How Does NLP Benefit Legal System: A Summary of Legal Artificial Intelligence

Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics, pages 5218–5230 July 5 - 10, 2020. c⃝2020 Association for Computational Linguistics 5218 How Does NLP Benefit Legal System: A Summary of Legal Artificial Intelligence Haoxi Zhong1, Chaojun Xiao1, Cunchao Tu1, Tianyang Zhang2, Zhiyuan Liu1∗, Maosong Sun1 1Department of Computer Science and Technology Institute for Artificial Intelligence, Tsinghua University, Beijing, China Beijing National Research Center for Information Science and Technology, China 2Beijing Powerlaw Intelligent Technology Co., Ltd., China zhonghaoxi@yeah.net, {xcjthu,tucunchao}@gmail.com, zty@powerlaw.ai, {lzy,sms}@tsinghua.edu.cn Abstract Legal Artificial Intelligence (LegalAI) focuses on applying the technology of artificial intelli- gence, especially natural language processing, to benefit tasks in the legal domain. In recent years, LegalAI has drawn increasing attention rapidly from both AI researchers and legal pro- fessionals, as LegalAI is beneficial to the legal system for liberating legal professionals from a maze of paperwork. Legal professionals of- ten think about how to solve tasks from rule- based and symbol-based methods, while NLP researchers concentrate more on data-driven and embedding methods. In this paper, we de- scribe the history, the current state, and the fu- ture directions of research in LegalAI. We il- lustrate the tasks from the perspectives of legal professionals and NLP researchers and show several representative applications in LegalAI. We conduct experiments and provide an in- depth analysis of the advantages and disadvan- tages of existing works to explore possible fu- ture directions. You can find the implemen- tation of our work from https://github. com/thunlp/CLAIM. 1 Introduction Legal Artificial Intelligence (LegalAI) mainly fo- cuses on applying artificial intelligence technology to help legal tasks. The majority of the resources in this field are presented in text forms, such as judgment documents, contracts, and legal opinions. Therefore, most LegalAI tasks are based on Natural Language Processing (NLP) technologies. LegalAI plays a significant role in the legal do- main, as they can reduce heavy and redundant work for legal professionals. Many tasks in the legal do- main require the expertise of legal practitioners and a thorough understanding of various legal doc- uments. Retrieving and understanding legal docu- ments take lots of time, even for legal professionals. ∗Corresponding author. Therefore, a qualified system of LegalAI should reduce the time consumption of these tedious jobs and benefit the legal system. Besides, LegalAI can also provide a reliable reference to those who are not familiar with the legal domain, serving as an affordable form of legal aid. In order to promote the development of LegalAI, many researchers have devoted considerable efforts over the past few decades. Early works (Kort, 1957; Ulmer, 1963; Nagel, 1963; Segal, 1984; Gardner, 1984) always use hand-crafted rules or features due to computational limitations at the time. In recent years, with rapid developments in deep learning, re- searchers begin to apply deep learning techniques to LegalAI. Several new LegalAI datasets have been proposed (Kano et al., 2018; Xiao et al., 2018; Duan et al., 2019; Chalkidis et al., 2019b,a), which can serve as benchmarks for research in the field. Based on …

Content truncated to 500 words