Bayesian decision theory can guide legal factfinding

• Autores: Mario Günther
• Localización: Quaestio facti. Revista internacional sobre razonamiento probatorio, ISSN-e 2604-6202, Nº. 11, 2026, págs. 181-198
• Idioma: inglés
• DOI: 10.33115/udg_bib/qf.i11.23280
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• Resumen

  • I argue that Bayesian decision theory can guide legal factfinding. I do so by offering an account of legal proof on which judges should minimize expected justice costs. My account entails a judge’s credence threshold for finding guilty and his prior credence of guilt. Hence, it can guide a judge in his decision based on the lawful evidence presented at trial—unlike the Bayesian model Mackor presents.

• Referencias bibliográficas
  • Blackstone, W. (1753). Commentaries on the Laws of England: In Four Books (Vol. 2). J.B. Lippincott.
  • Colyvan, M., Regan, H. M., & Ferson, S. (2001). Is it a crime to belong to a reference class. Journal of Political Philosophy, 9(2), 168–181.
  • Dahlman, C. (2018). Determining the base rate for guilt. Law, Probability and Risk, 17(1), 15–28.
  • Dahlman, C., & Kolflaath, E. (2021). The problem of the prior in criminal trials. In Philosophical Foundations of Evidence Law (pp. 287–300)....
  • Fenton, N., & Lagnado, D. (2021, September). Bayesianism: Objections and rebuttals. In Philosophical Foundations of Evidence Law. Oxford...
  • Fenton, N., Lagnado, D., Dahlman, C., & Neil, M. (2017). The opportunity prior: A simple and practical solution to the prior probability...
  • Franklin, J. (2011). The objective Bayesian conceptualisation of proof and reference class problems. Sydney Law Review, 33(3), 545–561.
  • Friedman, R. D. (2000). A presumption of innocence, not of even odds. Stanford Law Review, 52(4), 873–887.
  • Günther, M. (2024a). Epistemic sensitivity and evidence. Inquiry, 67(6), 1348–1366.
  • Günther, M. (2024b). Legal proof should be justified belief of guilt. Legal Theory, 30(3), 129–141.
  • Günther, M. (2024c). Probability of guilt. Canadian Journal of Philosophy, 54(3), 189–206.
  • Günther, M., & Friedrich, C. (2026). A Bayesian justification for the scenario approach to legal proof. Proceedings of the Workshop on...
  • Hájek, A. (2007). The reference class problem is your problem too. Synthese, 156(3), 563–585.
  • Jeffrey, R. C. (1983). The Logic of Decision (2nd ed.). University of Chicago Press.
  • Jellema, H. (2025). Standards of proof for future crimes and decision theory. Quaestio facti. International Journal on Evidential Legal Reasoning,...
  • Kaplan, J. (1968). Decision theory and the factfinding process. Stanford Law Review, 20(6), 1065–1092.
  • Kaye, D. H. (1980). Naked statistical evidence. The Yale Law Journal, 89(3), 601–611.
  • Kaye, D. H. (1982). The limits of the preponderance of the evidence standard: Justifiably naked statistical evidence and multiple causation....
  • Kaye, D. H. (1999). Clarifying the burden of persuasion: What Bayesian decision rules do and do not do. The International Journal of Evidence...
  • Laudan, L., & Saunders, H. D. (2009). Rethinking the criminal standard of proof: Seeking consensus about the utilities of trial outcomes....
  • Lillquist, E. (2002). Recasting reasonable doubt: Decision theory and the virtues of variability. UC Davis Law Review, 36, 85–197.
  • Lindley, D. V. (1977). Probability and the law. Journal of the Royal Statistical Society. Series D (The Statistician), 26(3), 203–220.
  • Mackor, A. R. (2026). Bayesian modelling of criminal cases as a whole: A philosophical reflection on Dutch case law. Quaestio facti. International...
  • Mackor, A. R., & Prakken, H. (2026). On reporting likelihood ratio’s of exhaustive and non-exhaustive hypotheses about rare events in...
  • Nance, D. A. (2016). The Burdens of Proof: Discriminatory Power, Weight of Evidence, and Tenacity of Belief. Cambridge University Press.
  • Posner, R. A. (1999). An economic approach to the law of evidence. Stanford Law Review, 51, 1477–1546.
  • Ramsey, F. P. (1926). Truth and probability. In R. Braithwaite (Ed.), The Foundations of Mathematics and Other Logical Essays (1999 electronic...
  • Redmayne, M. (2008). Exploring the proof paradoxes. Legal Theory, 14(4), 281–309.
  • Reichenbach, H. (1949). The Theory of Probability. University of California Press.
  • Ross, L. (2023). Criminal proof: Fixed or flexible? The Philosophical Quarterly, 73(4), 1077–1099.
  • Savage, L. J. (1972). The Foundations of Statistics (2nd rev. ed.). Wiley Publications in Statistics.
  • Stein, A. (1996). Judicial factfinding and the Bayesian method: The case for deeper scepticism about their combination. The International...
  • Tribe, L. H. (1971). Trial by mathematics: Precision and ritual in the legal process. Harvard Law Review, 84(6), 1329–1393.
  • von Neumann, J., & Morgenstern, O. (1944). Theory of Games and Economic Behavior. Princeton University Press.