Artificial Intelligence and Law

, Volume 25, Issue 4, pp 397–428 | Cite as

Norm conflict identification in contracts

  • João Paulo Aires
  • Daniele PinheiroEmail author
  • Vera Strube de Lima
  • Felipe Meneguzzi
Original Research


The exchange of goods and services between individuals is often formalised by a contract in which the parties establish norms to define what is expected of each one. Norms use deontic statements of obligation, prohibition, and permission, which may be in conflict. The task of manually detecting norm conflicts can be time–consuming and error-prone since contracts can be vast and complex. To automate such tasks, we develop an approach to identify potential conflicts between norms. We show the effectiveness of our approach and its individual components empirically using two publicly available corpora, and contribute with a new annotated test corpus for norm conflict identification.


Norms Natural language processing Normative conflicts Deontic logic 



We would like to thank HP PROFCSI for funding our research. Felipe thanks CNPq for support within Grant Number 306864/2016-4 under the PQ fellowship project.


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Copyright information

© Springer Science+Business Media B.V. 2017

Authors and Affiliations

  1. 1.Porto AlegreBrazil

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