Modelling Judicial Context in Argumentation Frameworks

Bipolar Argumentation Frameworks (BAFs) are an important class of argumentation frameworks useful for capturing, reasoning with, and deriving conclusions from debates. They have the potential to make solid contributions to real-world multi-agent systems and human-agent interaction in domains such as legal reasoning, healthcare and politics. Despite this fact, practical systems implementing BAFs are largely lacking. In this demonstration, we provide a software system implementing novel algorithms for calculating extensions (winning sets of arguments) of BAFs. Participants in the demonstration will be able to input their own debates into our system, and watch a graphical representation of the algorithms as they process information and decide which sets of arguments are winners of the debate.

This work will introduce a novel combination of two important argumentation related notions. We will start from the well-known basis of Abstract Argumentation Frameworks or AFs, and we will build a new formalism in which the notions corresponding to Toulmin's backings and Pollock's undercutting defeaters are considered. The resulting system, Backing-Undercutting Argumentation Frameworks or BUAFs, will be an extension of the AFs that includes a specialized support relation, a distinction between different attack types, and a preference relation among arguments. Thus, BUAFs will provide a richer representation tool for handling scenarios where information can be attacked and supported.

In this paper a new formal model of argument accrual is proposed as an adaptation of the ASPIC+ framework for structured argumentation. The new model aims to overcome several weaknesses of existing proposals. It is shown to have desirable formal properties that are in line with standard work on formal argumentation, and to be applicable to a range of situations in legal reasoning.

This paper investigates the practical reasoning involved in compliance-related decisions, distinguishing between two scenarios where a state of affairs is evaluated in the light of applicable norms: ex post compliance checking and ex ante compliance choices. While the literature in legal reasoning representation is exclusively focused on compliance checking scenarios, i.e., simulating a digital judge, different factors seem to play a role in the inner deliberation of compliance choices. In this paper we investigate how human agents are influenced in their compliance choices by their own value ranking and risk assessment and how, in turn, the choice affects their preference among alternative interpretations of the law. We contend that contributions from the literature such as the value-based argumentation framework, while focused on ex post judgments, may be able to provide a comprehensive framework for ex ante compliance decisions. The main goal of the research behind this work is to achieve a comprehensive representation of legal reasoning that can be used as a reference for the explanation of automated compliance decisions.

We present a computational model of dialectical argumentation that could serve as a basis for studying elements of legal reasoning. Argumentation is well-suited to decisionmaking in the legal domain, where knowledge is incomplete, uncertain, and inconsistent, We model an argument both as information structure, i.e., argument units connecting claims with supporting data, and as dialectical process, i.e., an alternating series of moves made by opposing sides. Inspired by the legal domain, our model includes burden of proof as a key element, indicating the level of support that must be achieved by a particular side to an argument. Burden of proof acts as a move filter and termination criterion during argumentation and determines the eventual winner. We demonstrate our model by considering two examples that have been discussed previously in the artificial intelligence and legal reasoning literature. INTRODUCTION As the artificial intelligence (AI) and legal reasoning communities are well aware, most decisions are reached against a background of incomplete, uncertain, and inconsistent knowledge (i.e., weak theory domains; Porter, et. al., 1990). The most widely used AI methods for reasoning under uncertainty either rely on an absence of outright contradictions (e. g., probabilistic reasoning; Pearl, 1987) or are unable to support motivated decision-making in the face of inconsistent information (e.g., default reasoning; Ginsberg, 1987). Both solutions put the problem of deciding what to believe outside their respective domains of discourse. Choosing the proposition with highest Permission to copywithoutfee all or part of this material is granted provided that the copies are not made or distributed for direct commercial advantage, the ACM copyright notice and the title of the publication and its date appea, and notice is given that copying is by permission of the Association for Computing Machinery. To copy otherwise, or to republisb, requires a fee andlor specific permission.

Subjectivism, Objectivism and Intuitionism in Legal Reasoning – Avoiding the Pseudos

This article deals with general problem of connection between legal reasoning, legal argumentation and, on the other hand, logic. Although this connection seems obvious since ancient times, its nature is still the subject of non-trivial discussions. The purpose of my study is to explore one important aspect of this connection, namely, is general, or formal, logic necessary and sufficient to determine relevant form of legal reasoning and argumentation? To reach this purpose, method of comparative analysis is employed both synchronically and diachronically. First, in order to prove importance of the issue, a diachronic comparison of several basic approaches is carried out (G.W. von Leibniz, O.W. Holmes, Jr., etc.). Then a comparative analysis of the views of some contemporary experts is carried out, especially Ilmar Tammelo and Stephen Toulmin. It is argued, in the field of law there is a special legal validity that differs significantly from the formal-logical validity. The legal validity is determined directly and mainly by the value of the right not by the value of formal or material truth. It is not the subject of formal logic, but of a special legal logic and, more broadly, informal logic. Therefore, formal logic does not determine relevant form of legal reasoning and argumentation, since, first of all, there is the essential difference between the formal-logical validity and the legal validity. It is argued, formal logic is neither sufficient nor necessary to think like a jurist. In this regard, it is shown that the formal-logical standard of proof is not sufficient to determine the relevant form of valid legal proof. There are at least three standards of legal proof – proof without reasonable doubt, proof by clear and convincing evidence, and proof by preponderance of the evidence. Each of them differs significantly from the formal-logical standard. The conclusion of this research is this: it cannot be said that general logic does not work at all in the field of law. However, in order to reason and argue like a successful jurist, one must to grasp and use, without any exceptions, the special legal logic that belongs to the domain of contemporary informal logic.

