Abstract
Legal question answering is an important natural language processing application in the legal domain. The Judicial Examination of Chinese Question Answering dataset is the most prominent and more challenging legal question answering dataset, which offers many multiple-choice legal questions and meta-information about the questions labelled by skilled humans. The current approaches to this task rely solely on pre-trained language models and do not find effective ways to utilise legal knowledge. We propose a retrieving-then-answering framework for the task. Its core is the Graph-Based Evidence Retrieval and Aggregation Network. The network enhances the model’s ability to answer a question by leveraging the legal knowledge relevant to the question and its answer options. The experimental results show that our model outperforms the existing state-of-the-art methods. The results also indicate that our proposed approach to using evidence is practical.






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The JEC-QA dataset used in the current study are available at https://jecqa.thunlp.org.
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Acknowledgements
We want to extend our heartfelt gratitude to the anonymous reviewers for their insightful comments and constructive suggestions. Their expertise and dedication to the peer review process have significantly contributed to enhancing the quality and rigour of this manuscript. Their input was invaluable in refining our paper to its current form. We sincerely appreciate their time and effort. Also, we would like to extend our heartfelt gratitude to Guibin Chen, whose invaluable insights and diligent efforts have played a critical role in refining this paper. His expertise and guidance have been a beacon of light in enhancing this manuscript. This manuscript is an extended version of our prior work [52]. This work was supported by the National Natural Science Foundation of China (No. 61762016), the Middle-aged and Young Teachers’ Basic Ability Promotion Project of Guangxi(No. 2021KY0067) and Research Fund of Guangxi Key Lab of Multi-source Information Mining & Security (22-A-01-02).
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Li, Y., Wu, J. & Luo, X. BERT-CNN based evidence retrieval and aggregation for Chinese legal multi-choice question answering. Neural Comput & Applic 36, 5909–5925 (2024). https://doi.org/10.1007/s00521-023-09380-5
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DOI: https://doi.org/10.1007/s00521-023-09380-5