Dissertations / Theses on the topic 'Legal expert systems'

Most legal expert systems to date have been purely rule-based. Case-based reasoning is a methodology for building legal expert systems whereby profiles of cases contained in a database, rather than specific legal rules, direct the outcomes of the system. Frame-based knowledge representation in legal expert systems involves the use of frames to represent legal knowledge. Case-based reasoning and frame-based knowledge representation offer significant advantages over purely rule-based legal expert systems in case-based law. These advantages are realizable by using the deep structure approach to knowledge representation. This involves searching beneath law at the doctrinal level for underlying fact patterns and structures which explain decisions in cases. This is demonstrated by the Malicious Prosecution Consultant, a legal expert system which operates in the domain of the tort of malicious prosecution. The Malicious Prosecution Consultant confirms the results of earlier research at The University of British Columbia, Faculty of Law that it is possible to build legal expert systems in unstructured areas of case-based law with relatively cheap commercially available expert system shells by using the deep structure approach to knowledge representation.
Law, Peter A. Allard School of
Graduate

Most legal expert systems attempt to implement complex models of legal reasoning. Yet the utility of a legal expert system lies not in the extent to which it simulates a lawyer's approach to a legal problem, but in the quality of its predictions and of its arguments. A complex model of legal reasoning is not necessary: a successful legal expert system can be based upon a simplified model of legal reasoning. ¶ Some researchers have based their systems upon a jurisprudential approach to the law, yet lawyers are patently able to operate without any jurisprudential insight. A useful legal expert system should be capable of producing advice similar to that which one might get from a lawyer, so it should operate at the same pragmatic level of abstraction as does a lawyer - not at the more philosophical level of jurisprudence. ¶ A legal expert system called SHYSTER has been developed to demonstrate that a useful legal expert system can be based upon a pragmatic approach to the law. SHYSTER has a simple representation structure which simplifies the problem of knowledge acquisition. Yet this structure is complex enough for SHYSTER to produce useful advice. ¶ SHYSTER is a case-based legal expert system (although it has been designed so that it can be linked with a rule-based system to form a hybrid legal expert system). Its advice is based upon an examination of, and an argument about, the similarities and differences between cases. SHYSTER attempts to model the way in which lawyers argue with cases, but it does not attempt to model the way in which lawyers decide which cases to use in those arguments. Instead, it employs statistical techniques to quantify the similarity between cases. It decides which cases to use in argument, and what prediction it will make, on the basis of that similarity measure. ¶ SHYSTER is of a general design: it provides advice in areas of case law that have been specified by a legal expert using a specification language. Four different, and disparate, areas of law have been specified for SHYSTER, and its operation has been tested in each of those legal domains. ¶ Testing of SHYSTER in these four domains indicates that it is exceptionally good at predicting results, and fairly good at choosing cases with which to construct its arguments. SHYSTER demonstrates the viability of a pragmatic approach to legal expert system design.

Bibliography: leaves 462-479. "... to provide a basis for understanding countertrade practices. In particular, however, it aims to provide assistance to trading parties to identify the problems associated with various forms of countertrade and to give them guidance in drafting countertrade contracts in the light of Australian law.".

The subject of this thesis is the use of Information Technology (IT) to assist in the resolution of cases that appear before the Family Law Court in Australia. IT is used to assist in two processes. The first process is the intelligent gathering and preparation of information for Family Law cases. The second process is the modeling of case-decisions by the Family Law Court. The first process is covered in this thesis and the second process is part of the Andrew Stranieri's doctorate research at La Trobe University. Legal Interaction Charts (LIC) are developed to model procedures a Family Law solicitor carries out when gathering information and preparing a case. Sequenced Event Charts (SEC) are developed to implement LICs on a computer.

Legal knowledge engineering methodology for epistemologically sound, large scale legal expert systems is developed in this dissertation. A specific meta-epistemological method is posed for the transformation of legal domain epistemology to large scale legal expert systems; the method has five stages: 1. domain epistemology; 2. computational domain epistemology; 3. shell epistemology; 4. programming epistemology; and 5. application epistemology and ontology. The nature of legal epistemology is defined in terms of a deep model that divides the information of the ontology of legal possibilities into the three sorts of logic premises, namely, (1) rules of law for extended deduction, (2) material facts of cases for induction that establishes rule antecedents, and (3) reasons for rules, including justifications, explanations or criticisms of rules, for abduction. Extended deduction is distinguished for automation, and provides a map for locating, relatively, associated induction and abduction. Added to this is a communication system that involves issues of cognition and justice in the legal system. The Appendix sets out a sample of draft rule maps of the United Nations Convention on Contracts for the International Sale of Goods, known as the Vienna Convention, to illustrate that the substantive epistemology of the international law can be mapped to the generic epistemology of the shell. This thesis deflects the ontological solution back to the earlier rule-based, case-based and logic advances, with a definition of artificial legal intelligence that rests on legal epistemology; added to the definition is a transparent communication system of a user interface, including an interactive visualisation of rule maps, and the heuristics that process input and produce output to give effect to the legal intelligence of an application. The additions include an epistemological use of the ontology of legal possibilities to complete legal logic, for the purposes of processing specific legal applications. While the specific meta-epistemological methodology distinguishes domain epistemology from the epistemologies of artificial legal intelligence, namely computational domain epistemology, program design epistemology, programming epistemology and application epistemology, the prototypes illustrate the use of those distinctions, and the synthesis effected by that use. The thesis develops the Jurisprudence of Legal Knowledge Engineering by an artificial metaphysics.
Doctor of Philosophy (Ph.D)

