1. Does Foreign Law Really Matter in Domestic Adjudication?
The practice of making reference to foreign law by courts is one of the most widely discussed topics in contemporary legal scholarship. Although justifying a legal decision via a comparison between domestic law and foreign law has become a worldwide phenomenon, this practice continues to give rise to a number of related issues: the legitimacy of using foreign legal materials by domestic courts, the alleged de facto authority acquired by foreign law and its consequence on the structure of domestic legal orders, and the political significance of comparative reasoning with regard to the function of courts in the global scenario.Footnote 1
Three different points of view toward these issues can be currently identified in the debate. According to some scholars, when performed in the courtroom comparative reasoning appears as a cosmetic exercise of erudition which does not deserve any serious consideration. From this perspective, making reference to foreign law is a rhetorical device which has been used by judges for at least two centuries and has no appreciable impact on case law.Footnote 2 Other critics regard the current use of foreign law by courts as a pernicious habit which undermines the authority of domestic law without producing any positive effect on adjudication. They believe that courts should be prohibited or at least discouraged from relying on foreign legal materials when rendering decisions since this would preserve the stability and integrity of their own legal order.Footnote 3 On the contrary, others see this phenomenon in a positive light as it represents a valuable change in the general understanding of law by judges, a change that leads domestic courts to enter into dialogue with courts located in a different jurisdiction and to pursue forms of cross-fertilization and harmonization between legal orders. In this perspective, comparative reasoning is seen as an argumentative tool through which courts establish informal links between different legal orders, share information and adjudication standards, resolve potential conflicts between competing judicial regimes, or build up a systematic body of legal principles common to all jurisdictions.Footnote 4
In relation to this, Fred Schauer has claimed that foreign law is not binding but has become authoritative, thereby changing the nature of law in the contemporary legal scenario: “The various contemporary controversies about citation practice [of foreign law] turn out to be controversies about authority, and as a result they are controversies about the nature of law itself.”Footnote 5 According to Schauer, foreign law is at present treated as a set of content-independent reasons for judicial decision; it is not simply rhetorical support for adjudication. Obviously, the authority thereby acquired by foreign law is merely optional and not mandatory. Nevertheless, considering foreign law as authoritative could progressively affect the rule of recognition of a given legal order, i.e., the practice through which judges and other legal officials identify the sources of law. From this point of view, “citation practice reflects something deeper: a change in what counts as a legal argument. And what counts as a legal argument—as opposed to a moral, religious, economic, or political one—is the principal component in determining just what law is.”Footnote 6
The idea underlying this article is that the theory of legal argumentation could help us to elucidate the characteristics and functions of legal comparison in judicial decision-making and to determine whether Schauer’s claim is true, that is, whether current uses of foreign law in legal adjudication give any evidence of a change in the nature of law. To this purpose, I shall provide a theoretical framework for distinguishing various forms of comparative reasoning which depend on implicit assumptions that often remain buried in judicial discourse. By clarifying these assumptions, and the structure of comparative reasoning in general, I will outline a systematic picture of this argumentative practice, a picture that shows under what conditions referring to foreign law in legal adjudication is justified on its own grounds. Thus, what follows can be considered a short guide for a consistent use of comparative reasoning by courts.
The article proceeds as follows. I will start by considering the standard account of this argumentative technique provided by argumentation theory (2.). I will then show that the label “comparative reasoning” refers to an argumentative toolkit which includes different standards of legal justification (3.). Distinguishing between different kinds of comparative reasoning will help to make explicit their inferential structure and implicit premises, and to determine how each type of comparative argument affects judicial decision-making (4. and 5.). This analysis will reveal the argumentative constraints (if any) placed on courts when making reference to foreign law, and help determine whether or not this phenomenon is changing what counts as law in contemporary legal systems (6.).
2. Comparative Reasoning and Systemic Argumentation
Traditionally, comparative reasoning is classified as a systemic argument in law. More precisely, it is a kind of ab exemplo reasoning, also known as argumentum ex auctoritate.Footnote 7 Arguments from authority justify a judicial decision based on one or more previous decisions provided by the same or other courts. These arguments are usually considered as a sort of systemic argumentation because they are connected to the ideal of the Rule of Law, which is considered as a fundamental virtue of legal systems: a legal system realizes this ideal in so far as it guarantees equality and legal predictability, regardless of the parties involved in a legal dispute or the judge who is deciding it. As Neil MacCormick put it, “faithfulness to the Rule of Law calls for avoiding any frivolous variation in the pattern of decision-making from one judge or court to another.”Footnote 8 And avoiding such variations requires the consistency and coherence of legal systems over time. However, the difference between comparative arguments and other arguments from authority is that the previous ruling to be considered in the justification process is provided by authorities operating in a different legal order than the court’s own. The standard form of comparative arguments can be outlined as follows: a judicial decision in legal order LO1 is justified if it is coherent with the way in which cases that are relevantly similar to the one to be decided have been ruled in legal order LOx.
This argument can also be described as an inference whose conclusion lays down an interpretive rule which a court may apply when determining the content of a domestic legal provision (i.e., the norm expressed by an authoritative legal text as a result of legal adjudication):
(1) Ascribe to legal provision P1 belonging to legal order LO1 the content N that is coherent with content Nx of provision Px belonging to legal order LOx/
(2) Nx is relevant to the cases covered by P1/
(3) P1 admits contents N1, N2, N3…Nn/
(4) N1 is coherent with Nx//
(5) Ascribe content N1 to P1.
