Large Legal Fictions: Profiling Legal Hallucinations in Large Language Models

Matthew Dahl, Varun Magesh, Mirac Suzgun, Daniel E. Ho

Journal of Legal Analysis 16(1), 64–93

What it adds

Separates externally checkable answers from contradiction-based hallucination estimates.

Read with this limitation

Contradiction-based estimates are lower bounds; federal-case sampling and historical models do not represent all legal practice.

Jurisdiction tags
United States
Language
English

Follow the source

Selected statements located in the linked primary sources. These results have not been independently reproduced here.

  1. For sampled verifiable case questions, reported hallucination rates range from 58% for GPT-4 to 88% for Llama 2.

    1 Introduction
  2. Sampling draws 5,000 cases at each of three federal-court levels.

    4.1 Data
Entry status, source edition & rights
Index entry
Source-linked summary, prepared with agent assistance. Independent scholarly review is pending.
Archive admission
This bibliographic entry does not confer admission to the versioned archive.
Edition inspected
2401.01301v2
Reading coverage
Exact arXiv v2 main methods/results, Figures 1–2, sections 2–6 and artifact description; 80-page document including appendices not exhaustively audited.
Rights
External references only. Papers and research artifacts remain with their original hosts; their own terms apply.
Entry updated
2026-10-15

Source-linked summary · independent assessment pending.

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