Foreign Law (Ascertainment)

From Max-EuP 2012

by Clemens Trautmann

1. Object, terminology and relevance

If, in civil proceedings, foreign law is applicable by virtue of a rule of private international law (PIL), the procedural law of the forum determines by whom and by which means the content of that law is to be established. The general principle that a court is deemed to have knowledge of all legal elements (iura novit curia) and that the parties have to introduce the factual elements of a given case (da mihi facta, dabo tibi ius) does not or at least does not fully apply to foreign law.

The objective of the ascertainment of foreign law is to efficiently provide the court with all information necessary to apply and interpret foreign law in an equivalent way as would be done by a court in the state of origin (aliena lege artis). The European jurisdictions have chosen rather different paths towards this goal.

The terminology reflects the differing views as to the legal or factual nature of foreign law (foreign law (application)) and its consequences for the procedure of ascertainment. In common law jurisdictions the ascertainment of foreign law is referred to as proof of foreign law, owing to the presumed factual nature. French and Spanish law, although they have abandoned the fact doctrine, continue to use the terms preuve de la loi étrangère and prueba del derecho extranjero. In contrast, the German and Italian terms are, respectively, Ermittlung ausländischen Rechts (§ 293 Zivilprozessordnung) and accertamento della legge straniera (§ 14(1) Legge 218/ 1995).

The questions commonly discussed in the context of the ascertainment of foreign law include what roles and tasks the parties and the court have in establishing its content (see 2. below), which methods of establishment are available (see 3. below) and how to proceed in case the ascertainment fails (see 4. below). The relevance of these seemingly technical questions for the realization of the objectives of private international law as well as for the outcome of a litigation is not to be underestimated. Gerhard Kegel referred to the ascertainment of foreign law as the ‘secret ruler’ of private international law. Indeed, a choice of law rule can be undermined if the procedural law of the forum does not provide adequate means to establish the content of the law designated by it. Furthermore, in proceedings with an international element the final decision often hinges on the method of ascertainment or on the judicial appraisal of the information available to the court. Therefore, issues concerning the correct ascertainment of foreign law have often been reviewed on the appeal level.

2. Allocation of tasks between the court and the parties

The key question of who ascertains the applicable foreign law—the court or the parties—is generally answered in accordance with the procedural status of foreign law.

If foreign law is treated as a question of fact, as in the common law jurisdictions, the ascertainment of foreign law follows the rules of evidence. As the court is generally unable to take judicial notice of factual elements (except for notorious facts), it is the parties’ task to prove the content of foreign law. More specifically, since English law presumes that foreign law is identical with the law of the forum, the burden of proof rests on the party pleading the difference. If there is a conflict of testimony, the court must provide its own interpretation of the foreign law in light of all the evidence given. On the other hand, foreign law does not need to be proved if its content is admitted, and, if evidence is uncontradicted, the court should be reluctant to reject it (except where it is patently false).

Attributing legal quality to foreign law, however, most often corresponds with a duty of the court to establish its content ex officio. This is sometimes derived from the maxim iura novit curia, as in Germany and Belgium. Other jurisdictions specifically prescribe an ex officio ascertainment by statute, eg Italy (Art 14(1) Legge 218/95), Austria (§ 4(1) Bundesgesetz über das internationale Privatrecht) and Portugal (Art 348 no 1 Código civil). Nevertheless, it is always possible and sometimes even advisable for the parties to support the court in establishing the content of foreign law. Though there is no onus of proof, the parties may have a subsidiary responsibility for the ascertainment of foreign law, as controversial contentions heighten the necessary intensity of judicial research, whereas matching statements, passivity or delay may decrease the efforts the court is required to make.

Some jurisdictions prefer mixed, flexible models: in France and the Scandinavian states, the courts are entitled to conduct research into foreign law ex officio, but may also shift the responsibility for the ascertainment to the parties or even—especially in dispositive matters—impose a formal burden of proof. With regard to pecuniary claims, Swiss law explicitly allows the court to impose the burden of proof on the parties (Art 16(1) Bundesgesetz über das Internationale Privatrecht). Conversely, Spanish law regards the model of party proof as the standard solution, with the courts nevertheless being able to establish the relevant foreign provisions on their own motion (Art 281 Ley de Enjuiciamento Civil).

In provisional proceedings, the task allocation is usually modified towards the model of exclusive party proof. In order to obtain interim relief, the party who draws favourable conclusions from an applicable foreign law is generally required to furnish prima facie evidence as to its content.