Like every other systemic argument in law, this argumentative standard follows the intuition that the content of a legal provision is not atomic but rather holistic as it depends on the system of norms it belongs to. In short, legal contents depend on context: determining the norm expressed by an authoritative legal text is a holistic endeavor based upon connections between norms which are seen as a coherent systemic whole. But what does “coherence” mean here? This term refers to a relational property of norms that identifies the structure of a normative system and determines its membership conditions.Footnote 9 In this respect, norm N1 and norm Nx are said to be coherent if N1 and Nx do not provide incompatible legal consequences for the same case (consistency), or N1 is a means to realize the end stated by Nx (teleological coherence), or N1 and Nx specify the content of the same legal principle or value (axiological coherence).
Such a systemic whole does not, however, necessarily limit its contents to a given legal order, i.e., the set of legal norms that exist or are valid in a certain institutional organization such as a State or a supra-national regime.Footnote 10 Although the expressions “system of legal norms” and “legal order” are mostly used as synonyms in legal discourse, it is not so in argumentative discourse when a systemic argument is invoked by a court to justify its ruling.Footnote 11 In this particular context, the system of legal norms a court appeals to may be composed of the same elements that make up a legal order, but this is not always the case. It can be constituted by a sub-set of norms belonging to a legal order, by a single legal document, or it may include components that are not incorporated in the legal order in which the court operates, such as foreign or international laws, legal doctrine, conceptual distinction elaborated by legal scholars, etc. Consequently, in the argumentative practice of courts norms belonging to different legal orders can be considered members of the same systemic set of norms, whereas norms belonging to the same legal order can be seen as members of different systemic sets. In the context of legal argumentation, therefore, systems of legal norms are intellectual constructions elaborated by judges to pursue certain goals or protect certain principles or values.
As far as comparative reasoning is concerned, the system of legal norms a court relies on is composed of norms belonging to different legal orders: usually, one or more foreign norms (source) and one domestic norm (target). This systemic set is tailored to fit a judicial outcome whose legal effects are limited to the target legal order, but at the same time such effects are harmonized with those of the norms belonging to the source legal order.
3. Types of Comparative Reasoning
If we look at judicial practice in general, however, it is easy to see that comparative reasoning is used in many different ways. The expression “comparative reasoning” actually refers to a large family of argumentative tools which can be used in the justification of different rulings of the same case in different legal contexts and situations—such as between one State’s law and a separate State’s law.
The different kinds of comparative reasoning can be identified by reconstructing their standard argumentative form. The argumentative forms I present here simply explain how comparative reasoning is, in fact, used by courts: they are tools for a fine-grained analysis of the ways in which judges uphold their rulings.Footnote 12 Furthermore, comparative arguments, like any other form of judicial reasoning, can play different roles in the justification of a judicial decision. We will examine later whether courts consider them necessary or sufficient for justifying the decision of a legal dispute, or if comparative arguments are merely persuasive. For the time being, I will leave this question open and focus on the different uses of this argumentative technique.
First of all, comparative reasoning is used by courts as an interpretive or integrative argument.Footnote 13 In the interpretive case, comparing foreign and domestic law is of help in justifying a way of understanding the content being ascribed to a domestic legal provision. In the integrative case, comparative reasoning is used to fill a gap in the law: it is assumed that the case is not covered by domestic law and can therefore be settled by foreign law. Let us examine more closely the two versions of the argument in question.
3.1. Comparative Reasoning as Interpretive Argument
When used as an interpretive argument, comparative reasoning can serve two main purposes, depending on whether the coherence relation the argument is based upon is considered in a positive or negative way.Footnote 14 A positive coherence relation licenses the interpreter to take N1 and Nx as items belonging to the same systemic set of norms although they are members of different legal orders. This is the case of the standard argumentative form described above:
(A1) N1 of LO1 is justified if N1 is coherent with Nx of LOx, Nx being relevant to the cases covered by N1.
In other words, the interpretive rules provided by this argument requires the court to interpret a given domestic provision so that its content is coherent with a foreign legal norm. In Atkins v. Virginia the U.S. Supreme Court held that the Eighth Amendment of the Constitution, which prohibited “cruel and unusual punishments”, prohibits death sentences for criminal defendants who are mentally retarded. In justifying its interpretation of the term “cruel”, the court claimed that “within the world community, the imposition of the death penalty for crimes committed by mentally retarded offenders is overwhelmingly disapproved.” Although this factor is “by no means dispositive”, its “consistency with the legislative evidence lends further support to our [interpretive] conclusion.”Footnote 15 In this sense, the domestic constitutional norm and the corresponding foreign norms were considered by the court as belonging to the same systemic set, thereby justifying the regulation of the case adopted in another jurisdiction.
When used as a negative relation, on the other hand, the purpose of the coherence relation is to differentiate two systemic sets of norms in which the same legal term or phrase expresses different contents. In this case, comparative reasoning has the following form:
(A2) N1 of LO1 is justified if N1 is not coherent with Nx of LOx, Nx being relevant to the cases covered by N1.