Legal knowledge engineering methodology for epistemologically sound, large scale legal expert systems is developed in this dissertation. A specific meta-epistemological method is posed for the transformation of legal domain epistemology to large scale legal expert systems; the method has five stages: 1. domain epistemology; 2. computational domain epistemology; 3. shell epistemology; 4. programming epistemology; and 5. application epistemology and ontology. The nature of legal epistemology is defined in terms of a deep model that divides the information of the ontology of legal possibilities into the three sorts of logic premises, namely, (1) rules of law for extended deduction, (2) material facts of cases for induction that establishes rule antecedents, and (3) reasons for rules, including justifications, explanations or criticisms of rules, for abduction. Extended deduction is distinguished for automation, and provides a map for locating, relatively, associated induction and abduction. Added to this is a communication system that involves issues of cognition and justice in the legal system. The Appendix sets out a sample of draft rule maps of the United Nations Convention on Contracts for the International Sale of Goods, known as the Vienna Convention, to illustrate that the substantive epistemology of the international law can be mapped to the generic epistemology of the shell. This thesis deflects the ontological solution back to the earlier rule-based, case-based and logic advances, with a definition of artificial legal intelligence that rests on legal epistemology; added to the definition is a transparent communication system of a user interface, including an interactive visualisation of rule maps, and the heuristics that process input and produce output to give effect to the legal intelligence of an application. The additions include an epistemological use of the ontology of legal possibilities to complete legal logic, for the purposes of processing specific legal applications. While the specific meta-epistemological methodology distinguishes domain epistemology from the epistemologies of artificial legal intelligence, namely computational domain epistemology, program design epistemology, programming epistemology and application epistemology, the prototypes illustrate the use of those distinctions, and the synthesis effected by that use. The thesis develops the Jurisprudence of Legal Knowledge Engineering by an artificial metaphysics.

This dissertation adopts an interdisciplinary approach to the field of law and artificial intelligence. It argues that the conceptual structuring of legal knowledge within an appropriate theoretical framework is of primary importance when building knowledge-based systems. While technical considerations also play a role, they must take second place to an in-depth understanding of the law. Two alternative methods of structuring legal knowledge in very different domains are used to explore the thesis. A deep-structure approach is used on nervous shock, a rather obscure area of the law of negligence. A script-based method is applied to impaired driving, a well-known part of the criminal law. A knowledge-based system is implemented in each area. The two systems, Nervous Shock Advisor (NSA) and Impaired Driving Advisor (IDA), and the methodologies they embody, are described and contrasted. In light of the work undertaken, consideration is given to the feasibility of lawyers without much technical knowledge using general-purpose tools to build knowledge-based systems for themselves.

Forensic science has a significant historical and contemporary relationship with the criminal justice system. It is a relationship between two disciplines whose origins stem from different backgrounds. It is trite that effective communication assist in resolving underlying problems in any given context. However, a lack of communication continues to characterise the intersection between law and science. As recently as 2019, a six-part symposium on the use of forensic science in the criminal justice system again posed the question on how the justice system could ensure the reliability of forensic science evidence presented during trials. As the law demands finality, science is always evolving and can never be considered finite or final. Legal systems do not always adapt to the nature of scientific knowledge, and are not willing to abandon finality when that scientific knowledge shifts. Advocacy plays an important role in the promotion of forensic science, particularly advocacy to the broader scientific community for financial support, much needed research and more testing. However, despite its important function, advocacy should not be conflated with science. The foundation of advocacy is a cause; whereas the foundation of science is fact. The objective of this research was to conduct a qualitative literature review of the field of forensic science; to identify gaps in the knowledge of forensic science and its integration in the criminal justice system. The literature review will provide researchers within the field of forensic science with suggested research topics requiring further examination and research. To achieve its objective, the study critically analysed the historical development of, and evaluated the use of forensic science evidence in legal systems generally, including its role regarding the admissibility or inadmissibility of the evidence in the courtroom. In conclusion, it was determined that the breadth of forensic scientific knowledge is comprehensive but scattered. The foundational underpinning of the four disciplines, discussed in this dissertation, has been put to the legal test on countless occasions. Some gaps still remain that require further research in order to strengthen the foundation of the disciplines. Human influence will always be present in examinations and interpretations and will lean towards subjective decision making.
Jurisprudence
D. Phil.

