An Automated System for Argument Invention in Law Using Argumentation and Heuristic Search Procedures*

Abstract. A heuristic search procedure for inventing legal arguments is built on two tools already widely in use in argumentation. Argumentation schemes are forms of argument representing premise‐conclusion and inference structures of common types of arguments. Schemes especially useful in law represent defeasible arguments, like argument from expert opinion. Argument diagramming is a visualization tool used to display a chain of connected arguments linked together. One such tool, Araucaria, available free at http://araucaria.computing.dundee.ac.uk/ , helps a user display an argument on the computer screen as an inverted tree structure with an ultimate conclusion as the root of the tree. These argumentation tools are applicable to analyzing a mass of evidence in a case at trial, in a manner already known in law using heuristic methods ( Schum 1994 ) and Wigmore diagrams ( Wigmore 1931 ). In this paper it is shown how they can be automated and applied to the task of inventing legal arguments. One important application is to proof construction in trial preparation ( Palmer 2003 ).     

What is the Theory Legal Argumentation For?

The paper aims to present the legal theories of legal argumentation constructed in the last century, organised into two groups: the precursors (Viehweg, Perelman and Toulmin) and the authors of the standard theory (MacCormick and Alexy). Then, some criticisms about all these conceptions are presented. And finally, an outline of a theory of legal argumentation is made, capable of overcoming some of the previous criticisms. The fundamental idea for this is to build a very abstract concept of argumentation that could then allow various interpretations or conceptions of legal argumentation. From here, one would be in a position to find an answer to the three main argumentative questions raised by legal practice: how to analyse an argument, how to evaluate it, how to argue.

     

The Strategic Use of Formal Argumentation in Legal Decisions

In legal decisions standpoints can be supported by formal and also by substantive interpretative arguments. Formal arguments consist of reasons the weight or force of which is essentially dependent on the authoritativeness that the reasons may also have: In this connection one may think of linguistic and systemic arguments. On the other hand, substantive arguments are not backed up by authority, but consist of a direct invocation of moral, political, economic, or other social considerations. Formal arguments can be analyzed as exclusionary reasons: The authoritative character excludes—in principle—substantial counterarguments. Formal arguments are sometimes used to conceal value judgements based on substantial arguments. This paper deals with reconstructing problems regarding this strategic use of formal arguments in legal decisions, with a focus on linguistic argumentation.     

“This Argument Fails for Two Reasons…”: A Linguistic Analysis of Judicial Evaluation Strategies in US Supreme Court Judgments

The centrality of argumentation in the judicial process is an age-old acquisition of research on legal discourse. Notwithstanding the deep insights provided by legal theoretical and philosophical works, only recently has judicial argumentation been tackled in its linguistic dimension. This paper aims to contribute to the development of linguistic studies of judicial argumentation, by shedding light on evaluation as a prominent aspect in the construction of the judge’s argumentative position. Evaluation as a deep structure of judicial argumentation is studied from a discursive point of view entailing the analysis of a sample of authentic judicial language. Evaluative lexis is investigated within a single genre of judicial discourse, i.e. judgments, instantiated by a corpus of US Supreme Court judgments. Findings show that judges use diversified strategies to take stance as they organise their argumentative discourse: from easily recognisable verbal and adjectival tools to more finely-grained discourse elements such as the encapsulating pattern ‘this/these/that/those + labelling noun’.     

Understanding Blended Multi-Source Arguments as Arguments from Partial Analogies

This paper identifies a type of multi-source (case-based) reasoning and differentiates it from other types of analogical reasoning. Work in cognitive science on mental space mapping or conceptual blending is used to better understand this type of reasoning. The type of argument featured herein will be shown to be a kind of source-blended argument. While it possesses some similarities to traditionally conceived analogical arguments, there are important differences as well. The triple contract (a key development in the usury debates of the fifteenth and sixteenth centuries) will be shown to make use of source-blended arguments.     