Comparative reasoning shows here that a foreign legal solution does not fit the domestic legal context and has to be rejected: an interpretation of the domestic legal provision is justified when it is incompatible with the interpretation of the corresponding foreign legal provision.Footnote 16 Thus, if the domestic provision P1 admits contents N1, N2…Nn, and N1 is incompatible with the content Nx of the legal text Px which is being compared, whereas N2…Nn are not so, then N1 is justified. Comparative reasoning is used, in this sense, to distinguish two systemic sets of norms—which may correspond to two legal orders—that encompass different legal concepts and structure, or divergent cultural features, social needs, ends or values. In Regina v. Keegstra, the Supreme Court of Canada was asked whether communications which wilfully promoted hatred against Jews are protected by section 1 of the Canadian Charter of Rights and Freedoms, according to which the limitation of rights or freedoms is only permitted if it “can be demonstrably justified in a free and democratic society.” The court claimed, among other things, that the experience of the United States in protecting free expression might be useful in the interpretation of this constitutional provision: “A collection of fundamental rights has been constitutionally protected for over two hundred years [in the United States]. The resulting practical and theoretical experience is immense, and should not be overlooked by Canadian courts.” However, the Supreme Court of Canada claimed that American constitutional law should be examined “with a critical eye”: “Canada and the United States are not alike in every way, nor have the documents entrenching human rights in our two countries arisen in the same context. It is only common sense to recognize that, just as similarities will justify borrowing from the American experience, differences may require that Canada’s constitutional vision depart from that endorsed in the United States.”Footnote 17 Consequently, the Court rejected the First Amendment jurisprudence of the U.S. Supreme Court, as far as hate propaganda legislation was concerned, and interpreted section 1 of the Canadian Charter as justifying legislative incursions placed upon free expression even where there is no clear and imminent danger of breach of peace.Footnote 18 To sum up, the domestic constitutional norm and the corresponding U.S. norm were taken to belong to different systemic sets based upon different principles and values, thereby justifying a different regulation of similar cases. It has to be noted, however, that the negative comparative argument is not conclusive: it identifies the interpretive outcomes which cannot be accepted by the court but it does not establish the norm that is to be applied to the case. Other argumentative tools are needed to do this.Footnote 19
3.2. Comparative Reasoning as Integrative Argument
As I have outlined above, courts make use of foreign reference not only to justify their judgments or decisions with regard to the interpretation of a domestic legal provision but also to fill a gap in the law. If a case is not regulated by the law known to a court, comparative reasoning helps courts to find a norm originating in a different legal order that can be applied to it. In these circumstances, the standard form of the argument is the following: if case C is not regulated by LO1 but it is regulated by Nx of LOx, Nx being applicable in LO1, then the case should be regulated by Nx. Therefore,
(A3) Nx of LOx is justified in LO1 if Nx is applicable in LO1 and rules a case that is not regulated by any N of LO1.
This version of the comparative argument is not to be confused with analogical reasoning. Case C should not be regulated according to Nx merely because C has a relevant property in common with the set of cases covered by Nx. This argument simply justifies the application of a norm originating in a different legal order on the basis of a rule of reference (renvoir) that authorizes the judge to resort to external sources of law.Footnote 20 Comparative reasoning is used here, in particular, to determine which of the foreign norms that are applicable in the domestic legal order is to be applied.
This kind of comparative reasoning is used by courts operating in a supra-national scenario, such as EU Courts: the norms compared belong here to legal orders with vertically integrated relationships and comparative reasoning shows how these legal regimes are mutually interlocked. According to art. 19 TUE (ex-art. 164 of the EC Treaty), for instance, EU courts have “to ensure that in the interpretation and the application of this Treaty the law is observed” [my emphasis]. But what does “the law” mean in this context? Art. 19 TUE in fact empowers EU Courts to resort to comparative reasoning to fill a gap in EU law.Footnote 21 In Factortame III the ECJ held that “[s]ince the Treaty contains no provision expressly and specifically governing the consequences of breaches of Community law by Member States, it is for the Court, in pursuance of the task conferred on it by Article 164 of the Treaty […], to rule on such a question […] by reference to the fundamental principles of the Community legal system and, where necessary, general principles common to the legal systems of the Member States.”Footnote 22 According to the ECJ, therefore, the term “law” in art. 164 refers to legal comparison: in order to fill a gap in EU law, EU courts are requested to compare different legal orders and single out the common principles thereof. In this case, comparative reasoning becomes a necessary argumentative tool when Community law does not provide an answer to a legal question.Footnote 23 The judgment will “tend to be the result of ‘cross’ contributions of different legal systems.”Footnote 24 The origin of these contributions is not always explicitly declared by the ECJ. As a matter of fact, the ECJ usually applies one of the norms of one of the Member States and justifies this practice through comparative reasoning. Thus, a norm belonging to a source legal order is applied by a court operating in the target legal order.Footnote 25
4. The Cherry-picking Problem
The interpretive and integrative versions of comparative reasoning in law just discussed face the same problems in legal adjudication. First of all, courts have to choose which foreign legal orders and provisions are relevant for comparative reasoning and worth being considered in judicial decision-making. This is the so-called “cherry-picking problem.” There seems to be no general criteria for selecting the norms to be compared: courts feel free to pick and choose, from decisions and other legal materials around the world, those which they prefer as justification tools for their ruling, and “to ignore decisions that are to the contrary.”Footnote 26 In Lawrence and Tyron v. Texas, the U.S. Supreme Court was asked to determine whether the Constitution’s Fourteenth Amendment confers a fundamental right upon homosexuals to engage in consensual sodomy. In interpreting this constitutional provision, the court considered the view of Western civilized societies as a relevant subject for interpretive comparison.Footnote 27 In Naz v. Government, a constitutional case dealing with the same problem,Footnote 28 the Indian Supreme Court made an exceptionally wide use of comparative reasoning. However, it did not only take into consideration Western adjudication but also decisions made in Fiji, Hong Kong and Nepal, in order to remind the cynic, as a commentator pointed out, that “gay rights aren’t some luxurious Western construct.”Footnote 29 This seems to show, as Justice Scalia has pointed out, that “to invoke alien law when it agrees with one’s own thinking, and ignore it otherwise, is not reasoned decision-making, but sophistry.”Footnote 30 Accordingly, Justice Roberts noted that “in foreign law you can find anything you want”: looking at foreign law for support “actually expands the discretion of the judge. It allows the judge to incorporate his or her own personal preference [and] cloak them with the authority of precedent.”Footnote 31
