Journal of Information, Law and Technology

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This example differs from the example in DiaLaw. Here the content of a Court decision was taken over, whereas in DiaLaw the arguments of the court were adduced but defeated by a counter-argument (the municipality was negligent). We do not say that one outcome is better than the other. Both outcomes are defensible, and just show another aspect of argumentation. It would have led to far astray to show an example in which the decision of the Court was criticised by arguments of expert lawyers (like the already mentioned tort specialist professor Van Maanen), but these discussions must be possible if teaching systems are built, e.g. based on either DiaLaw or CumulA or on a combination.

4.3 Opportunities of the Graphical Approach

The implementation of CumulA, illustrated above, can be used in legal education for training several types of argumentation skills:

  • Students are forced to make arguments in an explicit reason-conclusion structure. For instance, they become aware of the fact that the same statement can be used as the reason in an argument and as the conclusion of an argument.

  • Students see that assumptions are needed to justify conclusions and how justified reasons make their conclusion justified.

  • Students can practice the different ways of using legal rules (as warrants behind reason/conclusion-connections) and legal cases (as support for conclusions) in arguments.

  • Students experience how counterarguments can be used to defeat arguments, that were previously undefeated. They undergo the successive changes of status. The relation of counterarguments and argument-structure is also clarified.

  • Students get a feeling for the role of process in argumentation by the gradual construction of arguments and counterarguments, and by the occurrence of status changes.

In training these skills the graphical approach to the mediation of legal argument can be beneficial, e.g.:

  • The graphical lay-out gives direct insight in the reason-conclusion structure in a line of argumentation.

  • The graphical lay-out directly shows which arguments are counterarguments to other arguments.

  • The changes of statuses (e.g., from undefeated to defeated) are directly noticeable by graphical changes.

The graphical approach is not appropriate in all respects. For instance, it partly requires an unusual attitude towards argumentation. People do not necessarily think in graphical terms of explicit reason/conclusion-structures. The use and presentation of counteraguments is even less familiar. A more fundamental issue is the limitation of the graphical interface. A long line of argument can easily go 'off-screen' and result in a complex and hard to understand structure of statements, reason-arrows, and counterargument-structures.6 The ArguMed-system [Verheij 1998b] has been developed as a successor to the Argue!-system in an attempt to enhance the familiarity of the interface and the transparency of the underlying argumentation theory.7

5. Towards a Hybrid Approach

Verbally presenting arguments has a long tradition. The old Greeks already paid attention to argumentation, understandably in verbal style only, while focussing on the core element of current mediating systems: dialectic. One of the first graphical approaches, and yet still widely used in AI & Law, are the argument schemata by Toulmin [1958].

We have suggested how both the verbal and the graphical approach to the mediation of legal argument can be useful as tools in teaching legal argument. The verbal approach fits in nicely with legal practice. As a result, students can practice skills they need in their professional career. They are trained in choosing arguments with the right meaning and rhetorical power.

The graphical approach has the advantage that it can provide a clear overview of a line of argumentation at a glance. One easily 'gets the picture'. The graphical approach also forces to think of arguments in a new way, namely in terms of pictures.

An additional tool of DiaLaw that has been formally defined, but is not implemented yet is that the dialog history can be depicted by means of trees [Lodder, 1998]. By way of the dialog trees a good insight into the layered structure of the dialogs is provided. Implementing these trees could be a first step towards combining the verbal and graphical approaches.

We recommend that both the verbal and the graphical approach are combined in one system, in order to profit from the best of each. E.g., the system could provide means to switch between different presentations. In order to encourage students to use the system, a game-like element is essential. In a dialog game they can try to win by beating their opponent, e.g., by drawing a convincing argument.

We think that integrating systems such as Argue! and DiaLaw could lead to a good result. Obviously, a hybrid system does not have to be based on an integration of the systems described in this paper, and we hope that others take up the thread by realising a genuine hybrid system for the mediation of legal argument. The next step would then be to use and test the system in an educational environment.