Advocates of exclusive party proof argue that the efforts of both parties in adversarial proceedings render the best result in terms of precision and efficiency. One might object, however, that the perspective on a foreign legal practice conveyed to the judge through interest-dominated party contentions is likely to be distorted or to represent a mere amalgam of both standpoints. More importantly, a party not interested in the application of foreign law may effectively set it aside by simply failing to furnish the necessary information. Alternatively, the court may evade the burdensome application of foreign law by deeming the adduced evidence insufficient. On the other hand, in cases of a choice of law agreement in favour of a foreign law, it can rightly be said that the parties’ furnishing evidence on the chosen law is a natural consequence of the exercised party autonomy, whereas an ex officio ascertainment would lead to an externalization of costs (unless the court fees are raised in such cases). Flexible models enable the court to take the nature of the rights in dispute as well as the resources of the parties into account.

3. Means of ascertainment

Which means of ascertainment are available is predominantly determined by the national rules of civil procedure. Additionally, international conventions and European Union law may provide methods for establishing the content of foreign law. Generally, it is left to the court’s discretion which of several possible methods it chooses. Factors to be taken into account include the complexity and importance of the matter at hand, the parties’ conduct and the principle of procedural economy.

According to recent studies of the Hague Conference on PIL, approximately 15 per cent of European courts ascertain foreign law by conducting their own research into foreign legal sources; 20 per cent by means of international instruments for judicial assistance. The predominant method of ascertainment, however, is expert evidence (in many different manifestations).

a) Direct consultation of foreign sources

If ascertainment on the court’s own motion is permitted, courts can consult foreign statutes, case law and academic writings directly. This method of ascertainment has been of growing importance in the past decade. It has been promoted by the establishment of special court departments focusing on cases with international elements, where judges are often familiar with standard issues under foreign law. In addition, the accessibility of documentation on foreign law has improved. There are bilingual editions of statutes, country reports, collections of legal opinions on foreign law and—of rapidly increasing relevance—online resources such as government-run legislation websites and international legal databases which are very helpful in this respect. In many states, judges may also ask the foreign ministries or ministries of justice for assistance in obtaining material.

Under English law, however, courts are not allowed to conduct their own research into foreign law and may take notice of documentation on foreign law only as part of expert evidence. One practically irrelevant exception where documentary proof is admitted is contained in s 4(2) Civil Evidence Act 1972 that enables the use of an earlier English decision on foreign law. Recent jurisprudence shows, however, that there is certain willingness on the part of English judges to provide legal input and consult foreign sources as part of their assessment of the adduced evidence.

b) Assistance of experts

The content of foreign law is very commonly established with the assistance of experts. However, there is huge variance as to the relevant procedural rules as well as to the role, background and qualification of such experts. In particular, one can distinguish between whether the expert is party-appointed or court-appointed and whether the information is delivered in an oral or written form.

In Austria, Germany, the Netherlands and Switzerland (and to a lesser extent in Italy), the experts are appointed by the court. Their opinions, which are usually submitted in writing, have considerable weight for the judicial decision; therefore the procedural framework is similar to the rules of evidence. In particular, the parties have the right to question the experts, which may necessitate their personal appearance in court. Usually, those experts reside in the country where the litigation takes place and are employed at institutes specializing in comparative law such as the Max Planck Institute for Comparative and International Private Law (Hamburg), the Swiss Institute of Comparative Law (Lausanne), the Internationaal Juridisch Instituut (The Hague) or in university departments.

Written expert opinions are recognized as documentary evidence of foreign law in France (certificat de coutume), Spain (certificado de ley) and Italy (testimonianza sul diritto straniero). Such opinions are mostly commissioned by one of the parties, though, and are therefore subject to special scrutiny by the courts. They are typically prepared by consular authorities or foreign legal practitioners or academics.

Under English procedural law, foreign law is proved by expert evidence, ie by witnesses who are suitably qualified on account of their knowledge or experience (s 4(1) Civil Evidence Act 1972). Traditionally, oral evidence is adduced and, if necessary, the opposing party-appointed experts are cross-examined in court. The reformed English law of civil procedure, though, requires evidence in a written report unless the court directs otherwise (r 35.5(1) Civil Procedure Rules (CPR)). Additionally, it underscores that the expert’s duty to help the court on matters within their expertise overrides instructions by the parties (r 35.3 CPR). Another novelty is the possibility for the court to direct that evidence be given by a single joint expert (r 36.7 CPR). In these respects, English law is somewhat convergent with continental ascertainment methods. It is to be seen, however, whether these options will be accepted in practice. Since cases turning on issues of foreign law are often complex and strongly contested, it is conceivable that courts will continue to prefer the traditional adversarial approach.

c) International instruments

Among the international instruments for the ascertainment of foreign law, the European Convention on Information on Foreign Law of 1968 (London Convention), which was adopted under the auspices of the Council of Europe, is by far the most relevant. Besides this pan-European instrument with over 40 contracting European States (to which Mexico and Costa Rica also acceded), various bilateral conventions on international legal information exist.