From a theoretical point of view, however, it does not suffice to say that comparative reasoning depends on a discretionary choice by courts. Since this kind of reasoning is widely used and accepted as a means of legal justification, the question is: under what conditions, if any, is picking a certain alien norm for comparative purposes justified? Are there no reasons at all that give grounds for choosing a particular regulation or legal order for comparison? The argument we have been considering so far has no answer to this question, as comparative reasoning cannot provide its own foundation. It has to be noted, however, that courts sometimes justify their choice by means of other legal arguments: they resort to a different argumentative standard to give grounds for comparing a certain foreign regulation with the domestic one. But it is not always so: in some cases, the reasons for picking a certain foreign norm remain implicit, with the result that comparative reasoning appears groundless. Yet what is implicit in judicial discourse can be reconstructed counterfactually.Footnote 32 When a court provides no reasons for giving preference to a certain foreign norm or legal order, our question becomes: if that court had been asked to justify its use of foreign law in adjudication, what reasons could the court have provided in the light of the standards of legal justification accepted in the correspondent legal order? The answer to this question does not describe actual judicial reasoning but how a court could provide an adequate and complete justification of its argumentative choices in the considered legal context.
If one adopts this kind of analysis, it is easy to see that the justification process follows two steps. In order to determine which foreign norm is to be compared to their own, courts first look for a foreign norm or legal order that is relevantly similar (in the case of a positive coherence relation) or relevantly dissimilar (in the case of a negative coherence relation) to the domestic norm or order. On the basis of this similarity or dissimilarity, two norms belonging to different legal orders appear comparable, and the choice of the alien regulation is hence justified for comparative purposes.Footnote 33 The form of this argumentative step is as follows:
(B1) If Nx of LOx is relevantly similar to N1 of LO1, then comparing N1 with Nx is justified;
or
(B2) If N>x of LOx is relevantly dissimilar to N1 of LO1, then comparing N1 with Nx is justified.
(B1) justifies a positive use of comparative reasoning whereas (B2) justifies a negative use of this argument. Now, this first step simply provides a reason for distinguishing between comparable and not comparable legal norms. Other argumentative tools are needed to justify the choice of a certain alien norm or legal order among those that are comparable with domestic law. As a matter of fact, courts may resort to different arguments in order to select which alien norm or legal order are worth considering for comparative purposes. More precisely, courts may justify their choice as one determined by law through arguments from purpose, arguments from principles, arguments from consequences and historic-genetic arguments. A closer look at these arguments shows how this occurs:
(C1) Argument from purpose: The preference for alien norm Nx depends on the social or political ends pursued by the system of norms in which Nx is to be included. When Nx is considered a suitable means to achieve the goals of the legal system, then choosing Nx for comparative purposes is considered to be appropriate. In the ECJ’s adjudication, for instance, the choice of the State norm to be used to fill a gap in EU law depends on which legal solution better suits EU legal purposes, namely European integration in a “Community based on the rule of law.”Footnote 34 In other words, if a certain norm of a Member State is seen as a suitable means to realize the ideal of the rule of law in the European community, then this norm can be considered as a part of the EU legal system and used to fill a gap in EU law.
(C2) Argument from principle: The preference for alien norm Nx depends on the legal principles characterizing the legal order in which Nx will be applied. If Nx is coherent with these principles, in the sense that it allows courts to better protect them, the use of Nx in comparative reasoning is justified. In Atkins v. Virginia and Roper v. Simmons, for example, the U.S. Supreme Courts took into consideration only Western legal orders, and the ruling of the ECtHR in particular, because they share with the U.S. federal order the same sets of fundamental rights and principles.Footnote 35 According to the Supreme Court, this common basis justifies legal comparison and the actual use of foreign law in the interpretation of the U.S. Constitution.
(C3) Argument from consequences: The preference for alien norm Nx depends on the social consequences it has triggered in its original legal context. If these consequences are considered relevant by judges in their own social context, then considering this norm as a subject of comparison is justified. In Washington v. Glucksberg, for example, the U.S. Supreme Court looked to Dutch experience with physician-assisted suicide to establish whether recognizing this practice as a fundamental right might encourage related forms of euthanasia or undermine medical ethics.Footnote 36 In such cases, comparative reasoning is used to settle factual disputes that influence the justification of a judicial decision.Footnote 37 Courts assume that they can learn from the experience of other courts and legal orders in the regulation of a certain social issue, since foreign law provides “a road map of consequences that are likely to follow.”Footnote 38
(C4) Historical-genetic argument: The preference for alien norm Nx depends on its origin and development over time. If the foreign legal order LOx originates in the domestic legal order, or is a part of the same family or shares the same history, then it is justified to use Nx of LOx for comparative purposes. In Mohamed v. President of the Republic, the Constitutional Court of South Africa was called upon to decide whether the deportation of an illegal immigrant to the United States, where he was accused of international terrorism, was in breach of the South African Bill of Rights, given that the immigrant could be convicted to death in the U.S. In order to deal with this issue, the Court extensively examined the adjudication of Commonwealth countries with regard to similar cases, assuming that the experience of those legal orders that share their historical inheritance with the domestic one is of great significance in constitutional interpretation.Footnote 39 In this sense, the development of a legal order over time is considered a suitable basis for legal comparison.