Up to the present day, the theories of legal reasoning have been concerned with reasoning in the stages of interpretation and adjudication of laws. However, if a fundamental feature of legal reasoning is that it is actually bound by laws, then the theory of legal argumentation should also consider to what extent legislative argumentation is an assumption of rational legal reasoning: if legal reasoning is, as Alexy states, a special case of the general practical discourse, and the speciality of legal reasoning is a consequence of the requirement of being bound by legal laws, then legislative rationality can be considered a premise of the rationality of law interpretation and adjudication.

The rationality project offered by the current Theory of Legal Argumentation is marked fundamentally by strong silent about emotions, a subject that has been considered, nowadays, a theoretical indifferent, although traditionally has been linked to the study of speech and ethics since ancient times. This modern theoretical gap has the effect of disturbing inability of the current student and legal professional to identify, evaluate and reflect the presence of emotions in argument and, more broadly, in legal practice. This study aims to understand why emotions left the Legal Argumentation Theory and try to provide reasons for them to be studied again. Thus, it is necessary to investigate whether they would be compatible with a rational legal argumentation and, more broadly, with the explanation of the legal system. To achieve this goal, it is necessary to study ancient philosophy, specifically the thought of Aristotle and the Stoic school in order to understand how both have integrated the theme of emotions in his ethics and his rhetoric. Then, we investigate in which historical context comes the Modern Theory of Argumentation, considering the thought of its founders and the following generations. It aims also search to understand the psychology of our time on emotions. In the end, the objective is to identify the good and bad use of emotions in legal reasoning, enabling the subject to be rescued with serious and critical capacity in order to improve the quality of legal discourse.

Several techniques for improving web search have been developed over the last years. Most existing approaches are still limited, mainly due to the absence of qualitative criteria for ranking results and insensitivity to user preferences for guiding the search. At the same time, defeasible argumentation evolved as a successful approach in AI to model commonsense qualitative reasoning with applications in many areas, such as agent theory, knowledge engineering and legal reasoning. This paper presents ARGUENET, a recommender system that classifies search results according to preference criteria declaratively specified by the user. The proposed approach integrates a traditional web search engine with a defeasible argumentation framework.

7 CASE NOTING It is at this point that a case note can be made. The case note has to contain all of the information that enables the case to be used. One of the most important tasks of a law student or, indeed, a legal professional is the ability to read a case and make a usable record of

Legal texts are the foundational resource where to discover rules and norms that feed into different concrete (often XML-based) Web applications. Legislative documents provide general norms and specific procedural rules for eGovernment and eCommerce environments, while contracts specify the conditions of services and business rules (e.g. service level agreements for cloud computing), and judgments provide information about the legal argumentation and interpretation of norms to concrete case-law. Such legal knowledge is an important source that should be detected, properly modeled and expressively represented in order to capture all the domain particularities. This paper provides an extension of RuleML called LegalRuleML for fostering the characteristics of legal knowledge and to permit its full usage in legal reasoning and in the business rule domain. LegalRuleML encourages the effective exchange and sharing of such semantic information between legal documents, business rules, and software applications.

Answer Set Programming is a declarative problem solving approach, initially tailored to modelling problems in the area of Knowledge Representation and Reasoning. In this article, we provide a knowledge-based system, capable of representing and reasoning about legal knowledge in the context of Answer Set Programming - thus, modelling non-monotonicity that is inherent in legal arguments. The work, although limited to a specific indicative domain, namely, university regulations, has a variety of extensions. The overall approach constitutes a representative implementation of the Answer Set Programming's modelling methodology, as well as an enhancing of the bond between Artificial Intelligence and Legal Science, bringing us a step closer to a successful development of an automated legal reasoning system for real-world applications.

This article analyses arguments used in an 1866 Brazilian freedom suit to highlight a substantive legal perspective. Historians of Brazilian slavery law have given attention to the politics of freedom suits, largely disregarding the role of law in their origins, developments, and outcomes. By looking at legal arguments, we show how law and political views mutually framed each other. We focus on the impact of 19th century legal modernizations in the distinction and contradictions between the law of status and property law, the legal translations of freedom, and the uses of arguments based on codes, natural law, and pragmatic considerations about the judiciary's role in a slave society. This is a micro-history of a suit that, with the help of other 19th-century freedom suits and legal doctrine, allows us to move up and down different historical scales to understand law's centrality in the political perpetuation and demise of slavery in Brazil.

This article is a defence of conservative legal argumentation and hopes to add a dimension of realism to the debate on Internet regulation. A recognition of the law`s inherent resistance to anything but incremental change, born out of its function to provide certainty and stability, must inform legal argumentation in particular in relation to legal issues arising out of a phenomenon as revolutionary as the Internet. By taking a bird`s eye perspective on the arguments on the issue of whether a website is enough to assert jurisdiction over the entity behind the website, the author argues that the most efficient regulatory options are not in fact the best or realistic regulatory options if their implementation entails substantial legal disruption. Legal adjustments to accommodate new technological phenomena such as the Internet often need not be as drastic, as may appear at first sight, if the relationship between law and the marketplace or law and technological developments is properly evaluated as two way.