Semantics of Subterfuge: Benchmarking Legal Deception Detection Against General-domain State-of-the-Art

Abstract:Deception detection has critical implications for legal proceedings, law enforcement, and online security. Although human judgment is limited in accuracy and scalability, Natural Language Processing (NLP) offers a data-driven alternative. We present a survey and comparative analysis of NLP-based Automatic Deception Detection (ADD) focusing on the legal domain, reviewing the evolution from feature-based machine learning to Large Language Model (LLM) approaches. We conduct a unified empirical evaluation across seven datasets (two legal, five general-domain), comparing six fine-tuned transformer models and seven LLMs under four prompting strategies. The results show strong domain sensitivity, with fine-tuned models excelling in data-rich general domains and few-shot LLMs remaining competitive in low-resource legal settings. Chain-of-Thought prompting often underperforms direct classification. These findings highlight the need for domain adaptation and interpretable systems in high-stakes legal contexts.

Computation and Language (cs.CL); Artificial Intelligence (cs.AI)

arXiv:2607.29066 [cs.CL]

(or arXiv:2607.29066v1 [cs.CL] for this version)

https://doi.org/10.48550/arXiv.2607.29066 Focus to learn more arXiv-issued DOI via DataCite (pending registration)

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