法律的道德论证——一个语言哲学的视角

对法律进行道德论证会遇到“明希豪森困境”和“休谟问题”的干扰,语言学规则为法律论证提供了一种新的可能,虽然语言学论证中也会有诸如概念含义过于复杂等困难,但是,作为一种不同于传统法律论证理论,其所提供的解释视角和评判标准则是很有价值的。     

A Formal Model of Legal Argumentation

Abstract . The paper gives a formal reconstruction of some fundamental patterns of legal reasoning, intended to reconcile symbolic logic and argumentation theory. Legal norms are represented as unidirectional inference rules which can be combined into arguments. The value of each argument (its qualification as justified, defensible, or defeated) is determined by the importance of the rules it contains. Applicability arguments, intended to contest or support the applicability of norms, preference arguments, purporting to establish preference relations among norms, and interpretative arguments are also formalised. All those argument types are connected in a unitary model, which relates legal reasoning to the indeterminacy of legal systems, intended as the possibility to develop incompatible defensible arguments. The model is applied to permissive norms and normative hierarchies, and is implemented in a Prolog program.     

修辞论证的方法——以两份判决书为例

修辞在法官论证中的作用十分重要。在具体论证中,法官往往充分利用唤起情感的修辞技巧,并且在判决书中修辞对论证具有构成性意义。此外,无论是修辞论证所重视的共识还是论证本身所反映的实践合理性,其合理性基础均是语用学规则。     

Argumentation and Interpretation in Law

Abstract
The author proceeds from a brief elucidation of the concept "argumentation" through a more extended account of substantive reasons in pure practical argumentation and of institutional argumentation applying "authority reasons" as grounds for legal decisions to an initial account of the nature and place of legal interpretative reasoning. Then he explores the three main categories of interpretative arguments, linguistic arguments, systemic arguments and teleological/deontological arguments; and he examines the problem of conflicts of interpretation and their resolution. His conclusion is that legal argumentation is only partly autonomous since it has to be embedded within widerelements of practical argumentation.     

Regulating germ-line gene therapy to avoid sliding down the slippery slope

Many arguments can be made for or against various regulatory approaches towards germ-line gene therapy and its associated research. A popular conclusion is that it ought to be prohibited, and this is commonly defended by use of a slippery slope argument. This paper will begin by outlining the regulatory approaches adopted towards germ-line gene therapy in EU countries, demonstrating the popularity of the restrictive approach. The slippery slope argument will then be examined. A number of variants of the slippery slope argument will be distinguished, highlighting the conceptually different claims made by each. Finally, examples of slippery slope arguments often invoked to support the prohibition of germ-line gene therapy will be examined with regard to the conditions that each must satisfy to form a theoretically sound argument. I will argue that these conditions are rarely given sufficient consideration. For the purposes of this paper, "germ-line gene therapy" is defined as the deliberate genetic modification of germ cells (sperm or oocytes), their precursors, or the cells of early embryos where the germ-line has yet to be segregated.     

A Modest Notion of Coherence in Legal Reasoning. A Model for the European Court of Justice

Abstract. The aim of this article is to propose a theoretical theme to explain coherence in legal reasoning. The main argument that this paper wants to put forward is that theories of coherence in the legal system should be differentiated from theories of coherence in legal reasoning. These focus on arguments, and on how the given arguments are connected. In particular, the notion of coherence in legal reasoning proposed here is a modest one. The article applies this theme to the case‐law of the European Court of Justice in environmental matters. This provides an example of how to deal with conflicts between incommensurable goods, and how to promote coherence by justifying decisions.

相似文献   

Dichotomies and Oppositions in Legal Argumentation

In this paper we use a series of examples to show how oppositions and dichotomies are fundamental in legal argumentation, and vitally important to be aware of, because of their twofold nature. On the one hand, they are argument structures underlying various kinds of rational argumentation commonly used in law as a means of getting to the truth in a conflict of opinion under critical discussion by two opposing sides before a tryer of fact. On the other hand, they are argument structures underling moves made in strategic advocacy by both sides that function as platforms for different kinds of questionable argumentation tactics and moves that are in some instances tricky and deceptive.     

Charles Sanders Peirce, A Mastermind of (Legal) Arguments

In this article, we try to trace the relationship between semiotics and theory of legal reasoning using Peirce’s idea that all reasoning must be necessarily in signs: every act of reasoning/argumentation is a sign process, leading to “the growth of knowledge. The broad scope and universal character of Peirce’s sign theory of reasoning allows us to look for new conciliatory paradigms, which must be presented in terms of possible synthesis between the traditional approaches to argumentation. These traditional approaches are strongly affected by either the dialectical (logical) perspective or the rhetorical perspective on argumentation, while Peirce’s approach tends to reconcile the rhetorical and methodological aspects of reasoning. This reconcilation is best illustrated by Peircean analysis of argument’s logical and rhetorical structure; while the diagrammatic (iconic) analysis of arguments is performed in the system of Existential Graphs (which is Peirce’s major methodological system, designed for the expressions of propositions in point of their relational structure). Obviously, Peirce’s original division of argument parts offered only the characterisation of the sign activity (involved in the process of reasoning), and thus left much to be desired in terms of practical explication.     