6. Conclusion

In this paper opportunities of computer-mediated legal argument in education are suggested. Two approaches to the presentation of arguments, the verbal and the graphical, have been discussed. The DiaLaw system and the Argue! system have been described as examples. Although both approaches have their specific merits, we think that a combination of the two would be most promising in an educational environment. We recommend that future research on automated tools for teaching legal arguments focuses on developing systems in which arguments are presented both graphically and verbally. By the development of attractive systems, e.g., with a game element, students can be encouraged to train their argumentation skills. Since training in these skills does often not receive much attention in the overloaded curricula of legal education, computer-mediated legal argument could become a valuable addition to argumentation courses in legal education.


Aarnio, A., Alexy, R., and Peczenik, A. (1981). The foundation of legal reasoning. Rechtstheorie 21, pp. 133‑158, 257-278, 423-448.

Aleven, V., and Ashley, K.D. (1997). Evaluating a Learning Environment for Case-Based Argumentation Skills. The Sixth International Conference on Artificial Intelligence and Law. Proceedings of the Conference, pp. 170-179. ACM, New York (New York).

Bench-Capon, T. (1995). Argument in Artificial Intelligence and Law, in: J.C. Hage et al. (eds.), Legal Knowledge Based Systems: Telecommunication and AI and Law, JURIX ‘95, Kloninklijke Vermande, Lelystad.

Bench-Capon, T.J.M., Leng, P.H., and Staniford, G. (1998). A Computer Supported Environment for the Teaching of Legal Argument. The Journal of Information, Law and Technology (JILT), 1998 (3), .

Centinia, F., Routen, T., Hartmann, A., and Hegarty, C. (1995). STATUTOR: Too intelligent by half? Legal knowledge based systems JURIX ’95: Telecommunication and AI & Law (eds. J.C. Hage, T.J.M. Bench-Capon, M.J. Cohen, and H.J. van den Herik), pp. 121-132. Koninklijke Vermande, Lelystad.

Dung, P.M. (1995). On the acceptability of arguments and its fundamental role in nonmonotonic reasoning, logic programming and n-person games. Artificial Intelligence, Vol. 77, pp. 321-357.

Eemeren, F.H. van, Grootendorst, R., and Kruiger, T. (1981). Argumentatietheorie. Uitgeverij Het Spectrum, Utrecht.

Eemeren, F.H. van, Grootendorst, R. and Kruiger, T. (1987). Handbook of Argumentation Theory. A Critical Survey of Classical Backgrounds and Modern Studies. Foris Publications, Dordrecht. Translation of van Eemeren et al. (1981).

Farley, A.M. and Freeman, K. (1995). Burden of Proof in Legal Argumentation, Proceedings of the Fifth International Conference on Artificial Intelligence and Law, ACM, New York, pp.156-164.

Fernhout, F.J., Cohen, M.J., Crombag, H.F.M., Pinckaers , R., and Temme, W. (1987). OBLIGATIO: computer simulation of legal cases. Leren studeren in het hoger onderwijs, pp. 204-209. Almere.

Gordon, T.F. (1993). The Pleadings Game - Formalizing Procedual Justice, Proceedings of the Fourth International Conference on Artificial Intelligence and Law, ACM, New York.

Gordon, T.F. (1995). The Pleadings Game - An artificial Intelligence Model of Procedural Justice. Kluwer, Dordrecht.

Habermas, J. (1973). Wahrheitstheorien. Wirklichkeit und Reflexion, Festschrift f. W. Schulz, pp. 211-265. H. Fahrenbach, Pfüllingen.

Hage, J. (1993). Monological reason based logic. A low level integration of rule-based reasoning and case-based reasoning. The Fourth International Conference on Artificial Intelligence and Law. Proceedings of the Conference, pp. 30-39. ACM, New York (New York). Also published as report SKBS/B3.A/93-08.

Hage, J. (1996). A Theory of Legal Reasoning and a Logic to Match. Artificial Intelligence and Law, Vol. 4, pp. 199-273.

Hage, J. (1997). Reasoning with Rules. An Essay on Legal Reasoning and Its Underlying Logic. Kluwer Academic Publishers, Dordrecht.

