Incorporating Legal Structure in Retrieval-Augmented Generation: A Case Study on Copyright Fair Use
Justin Ho, Alexandra Colby, William Fisher
TL;DR
This work tackles the problem of unreliable, text-only retrieval in legal AI applied to the Fair Use Doctrine under DMCA takedown contexts. It introduces a structured Retrieval-Augmented Generation framework that combines semantic search with a knowledge graph of legal precedents, court hierarchies, and factor-level content, augmented by citation networks and Chain-of-Thought reasoning. A functioning Neo4j-based prototype demonstrates that incorporating legal structure improves doctrinal relevance (as measured by PageRank-derived authority) at the expense of raw textual similarity, highlighting a trade-off between law-focused grounding and surface similarity. While promising, the approach requires rigorous evaluation, time-aware authority measures, and extension to other legal doctrines to enhance accessibility and reliability of automated legal assistance.
Abstract
This paper presents a domain-specific implementation of Retrieval-Augmented Generation (RAG) tailored to the Fair Use Doctrine in U.S. copyright law. Motivated by the increasing prevalence of DMCA takedowns and the lack of accessible legal support for content creators, we propose a structured approach that combines semantic search with legal knowledge graphs and court citation networks to improve retrieval quality and reasoning reliability. Our prototype models legal precedents at the statutory factor level (e.g., purpose, nature, amount, market effect) and incorporates citation-weighted graph representations to prioritize doctrinally authoritative sources. We use Chain-of-Thought reasoning and interleaved retrieval steps to better emulate legal reasoning. Preliminary testing suggests this method improves doctrinal relevance in the retrieval process, laying groundwork for future evaluation and deployment of LLM-based legal assistance tools.