Theories of Legal Argumentation and Concepts of Law. An Approximation

This article provides an assessment of the merits of recent theories of legal reasoning. After a quick historical aperçu a number of models of legal argumentation are presented and discussed, with an eye to their mutual connection. An initial conclusion is that universalizability and discursivity are the common features of those models. The focal question dealt with, however, is that of the impact of the argumentative paradigms of adjudication on the very concept of law. Here the contention is that an argumentative style of reasoning contributes to rendering the structure of the law itself and its operations argumentative as well. By so doing the latter are—so to say—civilized and made less truculent. They will thus be able to develop more in conformity with a democratic form of life.     

麦考密克法律论辩理论的经济学解读

麦考密克描述阐释了司法审判中主要的法律论辩形式，包括演绎性证明，后果主义论辩，协调性论辩及一致性论辩。通过对此理论的经济分析，发现论辩主体为什么会采用这些论辩方式、应该如何运用及它们的功能为何，最终都立基于经济学的逻辑。     

融贯性论证与司法裁判的和谐

我们要构建的和谐社会是一个全面和谐的社会,司法裁判的和谐是和谐社会的应有之义.司法裁判的和谐主要体现为,司法裁判具有合法性、合理性和进步性.实现司法裁判的和谐,需要通过融贯性的法律论证进行推动.融贯性论证在程序方面的要求是通过平等方式开展法官与诉讼当事人及其他参与人之间的论辩和对话,在实体方面的要求是充分吸收社会所公认的价值观念.这样作出的司法裁判才具有可接受性,才能实现司法裁判的和谐.     

The Special Case Thesis and the Dual Nature of Law

In this article, I take up two arguments in favor of the discursive model of legal argumentation: the claim to correctness argument and the dual nature thesis. The argument of correctness implies the dual nature thesis, and the dual nature thesis implies a nonpositivistic concept of law. The nonpositivistic concept of law comprises five ideas. One of them is the special case thesis. The special case thesis says that positivistic elements, that is, statutes, precedents, and prevailing doctrines, are necessary for law in order to achieve legal certainty. Without this, law would not be as perfect as it could possibly be. But it says, at the same time, that this alone would not be enough to fulfill the claim to correctness. The claim to correctness refers not only to the real dimension of law, defined by statutes, precedents, and prevailing doctrines, but also to its ideal dimension, defined, first and foremost, by justice. The special case thesis is my oldest thesis. It has remained an essential element of my system over the years. Its connection with four other theses—the Radbruch formula, the human rights thesis, the idea of deliberative democracy, and principles theory—does not change this at all. On the contrary, this connection has lent greater strength to the special case thesis.     

An Acquittal for Epistemicism

Scott Soames argues that consideration of the practice of legal judgement gives us good reason to favor the partial-definition/context-sensitive theory of vagueness against epistemicism. Despite the fact that the value of power-delegation through vagueness is evidenced in practice, Soames says, epistemicism cannot account for it theoretically, while the partial-definition/context-sensitive theory is capable of it. In this paper, I examine the two possible arguments against epistemicism that can be extracted from Soames’s account: (1) an argument based on unknown obligations, and (2) an argument based on power-delegation through vagueness. The first argument tries to convince us that, as based on epistemicism, the law has already decided the borderline cases, so that judges have obligatory decisions even in such cases: therefore epistemicism is inconsistent with the discretion of judges in borderline cases. I show that even if we sympathize with Soames’s intuitions concerning the legal practice, the argument he offers is not conclusive since it is either invalid, unsound, or paradoxical. The second argument holds that only the gaps which the partial-definition/context-sensitive theory predicts give judges the possibility of lawmaking in borderline cases. However, by categorizing the vague laws as imperfect laws, the judges can claim the right of lawmaking without any need to refer to gaps in the law. By neutralizing these arguments, I argue that epistemicism is able to explain the phenomena just as well as the partial-definition/context-sensitive theory.