University of Transnational Business Law

The Argument from Coherence

by Stefano Bertea


I. Introduction

Coherence is widely argued to be a value of special significance in the legal domain. It is in particular Neil MacCormick’s seminal work on legal reasoning that has driven theorists to emphasise the importance of coherence as an ideal feature of law and a regulative criterion of judicial argumentation.[1] Far from merely serving philosophical idealisation, however, the idea of coherence is deeply ingrained in the practice of contemporary legal systems: courts commonly invoke arguments from contextual harmonisation, general principles, analogy, and precedents, all of which use the notion of coherence, though each to a different extent.[2] Nonetheless the relationship between coherence and law is not a linear one. Legal orders seem to require an appeal to coherence at the same time as they make this appeal problematic.
On the one hand, “coherence is an elementary postulate of rationality” that promises to soften the tension possibly obtaining between legal authority and rationality by enabling one to treat rationally authoritative issuances.[3] Furthermore, coherence and law seem to be able to walk together easily. Coherence relates to the idea that the system has to make sense as a whole. And making sense as a whole is a precondition of intelligibility, which in turn is a requirement essential to law, at least to the extent that law is understood as an institution purposing to guide actions. In addition, coherence can help us analyse a normative order. Legal institutions are systems of norms, i.e. ordered arrangements of prescriptive standards, not mere collections[4] of directives. Similarly, what is coherent forms a well-organised unit rather than a chaotic assemblage of possibly inconsistent normative statements. Finally, as Kress observes, ‘the idea that law is a seamless web, that it is holistic, that precedents have a gravitational force throughout the law, that argument by analogy has an especial significance in law, and the principle that all are equal under the law’ enable coherence to have a special claim on us.
On the other hand, the relationship between coherence and law can be problematic. The problematic side of this relationship emerges when a legal system is looked at as a polycentric entity with a plurality of sovereign powers that coexist and interact with one another in many ways. Whilst coherence (on some interpretations of it) connects with the idea of unity, the pluralist nature of law sits poorly with the ideal of unity. Further, in fact law may well fall short of making up ‘a coherent rational system.’ On a realistic and demythologising outlook, thus, far from being a coherent set shaped by rational criteria law appears to be ‘a hodgepodge of norms derived from the conflicting ideologies and the necessities which prevailed from time to time over the many years of evolution.’[5] Finally, even the theorists who are sympathetic to the idea of coherence emphasise its limits and judge it to be a weak standard of justification. According to MacCormick, for example, coherence is ‘a relatively weak constraint’ that ‘determines only what we might call the “weak derivability” of a ruling or decision from the pre-existing law:’[6] coherence can secure a relatively ordered and structured normative environment, but it cannot by itself make sure that such ordering and structuring results in a fair or a substantially correct system.
In sum, the practice of appealing to coherence in legal reasoning needs theoretical foundation. Consequently, over the last few decades several legal theorists have become increasingly concerned with coherence and have systematically attempted to elucidate the practice of appealing to coherence in adjudication. We owe it to their efforts if we now have a better understanding of the nature, scope and limitations of both a notion as inherently elusive and slippery as coherence and the practice to refer to this notion in legal argumentation.
In Section II various definitions of the notion of coherence are discussed and various types of coherence are noted. Then in Section III the topic of arguing from coherence is discussed from the perspective of coherence as a standard of justification and different approaches to the argument from coherence are highlighted. I conclude by suggesting that the conception of coherence as the ideal that the system of the law has to make sense as a whole implies that we take the pluralism of the law seriously and strive to make the law intelligible without denying its multiple nature.
II. The notion of Coherence
A. Definition of Coherence

There is wide agreement among contemporary legal theorists over the characterisation of coherence in the negative as lack of inconsistencies. Yet, it is still a question how coherence might be defined in positive terms. Coherence is generally held to be something more than the logical consistency of propositions. While what this “something more” amounts to is not always made clear by legal theorists, it is widely claimed that coherence should at least entail consistency, comprehensiveness and completeness (at least to some degree), support (of varying scope and force), and cross-connection and mutual justification between the parts of a whole. Thus, coherence is often defined in figurative language as the equivalent of ‘hanging together,’ ‘making sense as a whole,’ ‘cohesion,’ ‘consonance,’ and ‘speaking with one voice.’[7] In this sense, coherence is argued to be a form of supportive rationality, a sort of entailment, a ‘kind of internal interconnectedness’ or ‘plausible connection’ that is weaker than the logical link.[8] The type of interdependence coherence hints at is a connection that is not linear and asymmetrical, but circular and symmetrical. This circular and symmetrical dimension allows us to establish a correlation between coherence and the idea of reflective equilibrium. The process of going back and forth – the practice by which a general concept is modelled in the light of the specificities of a particular case, and vice versa – is typical not only of reflective equilibrium but also of coherence judgements: to argue from coherence is to strike a reflective equilibrium, to ponder reasons, to weight potentially colliding criteria.
B. Types of Coherence

