58%
GPT-4 legal hallucination rateStanford HAI, Journal of Legal Analysis 2024+15pp
Accuracy boost from multi-agent debateDu et al., ICML 2024300+
Judges now require AI citation verificationPost Mata v. Avianca standing orders$31K
Sanctions for AI-fabricated citationsCombined across U.S. courts, 2023-2025