In the light of the foregoing analysis, it is apparent that the so-called “comparative reasoning” is a complex justification process including varying inferential steps. Firstly, this argument is used either to justify a judicial decision or to show that a decision is not justified. Furthermore, it serves to justify the interpretation of a legal provision or to fill a gap in the law. By using comparative reasoning to achieve one of these purposes, courts commit themselves to further argumentative moves, which can justify the selection of those alien norms that are suitable for legal comparison. Obviously, this does not remove the fact that comparative reasoning involves judicial discretion: this argumentative technique can be used to justify different interpretations of the same legal text and different solutions to the same judicial dispute. Nevertheless, making reference to foreign law puts a number of argumentative constraints on judicial choices: these constraints are expressed, firstly, by the rule of inference characterizing each version of the comparative argument and, secondly, by the interpretive rules or standards that justify its premises. These rules and standards provide what Michael Bratman calls “framework reasons” for decision-making: they frame and shape the justification process by fixing argumentative starting points, by filtering out some options from courts’ deliberation and selecting the admissible ones.Footnote 40 Therefore, by analysing the inferential structure of comparative reasoning one may identify the appropriate and inappropriate uses of it: referring to foreign law will be inappropriate when it makes the judicial outcome inconsistent with its own premises.
This is only one part of the story, however. From the perspective of legal argumentation, the question becomes: what licenses a court to follow one of the argumentative routes outlined here rather than another? Under what conditions, for instance, are historic-genetic considerations preferable to the assessment of social consequences, or to compliance with legal principles, in order to justify the choice of a certain foreign norm for comparative purposes? What further argumentative commitment do courts undertake in this respect, and under what conditions could their choice be ultimately justified?
5. Normative Theories of Comparative Law
If we look at legal practice, it is apparent that the relationship between comparative reasoning and other forms of legal reasoning depends on some general assumptions regarding the nature and purpose of comparative law. These assumptions work as “meta-rules of legal argumentation”Footnote 41 in judicial discourse: they identify which of the argumentative paths described above is preferable. The theories of legal comparison developed by legal scholars over the last few decades play an interesting role in this respect, in spite of the fact that comparative law is sometimes seen as exhibiting “a lack of methodological reflection and theoretical foundation.”Footnote 42 These theories, or some fragments of them, are actually used by courts as preferential rules to select which kind of comparative argument is to be favored. I am not claiming here that courts engage in theoretical reflections concerning the characteristics and purpose of legal comparison. When comparing norms belonging to different legal orders, judges do not ask themselves whether they must look at them in the same way as a foreign lawyer sees his or her own law, or whether they should look at foreign law from their own domestic point of view. Nor are judges interested in discussing epistemic issues concerning the accessibility of foreign legal experiences and practices.Footnote 43 Courts however often use claims borrowed from the theoretical debate on these issues or tacitly assume them when considering foreign legal materials. When included in judicial discourse, these claims outline a set of “judicial theories” of comparative law, very broadly conceived, that provide the foundation of comparative reasoning: they state how legal comparison should be carried out by courts. In this respect, three main normative standpoints can be identified: a universalist, a genetic and a reflexive theory of legal comparison. These can be roughly outlined as follows:
(D1) Universalist theories of comparative law. According to this view, the function of the law is to respond to social problems or protect common principles, assuming that all societies ruled by law (or a significant portion of them) face the same social problems or share the same basic principles. Thus, the universalist theory may have either a functional foundation, which relies upon common features of social agency,Footnote 44 or a cosmopolitan basis, provided by a set of principles or values that are common to all mankind.Footnote 45 In both cases, this theoretical stance allows courts to identify cross-cultural and institutional links between different legal orders that serve as a basis for comparison. Moreover, this approach makes room for the assessment of alternative regulations of a social issue or for the evaluation of different normative means used to pursue a moral or political aim.
This broad view on the nature of law and the function of comparative law justifies both teleological-comparative reasoning (C1) and comparative reasoning based upon principles (C2). In the first case, judges adopt a functional approach to legal comparison in the decision-making process; in the second case, they embrace a cosmopolitan, substantive approach. Understanding legal norms as responses to universal social problems, or as a means to protect common principles and values, actually makes it possible to identify which foreign legal order must be compared with the domestic one and to establish the most suitable solution to a legal issue. On this normative basis, legal decisions anchored to comparative reasoning are typically seen as a way to reform domestic law and to create a global uniform law: legal adjudication is seen as an activity whose moral and political relevance transcends national boundaries.Footnote 46
(D2) Genetic theory of comparative law. According to this view, comparative law simply shows how legal orders develop over time. Legal orders often originate from a common social and cultural basis but then differentiate from one another as a consequence of their continuing evolution in a given context. This common source can be seen as a substantial basis for comparison: if one legal order (or one of its norms) derives from another legal order, then comparison is possible and may give useful information about the expected evolution of a given regulation and its practical consequences.Footnote 47 When thought of in this way, comparative law justifies the use of legal solutions elaborated in foreign legal orders which have historical communalities with the domestic regime. There is also another version of the genetic theory. The cultural and social differences between legal contexts are seen by some courts as unbridgeable, even if these contexts historically share the same origin. This standpoint stems from the idea that domestic legal experiences, and the set of general and particular norms they originate, cannot be reproduced.Footnote 48 Consequently, this version of the genetic theory opposes both comparative reasoning, when it is extended to alien legal cultures, and the idea of a global uniform law, which is seen as pursuing the domain of one particular legal culture over others. Therefore, the genetic approach provides reasons which underpin either a positive or a negative use of historical-comparative reasoning (C4): when used negatively, it leads judges to refuse the relevance of foreign law in legal adjudication or to use comparative reasoning to differentiate their own legal order from other legal orders;Footnote 49 on the contrary, a positive use justifies the transplant of foreign legal solutions into the domestic scenario.Footnote 50 The genetic approach can also justify the use of consequential-comparative reasoning (C3), which either vindicates the use of a foreign norm as an interpretive tool or excludes it from the set of norms that are considered suitable for legal comparison.
