{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T12:10:23Z","timestamp":1764850223349,"version":"3.46.0"},"reference-count":0,"publisher":"IOS Press","isbn-type":[{"value":"9781643686387","type":"electronic"}],"license":[{"start":{"date-parts":[[2025,12,2]],"date-time":"2025-12-02T00:00:00Z","timestamp":1764633600000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,12,2]]},"abstract":"<jats:p>Guiding principles (Leits\u00b4latze) are central to German jurisprudence, capturing the essence of judicial reasoning in concise, doctrinally precise statements. Unlike general case summaries, they distill normative reasoning and key legal holdings rather than recounting factual backgrounds or procedural details. This paper examines how large language models (LLMs) can automatically generate guiding principles from German court decisions, focusing on three dimensions: model choice and adaptation, prompting strategies, and evaluation methods. Comparing GPT-4o with LerLeoLM, a fine-tuned, domain-specific model, we find that GPT-4o outperforms even without fine-tuning, while lightweight tuning on only 100 cases yields the best results. Human\u2013LLM co-designed prompts further enhance quality, surpassing both expert-structured and self-generated prompts. Finally, we show that LLM-based evaluation aligns more closely with expert judgment than traditional metrics, establishing guiding principle generation as a distinct task in Legal NLP.<\/jats:p>","DOI":"10.3233\/faia251612","type":"book-chapter","created":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T12:05:33Z","timestamp":1764849933000},"source":"Crossref","is-referenced-by-count":0,"title":["From Court Decisions to Guiding Principles: Advancing Complex Legal Summarization with LLMs"],"prefix":"10.3233","author":[{"given":"May Myo","family":"Zin","sequence":"first","affiliation":[{"name":"Center for Juris-Informatics, ROIS-DS, Tokyo, Japan"}]},{"given":"Ken","family":"Satoh","sequence":"additional","affiliation":[{"name":"Center for Juris-Informatics, ROIS-DS, Tokyo, Japan"}]},{"given":"Georg","family":"Borges","sequence":"additional","affiliation":[{"name":"Institute of Legal Informatics, Saarland University, Saarbr\u00fccken, Germany"}]}],"member":"7437","container-title":["Frontiers in Artificial Intelligence and Applications","Legal Knowledge and Information Systems"],"original-title":[],"link":[{"URL":"https:\/\/ebooks.iospress.nl\/pdf\/doi\/10.3233\/FAIA251612","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T12:05:33Z","timestamp":1764849933000},"score":1,"resource":{"primary":{"URL":"https:\/\/ebooks.iospress.nl\/doi\/10.3233\/FAIA251612"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,12,2]]},"ISBN":["9781643686387"],"references-count":0,"URL":"https:\/\/doi.org\/10.3233\/faia251612","relation":{},"ISSN":["0922-6389","1879-8314"],"issn-type":[{"value":"0922-6389","type":"print"},{"value":"1879-8314","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,12,2]]}}}