Hage, J, Leenes, R. and Lodder, A.R. (1994). Hard cases: a procedural approach. Artificial Intelligence and Law 2: 113-167.

Kowalski, R. and Toni, F. (1996). Abstract Argumentation. Artificial Intelligence and Law, Vol. 4, pp.275‑296.

Lodder, A.R., and Herczog, A. (1995). DiaLaw - A dialogical framework for modeling legal reasoning. The Fifth International Conference on Artificial Intelligence and Law. Proceedings of the Conference, pp. 146-155. ACM, New York (New York).

Lodder, A.R. (1996). Legal debate as an educational tool. Verso un sistema esperto giuridico integrale/Towards a global expert system in law, Tomo II (eds. C. Ciampi, F. Socci Natali & G. Taddei Elmi), pp. 129-138. CEDAM, Padova.

Lodder, A.R. (1998). DiaLaw – on legal justification and dialog games. Dissertation, Universiteit Maastricht.

Lodder, A.R., and Verheij, B. (1998). Opportunities of computer-mediated legal argument in education. Proceedings of the BILETA-conference – March 27-28. Dublin, Ireland.

Loui, R.P. (1991). Ampliative Inference, Computation, and Dialectic. Philosophy and AI. Essays at the Interface (eds. R. Cummins and J. Pollock), pp. 141-155. The MIT Press, Cambridge (Massachusetts).

Loui, R.P. (1992). Process and Policy: Resource-Bounded Non-Demonstrative Reasoning. Report WUCS-92-43. Washington University, Department of Computer Science, Saint Louis (Missouri).

Loui, R.P., Norman, J., Altepeter, J., Pinkard, D., Craven, D., Lindsay, J., and Foltz, M. (1997). Progress on Room 5. A Testbed for Public Interactive Semi-Formal Legal Argumentation. The Sixth International Conference on Artificial Intelligence and Law. Proceedings of the Conference, pp. 207-214. ACM, New York (New York).

Loui, R.P., Norman, J., Olson, J., and Merill, A. (1993). A Design for Reasoning with Policies, Precedents and Rationales, Proceedings of the Fourth International Conference on Artificial Intelligence and Law, ACM, New York, pp. 202-211.

Muntjewerff, A., and Groothuismink, J. (1998). PROSA. A Computer Program as Instructional Environment for Supporting the Learning of Legal Case Solving. Legal Knowledge-based Systems. JURIX: The Eleventh Conference (eds. J.C. Hage, T.J.M. Bench-Capon, A.W. Koers, C.N.J. de Vey Mestdagh, and C.A.F.M. Grütters), pp. 85-100. GNI, Nijmegen.

Nitta, K., and Shibasaki, M. (1997). Defeasible reasoning in Japanese criminal jurisprudence. Artificial Intelligence and Law, Vol 5, pp. 139-159.

Perelman, Ch., and Olbrechts-Tyteca, L. (1971). (Original French version in 1958). The New Rhetoric. A Treatise on Argumentation. University of Notre Dame Press, London.

Pollock, J.L. (1987). Defeasible reasoning. Cognitive Science, Vol. 11, pp. 481-518.

Pollock, J.L. (1995). Cognitive Carpentry: A Blueprint for How to Build a Person. The MIT Press, Cambridge (Massachusetts).

Prakken, H. and Sartor, G. (1996). A dialectical model of assessing in conflicting arguments in legal reasoning. Artificial Intelligence and Law, Vol. 4, pp. 331-368.

Routen, T. (1991). Complex Input: A Practical Way of Increasing the Bandwidth for Feedback and Student Modelling in a Statute-Based Tutoring System. The Third International Conference on Artificial Intelligence and Law. Proceedings of the Conference, pp. 77-80. ACM, New York (New York).

Searle, J.R. (1969). Speech acts: an essay in the philosophy of language. Cambridge university press.

Span, G. (1994). LITES: an Intelligent Tutoring System Shell for Legal Education. International Yearbook of Law Computers and Technology, Vol. 8, pp. 103-113.

Toulmin, S.E. (1958). The uses of argument. University Press, Cambridge.