(D3) Reflexive theory of comparative law. Those who endorse this viewpoint claim that comparing foreign legal orders with the domestic one helps judges to take a step back from their own legal framework in order to better understand its characteristics. As Mary Ann Glendon paradigmatically pointed out, “comparative law does not provide blueprints or solutions. But awareness of foreign experiences does lead to the kind of self-understanding that constitutes a necessary first step on the way toward working out our own approaches to our own problems.”Footnote 51 In other words, comparative reasoning is useful insofar as it leads judges to recognize false domestic necessities, to elucidate social needs and purposes, or to forecast the consequences of a regulation within the domestic legal scenario. When looking at the use of comparative reasoning by courts, two versions of the reflexive theory can be identified. The first version, which could be called internal reflexive theory, states that by looking at foreign law judges do not seek to achieve uniformity among a variety of legal orders but rather recognize the uniqueness of local legal experiences. In this sense, comparative reasoning is an instrument of self-reflection, which makes domestic judges aware of the peculiarity of their own legal order.Footnote 52 On the contrary the second version of reflexive theory, that we could call external, takes into account the fact that, in the age of globalization, “citizens around the world are increasingly exposed to similar or even identical cultural influences” and face the same social and political problems, such as climate change and the threat of terrorism.Footnote 53 These common sources of social and political change tend to lead to parallel changes in domestic legislations and adjudication. In this sense, comparative reasoning is not simply a means of self-reflection but may provide a clearer insight into some evolutionary trends of regulation around the world which could be usefully considered in domestic law.
When interpreted as a normative discourse, therefore, reflexive theory does not license judges to legal borrowing or transplant. Foreign legal materials should not be used to fill gaps in domestic law nor should they be used directly to interpret domestic legal provisions. Legal comparison has an indirect effect on legal adjudication as it clarifies the internal or the external context of adjudication. When identifying the foreign norms to be compared with the domestic norms, reflexive theory licenses a wide range of argumentative tools. It is compatible with arguments from purpose (C1), arguments from principle (C2), arguments from consequences (C3) and historical-genetic arguments (C4). At the same time, however, this normative standpoint strongly influences the way in which legal comparison is carried out. In fact, it weakens the coherence relation between foreign and domestic norms generally required by comparative arguments, and presents foreign legal materials as a simple source of “inspiration” for the judge.Footnote 54
All that being said, the general structure of comparative reasoning in contemporary adjudication can be outlined with the following scheme:
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The scheme shows under what argumentative conditions the use of comparative reasoning is justified in contemporary adjudication. These conditions are seen as sets of premises, inferentially articulated, which outline the alternative paths of legal justification a court may follow.Footnote 55 The scheme allows both a top-down and a bottom-up reading. If one reads it starting from the bottom, the scheme shows the alternative lines of argument that a court can resort to in order to prove that a certain use of foreign law is consistent and reasonable. For instance, the standard positive form of comparative reasoning (A1) is justified when the domestic and foreign norms are relevantly similar (B1); the foreign norm which has a similarity relationship with the domestic one can be selected either by an argument from purpose (C1), an argument from principle (C2), an argument from consequence (C3) or a historical-genetic argument (C4); if the foreign norm is chosen on the basis of purposive considerations, then the court subscribes to either a universalist (D1) or a genetic theory of comparative law (D2). (Notice that the inferential relation of (C1), (C2), (C3), (C4) with (D3) is marked with a broken line; it is so because the reflexive theory does not justify standard interpretive and integrative uses of comparative reasoning, i.e., the requirement of a coherence relation between a domestic and a foreign legal norm.) Conversely, a top-down reading of the scheme outlines how judges can consistently use comparative reasoning if they subscribe to a certain normative theory of comparative law.
It is worth noting that these sets of justification conditions cannot be reduced to the criteria of logical validity of legal arguments, nor do they follow from the general principles of practical discourse which govern an ideal communicative situation,Footnote 56 nor do they purport to provide a moral or political evaluation of the ways in which courts make reference to foreign law in adjudication. The justification conditions outlined above have been reconstructed by examining what courts in fact claim and do in contemporary legal practice, and depend on the material criteria of legal correctness that are accepted in the considered legal orders. So, they are a posteriori and revisable. Their function is to show what discretionary choices are actually made by courts when referring to foreign law in legal adjudication, and under what circumstances these choices are consistent and reasonable according to the argumentative standards followed by the same courts.
