European Union’s private law (EU private law). However, the acquis communautaire continues to be fragmentary in character. It consists of intellectually unconnected rules on highly specific matters of law. At the same time, the substance of most of these rules is of an instrumental and regulatory nature. These new rules of the acquis communautaire do not primarily provide fair rules for balancing the conflicting interests of private parties. Rather, they aim at furthering the Common Market and at strengthening the position of consumers in order to stimulate demand in the European market (an example being the Directive on the sale of consumer goods) or to combat a distortion of competition resulting from diverging legal rules (an example being the product liability Directive). Such rules may conflict with the principles expressing the traditional corrective-justice conception of the acquis commun’s law of obligations.

From a legal practitioner’s perspective, the importance of the acquis communautaire today is difficult to overestimate. It is hardly surprising, therefore, that the acquis has become the object of comprehensive expositions. Thus, legal academics are increasingly prepared to treat the acquis, despite its fragmentary character, as a complete legal system; this becomes apparent from the first comprehensive textbooks on European private law, such as Karl Riesenhuber’s Europäisches Privatrecht (2003; 2nd edn, 2007) or Bettina Heiderhoff’s Gemeinschaftsprivatrecht (2005; 2nd edn, 2007), or from Wolfgang Wurmnest’s work on the European law of torts (Europäisches Haftungsrecht, 2003). What is more, the Research Group on the Existing EC Private Law (Acquis Group) has presented its Principles of the Existing EC Contract Law (Acquis Principles). Those ‘Principles’ have been drafted after the model of the Lando-Principles (Principles of European Contract Law). They aim at reconstructing and presenting the acquis communautaire in the form of a systematic body of rules. Yet, at present, the Aquis Principles cannot achieve an authority comparable to the quasi-legal authority of the Lando Principles. This is, inter alia, a result of the acquis communautaire’s extremely fragmentary nature. A comprehensive system of private-law cannot be formulated without generalizing individual rules. Yet generalizations of such fragmentary, intellectually unconnected norms unavoidably entail far-reaching political choices in respect of legal policy, and a self-constituted group of academics does not possess the political legitimatization which would be necessary for authoritatively making such decisions. In addition, it remains doubtful whether the acquis communautaire’s individual regulatory rules are capable of becoming the foundation of a complete system of private law.

4. Future perspectives

Neither of these two approaches provides an adequate, complete picture of European private law. This is evident in accounts that reduce European private law to the acquis commun and thus wholly ignore the European Union’s private law. However, the same is conversely true for isolated acquis communautaire conceptions, and it is not only due to the fragmentary nature of the acquis. Most regulatory provisions of the European legislator are not even comprehensible if the acquis commun is not taken into account. This is so because the private law as laid down in the national legal systems is the natural hermeneutic background for every legislator drafting its different regulatory instruments and also for the European law’s addressees who interpret the acquis communautaire’s individual provisions. Hence, the European Court of Justice, too, does not base its decisions solely on the acquis communautaire, but also on the acquis commun, ie on the general principles of private law that are commonly recognized in the different Member States’ legal systems.

European private law can be (re-)constructed but on the basis of a variety of different, equally authoritative legal sources. Besides the acquis communautaire, these are the national codifications, private law statutes and the corresponding national jurisprudence on the one hand, and international textual authorities such as the Principles of European Contract Law, the UNIDROIT Principles of International Commercial Contracts (PICC), or the CISG (sale of goods, international) on the other hand. Such a plurality of textual authorities requires specific juristic techniques that are able to reduce the complexity and incoherence of the present European private law. Thus, it will be necessary to integrate the acquis commun and the acquis communautaire intellectually into a single, unified legal system. The work relating to the project of a Common Frame of Reference for European private law is an important step in this direction.

Today, European private law can be recognized only in its basic outlines. This is especially true for areas such as property and the law of torts (law of torts/delict). Those parts of European private law are today characterized more by doctrinal and conceptual differences than by commonalities. Hence, before formulating individual rules it is necessary to lay the foundations for a common understanding overarching the different legal systems. This requires adequate conceptual instruments, which would make it possible to discuss legal problems and relevant policies independently of individual legal systems, and which could thus become the basis for innovative legal comparisons and for constructive discussions that would be necessary for reaching consensus and establishing an idea of European legal identity. The proposals of the Study Group may be taken as contributions to such a discussion. Yet, in these areas of the law, thorough individual studies analysing the legal material without a view to possible compromises required in international commissions remain indispensable. Finally, the fundamental political questions concerning European private law need to be answered satisfactorily. In view of European private law’s conceptual focus on the Common Market, this includes an answer to the question of how social justice should be understood and integrated into European private law.


Reinhard Zimmermann, ‘Konturen eines europäischen Vertragsrechts’ (1995) JZ 477; Reinhard Zimmermann, ‘Savigny’s Legacy: Legal History, Comparative Law, and the Emergence of a European Science’ (1996) 112 LQR 576; Hans-W. Micklitz, ‘Perspektiven eines europäischen Privatrechts: Ius commune praeter legem’ (1998) 6 ZEuP 253; Karl Riesenhuber, System und Prinzipien des Europäischen Privatrechts (2003); Oliver Radley-Gardner and others (eds), Fundamental Texts on European Private Law (2003); Nils Jansen, Binnenmarkt, Privatrecht und europäische Identität (2004); Study Group on Social Justice in European Private Law, ‘Social Justice in European Private Law: a Manifesto’ (2004) 10 ELJ 653; Thomas Eger and Hans-Bernhard Schäfer (eds), Ökonomische Analyse der europäischen Zivilrechtsentwicklung (2007); Research Group on the Existing EC Private Law (Acquis Group), Principles of the Existing EC Contract Law. Contract I (2007); Nils Jansen and Reinhard Zimmermann, ‘Restating the Acquis communautaire? A Critical Examination of the “Principles of the Existing EC Contract Law”’ (2008) 71 MLR 505.

Retrieved from European Private Law – Max-EuP 2012 on 15 August 2022.

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