H-LegalKI: A Hierarchical Legal Knowledge Integration Framework for Legal Community Question Answering

Yue Jiang, Ziyu Guan, Jie Zhao, Wei Zhao, Jiaqi Yang


Abstract
Legal question answering (LQA) aims to bridge the gap between the limited availability of legal professionals and the high demand for legal assistance. Traditional LQA approaches typically either select the optimal answers from an answer set or extract answers from law texts. However, they often struggle to provide relevant answers to complex, real-world questions due to the rigidity of predetermined answers. Although recent advancements in legal large language models have shown some potential in enhancing answer relevance, they fail to address the multiple user-specific circumstances, i.e., factual details in questions. To address these issues, we (1) construct the first publicly available legal community question-answering (LegalCQA) dataset; and (2) propose a Hierarchical Legal Knowledge Integration (H-LegalKI) framework. LegalCQA is collected from two widely used legal forums for developing user-centered LQA models. For H-LegalKI, we design a legal knowledge retriever that gathers comprehensive legal knowledge based on both entire questions and individual sentences. And an answer generation model is designed to understand question- and sentence-level factual details and integrate corresponding legal knowledge in a hierarchical way. Additionally, we design a de-redundancy module to remove redundant legal knowledge. Experiments on LegalCQA demonstrate the superiority of our framework over competitive baselines.
Anthology ID:
2024.findings-emnlp.856
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2024
Month:
November
Year:
2024
Address:
Miami, Florida, USA
Editors:
Yaser Al-Onaizan, Mohit Bansal, Yun-Nung Chen
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
14614–14625
Language:
URL:
https://aclanthology.org/2024.findings-emnlp.856
DOI:
10.18653/v1/2024.findings-emnlp.856
Bibkey:
Cite (ACL):
Yue Jiang, Ziyu Guan, Jie Zhao, Wei Zhao, and Jiaqi Yang. 2024. H-LegalKI: A Hierarchical Legal Knowledge Integration Framework for Legal Community Question Answering. In Findings of the Association for Computational Linguistics: EMNLP 2024, pages 14614–14625, Miami, Florida, USA. Association for Computational Linguistics.
Cite (Informal):
H-LegalKI: A Hierarchical Legal Knowledge Integration Framework for Legal Community Question Answering (Jiang et al., Findings 2024)
Copy Citation:
PDF:
https://aclanthology.org/2024.findings-emnlp.856.pdf