There is one more point to consider in this section. We have seen that the diverse theoretical standpoints on legal comparison are not neutral in the courtroom. Judges explicitly or implicitly rely on theoretical debates concerning the nature and scope of comparative law in order to lay down the normative foundation of their ruling. This has some interesting consequences on the impact of scholarly reflection and research on legal practice. Let us consider, for instance, the doctrines of “cross-fertilization” and “judicial dialogue” mentioned at the outset, which typically endorse a universalist theory of comparative law. In fact, these doctrines work as a sort of self-fulfilling prophecy in legal practice.Footnote 57 The scientific explanation of what happens when courts rely on foreign law turns out to be a prediction that directly or indirectly causes itself to become true. It is so because courts use the explanation of their practice provided by legal scholars as a normative premise in the justification of their ruling, thereby determining the existence of the phenomenon that this explanation purports to account for. When this takes place, theoretical standpoints are actually used as meta-rules of legal justification, which are apt to underpin certain judicial choices and to reject others.
6. Is Comparative Reasoning Changing the Nature of Law?
Bearing in mind the foregoing analysis, we can now return to the question asked at the beginning: does reference to foreign law by courts reflect a change in the rule of recognition which characterizes contemporary legal orders, or even a change in the nature of law?
On the one hand, I am strongly sympathetic with Schauer’s view according to which interpretive arguments are a relevant component in determining how a law should be read in a given social and institutional community. Judicial argumentation makes explicit the reasons that justify a judicial decision and leads us to identify the sources of law in a legal order. So, it is plausible to say that the judicial use of foreign law as an authoritative source of legal obligation would make a difference to the rule of recognition and the characteristics of legal orders in general. On the other hand, the idea that foreign law has become authoritative without being made so by a domestic authority, and that comparative reasoning by courts is changing the nature of law, needs the closer scrutiny I will provide here.
As we have seen in the introductory section of this article, according to Schauer a legal norm is authoritative when it provides content-independent reasons for action to its addressees: “We think of authority as content-independent precisely because it is the source and not the content of the directive that produces the reasons for following it. And so, when a rule is authoritative, its subjects are expected to obey regardless of their own evaluation of the rule or the outcome it has indicated on a particular occasion.”Footnote 58 Now, if foreign law as such became authoritative, this would change the nature of law in the sense that the characteristics typically or overwhelmingly associated to this social phenomenon should be amended to include foreign sources. In Schauer’s view, the nature of a human artifact such as law is not to be explained by reference to the necessary and sufficient properties for its existence but rather by what commonly or generally characterizes the phenomenon being examined.Footnote 59 Thinking of foreign law as establishing legal obligation, for example, would change the identity criteria of legal orders, the long-established idea of positive law as the result of a supremacy claim of one legal order over others, and the role that law plays in forming the identity of a nation-state.Footnote 60
It is beyond the purpose of this article to discuss whether legal authority is content-independent and how an inquiry into the nature of law should be conceived.Footnote 61 For the sake of argument, I shall take Schauer’s theoretical assumptions for granted and examine whether his assessment of the use of comparative reasoning by courts is corroborated in any way by facts. To do this, some observations are in order here. Firstly, we have seen above that comparative arguments can be used with respect to their content in a positive and negative way. In the latter case, comparative reasoning supports the claim according to which foreign law is not authoritative in the domestic legal order. Foreign legal materials are here taken into account in order to protect domestic sources of law from the influences of foreign authorities. Obviously, this does not prove that foreign law cannot be authoritative by special or constitutional law but simply that comparative reasoning may justify the claim that foreign legal norms have no legal authority in a domestic legal regime. Secondly, in the examples considered so far courts make reference to foreign law as both a content-independent and a content-dependent reason for action. However, foreign legal materials are typically seen as content-independent reasons by those courts which consider reference to foreign law as superfluous or illegitimate. According to these courts, the fact that legal authority is content-independent makes foreign law irrelevant to domestic adjudication. On the contrary, those courts which regard the practice of using foreign reference in adjudication as valuable and legitimate typically treat foreign legal materials as content-dependent reasons: the relevance of foreign law in legal adjudication depends on its merits or demerits.Footnote 62 As a consequence, from an empirical point of view, there is no clear evidence in the systems we are considering of an evolving process by which foreign sources of law become authoritative or binding in domestic legal orders. Thirdly, even if foreign law was used in a positive way and as a content-independent reason for adjudication, this would not be necessarily symptomatic of a change in the rules of recognition. When justifying their ruling, courts usually set up a complex argumentative path which includes several inferentially connected legal arguments. Some of these arguments are sufficient or necessary to justify a judicial conclusion: they make explicit what in fact counts as law in a given legal order. Thus, the legal reasons they express can be considered a part of the existing rule of recognition. On the other hand, some arguments are merely optional: they are used to strengthen the conclusion a court has reached but are not incorporated in the rule of recognition; what counts as law does not depend on them.Footnote 63 It can be said therefore that comparative reasoning seems to make a difference in what counts as law only if foreign law is used as both a content-independent and a sufficient or necessary reason for adjudication. Now, the important question is whether foreign law is used this way in contemporary legal practice. As far as we can see in the jurisdictions considered in this article, this does not seem to be the case.Footnote 64 Let’s consider two examples that might seem to support Schauer’s thesis.