The London Convention provides a system through which national courts can submit abstract questions on the laws and procedures of other contracting states (Art 1). Via national transmitting and receiving agencies (typically, ministries of justice or foreign affairs), the requests are conveyed to foreign authorities or legal counsels that draw up the replies free of charge (Arts 2–6, 15). The non-binding replies consist of the statutes, decisions and extracts from doctrinal works pertinent to the case at hand, which may be accompanied by additional comments (Arts 7, 8). As to the practical value of the London Convention, there is no clear assessment. The last survey, prepared by the Hague Conference on Private International Law with 2006 data, suggests there are up to 200 requests per year. Although the process is slightly impeded by the need for translations (the request as well as the reply are to be issued in the language of the requested state), the average handling time is only two months.

For some special subject matters, direct communication between judges of different countries on questions of foreign law is possible, most notably in cases of international child abduction (child law (international)). Under the Hague Convention on the Civil Aspects of International Child Abduction, a network of liaison judges has been established. Another special instrument is the 1859 British Law Ascertainment Act, which allows English courts to refer questions regarding the law of a Commonwealth state to the supreme court of the relevant country.

d) European Judicial Network

For intra-Union cases, information on the applicable foreign law can be obtained through the European Judicial Network in Civil and Commercial Matters which was established by the Council under Decision 2001/470/EC of 28 May 2001 and recently amended by Decision 568/ 2009/EC of the European Parliament and of the Council (Council and the European Council) of 18 June 2009. This reform must be seen as a supplement to the EU legislation in the field of private international law (PIL) as it tries to facilitate the ascertainment process whenever the law of another Member State is applicable by virtue of conflicts rules in an EU instrument or international convention (recital 8 Decision 568/ 2009/EC). Article 3(2)(b) allows courts as well as other authorities to apply to the network for information on the content of the applicable law of another Member State. Thus, the network enables direct judicial communication (established through contact points) on matters of foreign law. As the network is more flexible, it may replace the London Convention in intra-Union cases, though its existence and potential are still relatively unknown in court practice.

4. Failure to ascertain the applicable foreign law

There is no clear benchmark for determining at what stage the content of foreign law is sufficiently ascertained. The standards applied in the European jurisdictions vary considerably (even within the jurisprudence of a given Member State). Sometimes a judge may be satisfied with a mere reproduction of the relevant foreign statute, while other courts require detailed information as to its interpretation and the foreign legal practice. If the ascertainment of foreign law follows the rules on evidence, a subjective standard will be applied and the decision is left to the autonomous appraisal of the judge. Occasionally, it can be observed that courts will jump to the conclusion that the foreign law cannot be ascertained. Indeed, it may sometimes be difficult to differentiate in what cases the provided material does not convey a clear picture of the legal framework in the country of origin (descriptive problem) and in what situations a given rule needs to be interpreted in order to be applied to the case at hand (interpretative problem).

If the law designated by the relevant choice of law rule cannot be ascertained, the European jurisdictions provide for the application of a subsidiary law. This approach is even followed in jurisdictions adhering to the view that foreign law needs to be pleaded and proved like a question of fact, although one might logically assume that a non liquet should consequently result in the dismissal of the claim or the defence relying on foreign law. Only in provisional proceedings does the failure to substantiate the content of the applicable foreign law regularly lead to the dismissal of the application.

Which law is to be applied as a subsidiary solution has been a much debated question. For the sake of practicability, most European jurisdictions apply the substantive law of the forum, either with statutory support as in Austria (§ 4(2) Bundesgesetz über das internationale Privatrecht) or Belgium (Art 15 § 2 Code de droit international privé) or else as a default solution established praeter legem by jurisprudence as in Germany, France, Spain and—within a different framework—England. French legal commentators justify this solution with the vocation générale of forum law. Under English law, it is backed by the presumption of similarity (although its plausibility has been questioned of late): in case the proof fails, it is assumed that foreign law is the same as English law.

