Causal-Audit: Explicit and Auditable Graph-based Reasoning via Target-Aware Causal Chain Construction

Su Lan, Xuefei Yin, Yanming Zhu, Alan Wee-Chung Liew


Abstract
Causal and intervention-based question answering is fundamental to advancing large language models (LLMs) toward reasoning beyond surface-level correlations and understanding underlying causal mechanisms. However, existing LLM-based methods often rely on implicit language-level reasoning, resulting in opaque causal assumptions, unverifiable reasoning paths, and fragile predictions under complex interventions, particularly in context-free settings. In this paper, we propose an explicit and auditable causal reasoning framework for context-free intervention-based question answering. Our method formulates causal inference as structured reasoning over an explicit causal graph through four modular stages, rather than implicit end-to-end prediction. A key innovation is a target-aware causal graph construction strategy that treats the target variable as a core constraint during graph expansion, effectively suppressing irrelevant variables, spurious causal relations, and reasoning noise. We further introduce a path-level causal evidence aggregation mechanism that combines multiple causal paths while modeling both reinforcing and counteracting effects, enabling robust decision-making beyond single-chain reasoning. Extensive experiments on three benchmarks demonstrate that our framework consistently outperforms existing LLM-based methods while providing interpretable and auditable causal reasoning traces.
Anthology ID:
2026.findings-acl.607
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
Findings
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Publisher:
Association for Computational Linguistics
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Pages:
12484–12500
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URL:
https://preview.aclanthology.org/ingest-acl/2026.findings-acl.607/
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Cite (ACL):
Su Lan, Xuefei Yin, Yanming Zhu, and Alan Wee-Chung Liew. 2026. Causal-Audit: Explicit and Auditable Graph-based Reasoning via Target-Aware Causal Chain Construction. In Findings of the Association for Computational Linguistics: ACL 2026, pages 12484–12500, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Causal-Audit: Explicit and Auditable Graph-based Reasoning via Target-Aware Causal Chain Construction (Lan et al., Findings 2026)
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.607.pdf
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