In The State v. Makwanyane, the Constitutional Court of South Africa was asked whether section 277(1)(a) of the Criminal Procedure Act of 1977—according to which the death penalty is a competent sentence for murder—was consistent with the Republic of South Africa Constitution of 1993, which had come into force after the conviction of the defendant. The Court was to determine whether the death penalty was in breach of section 11(2) of the new Constitution, which prohibits “cruel, inhuman and degrading treatment or punishment.” To justify the settlement of this dispute, the court resorted only to foreign law: the South African Court took into consideration the approach of a large number of foreign legal orders to the same issue, and examined how foreign courts had interpreted analogous constitutional provisions.Footnote 65 The court here considered foreign law as a sufficient reason for justifying its ruling on the matter. It should be pointed out, however, that the South African Constitutional Court set up its argumentation this way in keeping with section 35(1) of the Constitution, according to which “In interpreting the provision of this Chapter a court of law […] may have regard to comparable foreign case law.”Footnote 66 Therefore, the use of foreign law as a sufficient condition for legal justification in Makwanyane does not give evidence of a change in the existing rule of recognition, since domestic law explicitly permits reliance on comparable foreign legal materials. Foreign law is here a conclusive reason for adjudication because domestic law endows it with legal authority.
The adjudication of the European Court of Human Rights (ECtHR) provides a second example worth considering for our purposes. The European Convention of Human Rights (ECHR) confers upon the ECtHR compulsory jurisdiction over individual applications claiming a violation of Convention rights, once national remedies have been exhausted. Under Articles 8-11 of the ECHR, however, Member States may limit some of the rights protected by the Convention if those limitations “are necessary in a democratic society in the interest of national security or public safety, for the prevention of disorder or crime, for the protection of rights and morals, or for the protection of the rights and freedoms of others.” In order to determine whether a rights limitation by a Member State is necessary, the ECtHR works out a necessity test based upon comparative reasoning. If the court finds that the majority of Member States consider the restriction under review as a necessary means to achieve one of the domestic goals listed above, then this limitation falls under the margin of appreciation of those States and does not infringe the Convention. The ECtHR is to adopt comparative reasoning in order to work out the necessity test: considering foreign law is here a necessary means for justifying ECtHR’s ruling. Nevertheless, this fact does not turn national laws into sources of legal obligation within the framework of the ECHR’s regime. Comparative reasoning simply shows how the multilevel structure of the Convention works: this kind of reasoning displays how the legal orders of the Member States, on the one hand, and ECHR legal order, on the other, are connected to one another as a result of the Convention itself.Footnote 67
Finally, Schauer’s claim generates a further worry distinct from the above examples. If a legal norm originating in a foreign legal order were treated by domestic courts as a sufficient or necessary reason for adjudication, and this occurred independently of any domestic provision permitting the use of foreign law, then this norm could no longer be considered a foreign legal source within the jurisdiction: it would be incorporated as such into the domestic legal order through judicial decision-making. But claiming that comparative reasoning establishes a coherence relationship between two norms belonging to the same legal order would be self-contradictory: the reasoning of the court could not be considered a form of legal comparison by definition since it would not be comparing two legal orders. One might counter this objection by claiming that Schauer is actually describing an evolutionary process. At the beginning, courts rely on foreign law for comparative purposes and consider comparative reasoning as an optional means of legal justification. Courts then begin to treat foreign law as authoritative, thereby changing the rule of recognition of their legal order. By the end of the process, therefore, courts would have changed what counts as law in their own legal regime. However, this reconstruction does not truly reflect what courts actually say and do. If we look at legal practice, when courts make reference to foreign legal norms they do not claim that these norms are a part of their own legal orders: courts simply treat foreign law as a foreign legal item which is worth comparing to domestic law. Nor could courts do otherwise; in fact, if foreign law were considered part of the domestic legal order according to a new rule of recognition, no comparison would be needed.
To sum up, comparative reasoning is neither sufficient nor is it necessary for justifying judicial decisions in contemporary legal practice. Even in cases where reliance on foreign law appears conclusive, this simply indicates either the existence of a domestic norm permitting courts to rely on foreign legal materials, or shows how different legal orders are interlocked in supranational regimes. Outside of these cases, courts treat foreign law as merely persuasive when performing comparative reasoning. The same can be said for those cases where a foreign ruling is compared to domestic law only because it is widely cited in other jurisdictions around the world or is provided by prestigious and highly regarded courts. When this occurs, foreign law does provide content-independent reasons for adjudication but is not legally authoritative in the domestic legal order in question. In such cases, prestigious courts of other jurisdictions exert a form of practical authority on domestic judges which explains why the ruling of these highly regarded courts is persuasive.Footnote 68
As a result, if we think of legal authority as content-independent, as Schauer does, and analyze the kind of reasons provided by foreign law in comparative reasoning, then the current uses of foreign law by courts cannot be seen as a practice which is changing the nature of law. This does not mean to say that the judicial use of foreign legal materials will not give rise to new forms of legal organization in the near future. The fact that comparative reasoning is typically or overwhelmingly used by courts as a persuasive means of legal justification is not without consequences. The persuasive character of foreign law may bring a court to accept the substantive, content-dependent reasons underlying a foreign solution to a judicial dispute. Now, if the acceptance of these reasons leads courts to consider foreign law as a necessary or sufficient means for justifying their ruling, independently of any domestic provision permitting them to make reference to foreign legal sources, then we will face a change in the rule of recognition and in the distinctive characteristics of contemporary law.Footnote 69 As previously mentioned, claiming that such a change is already in place might be an effective way to bring it about.