Assessing Large Language Models on Islamic Legal Reasoning: Evidence from Inheritance Law Evaluation

Abdessalam Bouchekif, Samer Rashwani, Heba Sbahi, Shahd Gaben, Mutaz Al Khatib, Mohammed Ghaly


Abstract
This paper evaluates the knowledge and reasoning capabilities of Large Language Models in Islamic inheritance law, ʿilm al-mawārīth. We assess the performance of seven LLMs using a benchmark of 1,000 multiple-choice questions covering diverse inheritance scenarios, designed to test each model’s ability—from understanding the inheritance context to computing the distribution of shares prescribed by Islamic jurisprudence. The results show a wide performance gap among models. o3 and Gemini 2.5 achieved accuracies above 90%, while ALLaM, Fanar, LLaMA, and Mistral scored below 50%. These disparities reflect important differences in reasoning ability and domain adaptation.We conduct a detailed error analysis to identify recurring failure patterns across models, including misunderstandings of inheritance scenarios, incorrect application of legal rules, and insufficient domain knowledge. Our findings highlight the limitations of current models in handling structured legal reasoning and suggest directions for improving their performance in Islamic legal reasoning.
Anthology ID:
2025.arabicnlp-main.20
Volume:
Proceedings of The Third Arabic Natural Language Processing Conference
Month:
November
Year:
2025
Address:
Suzhou, China
Editors:
Kareem Darwish, Ahmed Ali, Ibrahim Abu Farha, Samia Touileb, Imed Zitouni, Ahmed Abdelali, Sharefah Al-Ghamdi, Sakhar Alkhereyf, Wajdi Zaghouani, Salam Khalifa, Badr AlKhamissi, Rawan Almatham, Injy Hamed, Zaid Alyafeai, Areeb Alowisheq, Go Inoue, Khalil Mrini, Waad Alshammari
Venue:
ArabicNLP
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
246–257
Language:
URL:
https://preview.aclanthology.org/ingest-emnlp/2025.arabicnlp-main.20/
DOI:
Bibkey:
Cite (ACL):
Abdessalam Bouchekif, Samer Rashwani, Heba Sbahi, Shahd Gaben, Mutaz Al Khatib, and Mohammed Ghaly. 2025. Assessing Large Language Models on Islamic Legal Reasoning: Evidence from Inheritance Law Evaluation. In Proceedings of The Third Arabic Natural Language Processing Conference, pages 246–257, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
Assessing Large Language Models on Islamic Legal Reasoning: Evidence from Inheritance Law Evaluation (Bouchekif et al., ArabicNLP 2025)
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PDF:
https://preview.aclanthology.org/ingest-emnlp/2025.arabicnlp-main.20.pdf