Verheij, B. (1996). Rules, Reasons, Arguments. Formal studies of argumentation and defeat. Dissertation Universiteit Maastricht. A summary and table of contents are available on the World-Wide Web at .

Verheij, B. (1998a). Argue! - an implemented system for computer-mediated defeasible argumentation. NAIC '98. Proceedings of the Tenth Netherlands/Belgium Conference on Artificial Intelligence (eds. Han La Poutré and Jaap van den Herik), pp. 57-66. CWI, Amsterdam.

Verheij, B. (1998b). ArguMed - A Template-Based Argument Mediation System for Lawyers. Legal Knowledge Based Systems. JURIX: The Eleventh Conference (eds. J.C.Hage, T.J.M. Bench-Capon, A.W. Koers, C.N.J. de Vey Mestdagh and C.A.F.M. Grütters), pp. 113-130. Gerard Noodt Instituut, Nijmegen.

Verheij, B., Hage, J., and Lodder, A.R. (1997). Logical tools for legal argument: a practical assessment in the domain of tort. The Sixth International Conference on Artificial Intelligence and Law. Proceedings of the Conference, pp. 243-249. ACM, New York (New York). An abstract is available on the World-Wide Web at .

Verheij, B., and Lodder, A.R. (1998). Computer-mediated legal argument: the verbal vs. the visual approach. Proceedings of the 2nd French-American Conference on Artificial Intelligence and Law – June 11-12. Nice, France.

Vreeswijk, G.A.W. (1993). Studies in defeasible argumentation. Doctoral thesis, Vrije Universiteit, Amsterdam.

Vreeswijk, G.A.W. (1997). Abstract argumentation systems. Artificial Intelligence, Vol. 90, pp. 225-279.


Freeman, K., and Farley, A.M. (1996). A Model of Argumentation and Its Application to Legal Reasoning. Artificial Intelligence and Law, Vol. 4, pp. 163-197.

Gordon, T.F., and Karacapilidis, N. (1997). The Zeno Argumentation Framework. The Sixth International Conference on Artificial Intelligence and Law. Proceedings of the Conference, pp. 10-18. ACM, New York (New York).

Loui, R.P., and Norman, J. (1995). Rationales and argument moves. Artificial Intelligence and Law, Vol. 3, pp. 159-189.

Moore, D.J. (1993). Dialogue games and computer aided learning. Doctoral dissertation, Leeds Metropolitan University.

Prakken, H. (1997). Logical Tools for Modelling Legal Argument. A Study of Defeasible Reasoning in Law. Kluwer Academic Publishers, Dordrecht.

Yoshino, H. (1995). The Systematization of Legal Meta-inference. The Fifth International Conference on Artificial Intelligence and Law. Proceedings of the Conference, pp. 266-275. ACM, New York (New York).


Thomas Gordon -

Arno R. Lodder -

Ronald P. Loui -

John L. Pollock -

Henry Prakken -

Bart Verheij -

Tarski's World -

The OSCAR project -

Room 5 -

The ZENO project -

Argue! and ArguMed -

Dutch National Programme Information Technology and Law (ITeR) -

ITeR project 01437112 -

1 See, e.g., the work of Freeman and Farley [1996], Gordon [1995], Hage [1996, 1997], Lodder and Herczog [1995], Loui and Norman [1995], Prakken [1997], Prakken and Sartor [1996], Verheij [1996], and Yoshino [1995]. Verheij, Hage and Lodder [1997] give an overview.

2 Supposedly, since most effort has been spent on theoretical research.

3 An example of a mediating system used for educational purposes taking the verbal approach is [Moore, 1993].

4 The HELIC-systems [Nitta & Shisabaki, 1997] aim to model argumentation between a human-player and a computer-player.

5 An example of a mediating system used for educational purposes taking the graphical approach is Statutor [Routen 1991; Centinia et al., 1995].

6 Loui et al. [1997] provide a partial solution to this problem of ‘pointer spaghetti’. Instead of using arrows to connect reasons and conclusions, they use boxes inside other boxes.

7 See Verheij's web site on automated argument assistance .

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