By contrast, Italian and Portuguese law stipulate the application of the next available law that is declared applicable by an alternative or subsidiary choice of law rule; only in the absence of such law does the lex fori apply (Art 14(2) Legge 218/95; Art 23(2) Código civil). This approach has received widespread academic support as it safeguards the objectives of private international law, especially the international harmony of judgments, to the largest possible extent. Other academic proposals favour the application of a closely related law stemming from the same legal tradition or else from uniform law or general principles of law.

5. Tendencies

Recent proposals have focused on facilitating the process of ascertaining foreign law by means of intensified judicial cooperation and electronic media. Even if these proposals demonstrate considerable potential for improvement of the status quo, the ascertainment of foreign law will remain burdensome and a weak spot with regard to the practical realization of private international law objectives and decisional harmony.

The Hague Conference on Private International Law conducted preparatory work for a convention on the international information on foreign law, which is intended to operate on a global scale and make use of digital communication media (as opposed to the London Convention and existing regional or bilateral instruments). Although the efforts have recently been reduced and the Hague Conference is now focusing on facilitating access to foreign law in the context of the existing Hague conventions, this item will be retained on the organization’s agenda.

As for intra-Union cases, it will be interesting to observe the acceptance and performance of the European Judicial Network in Civil and Commercial Matters after its recent reform (effective from 1 January 2011). As the Europeanization of private international law progresses, it is conceivable that the network will be further developed to become the standard information instrument wherever the law of another Member State is applicable. In academic literature, even more radical suggestions have been made which would operate within the framework of the European Area of Freedom, Security and Justice, eg procedures for binding or non-binding preliminary rulings handed down by courts whose forum law is applicable in a given case.

There is a tendency to open international instruments for the ascertainment of foreign law to other legal professions and to make information on foreign law publicly available to citizens in their respective language. This trend could be observed in the deliberations to the Hague Conference and has been realized in the European Judicial Network: professional associations representing lawyers, notaries, bailiffs and other legal practitioners dealing with judicial cooperation in civil and commercial matters will also be able to participate in the determination process (Art 2(1)(e) Decision 568/2009/EC). One of the network’s main tasks is the implementation of an information system for the public in cross-border litigation.

The Europeanization of private international law will likely impact the national rules on ascertainment of foreign law in the Member States. The effect of these rules for the practical application of a foreign law designated by an EU conflicts rule will also be covered by the study provided for in Art 30 Rome II Regulation (foreign law (application)). Under the EU regulations, it is doubtful whether the complete task of establishing the content of foreign law can solely be imposed on the parties, for this approach involves the risk that the ascertainment fails due to a lack of resources and that European choice of law rules are thus rendered ineffective. The jurisprudence of the European Court of Justice (ECJ) instead suggests that national courts have to intervene and exhaust all instruments available to them ex officio if the establishment of a factor relevant for the application of Union law otherwise fails (ECJ Case 526/04 – Laboratoires Boiron, [2006] ECR 7529). Other issues are the standard of sufficient proof and the effects of a failure to ascertain foreign law, both of which might have to be harmonized in order to secure the chief legislative goal of the European regulations, namely the foreseeable application of the same national law regardless of the forum.


Richard Fentiman, Foreign Law in English Courts (1998); Oliver Remien, ‘Iura novit curia und die Ermittlung fremden Rechts im europäischen Rechtsraum der Artt 61ff EGV—für ein neues Vorabentscheidungsverfahren bei mitgliedstaatlichen Gerichten’ in Jürgen Basedow and others (eds), ‘Aufbruch nach Europa’ (2001) 75 Jahre Max-Planck-Institut für Privatrecht 617; Maarit Jänterä-Jareborg, ‘Foreign Law in National Courts’ (2003) 304 Recueil des Cours 182; Sofie Geeroms, Foreign Law in Civil Litigation (2004); Lord Collins and others (eds), Dicey, Morris and Collins on the Conflict of Laws, vol I (14th edn, 2006) ch 9 (Proof of Foreign Law); Hague Conference on Private International Law: Report on judicial communications in relation to international child protection (Prel Doc No 8 of October 2006); Feasibility study on the treatment of foreign law (Prel Doc No 21A of March 2007); Summary of the responses to the questionnaire (Prel Doc No 9A/B of March 2008); Accessing the content of foreign law, Report of the meeting of experts on global co-operation on the provision of online legal information on national laws (Prel Doc No 11B of March 2009); Clemens Trautmann, Europäisches Kollisionsrecht und ausländisches Recht im nationalen Zivilverfahren (2011).

Retrieved from Foreign Law (Ascertainment) – Max-EuP 2012 on 15 June 2024.

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