These definitions allow for further internal distinctions among types of coherence. An important distinction is the partition between epistemic coherence and constitutive coherence. Epistemic coherence is a condition of justified beliefs; constitutive coherence is a criterion of either correctness or truth.[9] Epistemic coherence is predicated of a conviction that is considered to be justified and coheres better than other convictions with our system of belief. By contrast, we use constitutive coherence to argue that coherence is what makes decisions right or propositions true. Constitutive coherence is the most relevant and the most commonly invoked type of coherence in legal discourse. The object of (constitutive) coherence considerations can be either facts or norms. Following MacCormick, we can call ‘narrative coherence’ the kind used in ‘drawing inferences of fact from evidentiary facts,’ and ‘normative coherence’ the kind used in relation to norms.[10] Normative coherence applies to points of law rather than to matters of fact, meaning that it can apply either to a normative system or to reasoning with norms. When applied to a normative system, coherence is considered a feature, actual or ideal, of that system, and is therefore a systemic notion: a legal system is coherent if its components fit together, either all of them (global systemic coherence) or some of them (in which case we have local systemic coherence).
III. Arguing from Coherence
A. Coherence as a standard of justification

Normative coherence can also be used in legal reasoning as a standard of justification to evaluate the arguments put forward in justifying single decisions. Coherence as a criterion of adjudication brings us very close to the argument from coherence. This can be defined as the interpretive canon enabling one to establish and justify a specific standpoint by invoking the need to contribute to, and to preserve, the coherence – namely, the internal connectedness – of a set of entities. Then, the argument from coherence individuates the general form of the various possible argumentative structures whose unifying trait consists in bringing the idea of coherence into play to justify a given standpoint. As a standard of adjudication coherence can be used to assess either whether each of the arguments adduced in support of a specific decision is coherent with the others, or whether a given ruling falls in line with the fundamental principles of a legal system. Either way we advance a thesis about what is correct adjudication. But, in the former case a decision is found to be right if the arguments it is based on are well connected with one another. Coherence is therefore predicated of arguments. By contrast, in the latter case coherence is predicated of rulings: a decision is considered correct if it coheres with the rest of the system, the rest of the system being the norms of a specific branch of law (local adjudicative coherence) or all the norms in force in a given legal order (global adjudicative coherence).[11] So, the appeal to coherence in legal adjudication helps decision-making authorities to perform their duty to be faithful to pre-existing law. Coherence is a backward-looking, conservative criterion of adjudication, a standard that places emphasis on the past and on the obligation to adhere to such law as was enacted beforehand. As Raz puts it, coherence ‘forces one to decide in a certain way because past decisions are of a certain character. Coherence gives weight to the actual past, to the concrete history of the law.’[12] In this context, coherence plays the role of a normative criterion: to accept coherence as a standard of adjudication is to claim that judges should follow the letter of the law only to the extent that the coherence of the system is not thereby jeopardised; for otherwise, it is the spirit of the law that must be followed, and the law must so be extended as to preserve coherence within the system.
B. Different Approaches to the Argument from Coherence

Approaches to coherence in the context of adjudication can be more or less imperialistic. An extreme position in this regard is the thesis that an argument’s coherence with other arguments or a ruling’s coherence with the system is a necessary and sufficient condition for that argument or ruling to be justified. Here, adjudication is reduced to a test of coherence and coherence is considered a strong standard of justification, a standard that provides the one right answer to each and every case. Also, coherence is viewed as a specific instance of a wider effort to reduce complexity, to find a single principle whose application provides a clear and definitive solution to all legal dilemmas (monistic conception).
A more moderate view argues that while an argument or a ruling needs to be coherent to be correct, there are standards in addition to coherence that come into play in rational justification. Showing a set of arguments to be internally coherent, or a ruling to be externally coherent, is only one step towards justification. No decision can be justified on this basis unless other values and principles are brought to bear. This makes coherence a weak standard of justification since adjudication should not be based on coherence alone, but should take into account other criteria as well. Adjudication is not about finding the most general and abstract principle, the one that justifies the others; it is rather a balancing of different criteria among which no preset relation of priority exists. Further, there is no special connection between coherence and unity: the coherence test has nothing to do with showing that many or all of a court’s decisions fall into the same line. Quite the contrary, ‘coherence in legal reasoning assists the judge in pursuing an ideal: to make sense of the diversity of law.’[13]
In other words, to appeal to coherence is to take pluralism seriously and strive to impart an order to a plural entity, making it intelligible without denying its multiple nature. Therefore, coherence does not commit us to ignoring the law’s complexity or to espousing an unrealistic ideal of a tensionless legal order. On this understanding, accepting coherence as an important value in law does not prevent us from recognising that law results from pragmatic compromises and reflects the disparate ideologies and interests of the changing political forces that have governed a country in different times.
Related entries

theories of Adjudication,  Argumentation in the Law,  Analogy,  Argumentation based on legal principles,  Practical Argumentation in the Justification of Judicial Decisions,  Weighing and balancing in legal argumentation,  Progressive and regressive reasoning in the law.
Essential readings

Alexy R. and A. Peczenik.: 1990, ‘The Concept of Coherence and Its Significance for Discursive Rationality’, Ratio Juris 3, 130-147.