Legal expert systems are the nexus of Artificial Intelligence and the law. A legal expert system is "a system capable of performing at a level expected of a lawyer" [Popple 1996, page 3]. Legal expert systems may be designed for use by legally trained people or for use by the general public ("lay-people"). Legal expert systems designed for use by legally trained people aim to provide a method of speeding-up the provision, and improving the accuracy, of legal research undertaken with the aim of advising the client. Designed for use by legally trained people, these systems may assume general legal knowledge. Consequently the questions asked by the system and the reports returned may be stated at a level appropriate for legally trained people. The primary benefit of this category of legal expert system is the reduction of internal cost of legal research. The flow-on benefits for clients reductions in the cost of legal services and consequently improved access to quality representation, and reduction of the time taken to resolve a legal question. Legal expert systems designed for use by lay-people aim to provide greater access to the law. This category of legal expert system is more difficult to create because no legal knowledge by the user can be assumed. The discovery of the facts of the case becomes problematic [Susskind 2001]. More research is required in the area of fact elicitation before such systems become viable. Once they are viable, access to the law should be dramatically improved. A consequential benefit may be a reduction in litigation, as potential litigants could settle their dispute by reference to the advice of a legal expert system. However, such a system would raise an important ethical question -- the creators of such a system may be usurping the role of the courts in that the public may come to rely on the statements by the system as "what the law is". SHYSTER-MYCIN is the legal expert system created for and discussed in this thesis. SHYSTER-MYCIN combines rule-based reasoning with case-based reasoning. The system is designed as the first category of legal expert systems described above: a legal expert system to be consulted by legally trained people. This hybrid system enables the case-based reasoner to determine open-textured concepts when required by the rule-based reasoner, MYCIN. The system operates on a reduced version of the Copyright Act 1968, including cases that define the term "authorization" (see Chapter 2). The Act is reasoned by a system of rules. Whereas cases are reasoned by analogy. This approach is supported by jurisprudential discussions on legal reasoning (see Chapter 3). The system was created in three progressive versions (Chapter 5). The focus of the creation of the system was the reporting of reasons for conclusions. The second and third versions were tested against three criteria: validity, conciseness and correctness (see Chapter 6). The system performed well (see Chapter 7) against those criteria, indicating that the approach taken is appropriate: that is, it is appropriate to use rules to reason with statutes and analogy to reason with cases.

... A legal expert system called SHYSTER has been developed to demonstrate that a useful legal expert system can be based upon a pragmatic approach to the law. SHYSTER has a simple representation structure which simplifies the problem of knowledge acquisition. Yet this structure is complex enough for SHYSTER to produce useful advice. ¶ SHYSTER is a case-based legal expert system (although it has been designed so that it can be linked with a rule-based system to form a hybrid legal expert system). Its advice is based upon an examination of, and an argument about, the similarities and differences between cases. SHYSTER attempts to model the way in which lawyers argue with cases, but it does not attempt to model the way in which lawyers decide which cases to use in those arguments. Instead, it employs statistical techniques to quantify the similarity between cases. It decides which cases to use in argument, and what prediction it will make, on the basis of that similarity measure. ¶ SHYSTER is of a general design: it provides advice in areas of case law that have been specified by a legal expert using a specification language. Four different, and disparate, areas of law have been specified for SHYSTER, and its operation has been tested in each of those legal domains. ¶ Testing of SHYSTER in these four domains indicates that it is exceptionally good at predicting results, and fairly good at choosing cases with which to construct its arguments. SHYSTER demonstrates the viability of a pragmatic approach to legal expert system design.

Bibliography: leaves 462-479.
xx, 479 leaves ; 30 cm.
"... to provide a basis for understanding countertrade practices. In particular, however, it aims to provide assistance to trading parties to identify the problems associated with various forms of countertrade and to give them guidance in drafting countertrade contracts in the light of Australian law.".
Thesis (Ph.D.) -- University of Adelaide, Dept. of Law, 1998?

Bibliography: leaves 462-479.
xx, 479 leaves ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
"... to provide a basis for understanding countertrade practices. In particular, however, it aims to provide assistance to trading parties to identify the problems associated with various forms of countertrade and to give them guidance in drafting countertrade contracts in the light of Australian law.".
Thesis (Ph.D.)--University of Adelaide, Dept. of Law, 1998?