Bertea, S.: 2005, ‘The Arguments from Coherence’. Oxford Journal of Legal Studies 25, 369-391.

Dworkin, R.: 1986, Law’s Empire, Fontana, London.

Kress, K.: 1999, ‘Coherence’, in D. Patterson (ed.), A Company to Philosophy of Law and Legal Theory, Blackwell, Oxford, 533-552.

Levenbook, B.: 1984, ‘The Role of Coherence in Legal Reasoning’, Law and Philosophy 3, 355-374.

MacCormick, N.: 1984, ‘Coherence in Legal Justification’, in A. Peczenik (ed.), Theory of Legal Science, Reidel, Dordrecht, 235-251.

MacCormick, N.: 1994, Legal Reasoning and Legal Theory (1978), Clarendon, Oxford.

Peczenik, A.: 1990, ‘Coherence, Truth and Rightness in the Law’, In P. Nerhot (ed.), Law, Interpretation and Reality. Kluwer, Dordrecht, 275-309.

Raz, J.: 1994, ‘The Relevance of Coherence’, in J. Raz, Ethics in the Public Domain. Essays in the Morality of Law and Politics, Clarendon, Oxford, 277-325.

Soriano, L.M.: 2003, ‘A Modest Notion of Coherence in Legal Reasoning. A Model for the European Court of Justice’, Ratio Juris 16, 296-323.
Footnotes

[1] In particular, see N. MacCormick, Legal Reasoning and Legal Theory (1978) (Clarendon, 1994), at pp. 152-194.

[2] For an introduction to the main arguments currently employed by judges and legal practitioners within national legal systems around the world, see N. MacCormick and R. Summers (eds.), Interpreting Statutes (Dartmouth, 1991).

[3] R. Alexy, ‘Jürgen Habermas’s Theory of Legal Discourse,’ (1996) Cardozo Law Review 17, pp. 1027-1034, at p. 1028.

[4] K. Kress, ‘Coherence’, in D. Patterson (ed.), A Company to Philosophy of Law and Legal Theory (Blackwell, 1999, pp. 533-552) at p. 536.

[5] J. Raz, ‘The Relevance of Coherence’, in J. Raz, Ethics in the Public Domain. Essays in the Morality of Law and Politics (Clarendon, 1994) at p. 281.

[6] N. MacCormick, ‘Coherence in Legal Justification’, in A. Peczenik (ed.), Theory of Legal Science (Dordrecht: Reidel, 1984), 235-251 at p. 244.

[7] We find ‘making sense as a whole’ and ‘hanging together’ in the description of coherence put forward by N. MacCormick, ‘Coherence in Legal Justification’, in A. Peczenik (ed.), Theory of Legal Science (Reidel, 1984, pp. 235-251) at p. 235; ‘cohesion’ is found in G. Zaccaria, ‘Hermeneutics and Narrative Comprehension’, in P. Nerhot (ed.), Law, Interpretation and Reality (Kluwer, 1990, pp. 251-274) at p. 269; and ‘consonance’ in V. Villa, ‘Normative Coherence and Epistemological Presuppositions of Justification’, in P. Nerhot (ed.), Law, Interpretation and Reality (Kluwer, 1990, pp. 431-455) at p. 433. The expression ‘speaking with one voice’ is used by Ronald Dworkin in his treatment of integrity (see R. Dworkin, Law’s Empire (Fontana, 1986), at p. 165).

[8] These two expressions are found in B. Levenbook, ‘The Role of Coherence in Legal Reasoning’, (1984) Law and Philosophy 3, pp. 355-374 at p. 362; and V. Villa, ‘Normative Coherence and Epistemological Presuppositions of Justification’, in P. Nerhot (ed.), Law, Interpretation and Reality (Kluwer, 1990, pp. 431-455) at p. 433 respectively. On supportive rationality, see A. Peczenik, ‘Coherence, Truth and Rightness in the Law’, in P. Nerhot (ed.), Law, Interpretation and Reality (Kluwer, 1990, pp. 275-309), at pp. 279-280.

[9] The distinction is drawn in these terms by J. Raz, ‘The Relevance of Coherence’, in J. Raz, Ethics in the Public Domain. Essays in the Morality of Law and Politics (Clarendon, 1994) at p. 263, among others.

[10] See N. MacCormick, ‘Coherence in Legal Justification’, in A. Peczenik (ed.), Theory of Legal Science (Reidel, 1984, pp. 235-251) at p. 235.

[11] See B. Levenbook, ‘The Role of Coherence in Legal Reasoning’, (1984) Law and Philosophy 3, pp. 355-374, at pp. 367-374.

[12] J. Raz, ‘The Relevance of Coherence’, in J. Raz, Ethics in the Public Domain. Essays in the Morality of Law and Politics (Clarendon, 1994) at p. 302. Cf. B. Levenbook, ‘The Role of Coherence in Legal Reasoning’, (1984) Law and Philosophy 3, pp. 355-374 at p. 359.

[13] L. M. Soriano, ‘A Modest Notion of Coherence in Legal Reasoning. A Model for the European Court of Justice’, (2003) Ratio Juris 16, pp. 296-323, at p. 302 (original emphasis).