Appeal to Expert Testimony – A Bayesian Approach

  • Christian Dahlman
  • Lena Wahlberg
Part of the Law and Philosophy Library book series (LAPS, volume 112)


In this chapter, we offer a Bayesian model for evaluating expert testimony in the court room. Statements from a putative expert are difficult for a legal decision maker to assess, as the legal decision maker – who lacks expert knowledge on the subject issue – must distinguish between experts that are highly reliable and experts that are less reliable. A methodology for the assessment of the expert testimony has been suggested previously, in the works of Walton and Goldman, and we develop this methodology further, using a Bayesian approach to reliability assessment. The reliability of an expert can be questioned on different grounds (lack of competence, bias and lack of motivation), and we clarify different effects that these grounds can have on the expert’s reliability.


Likelihood Ratio Expert Knowledge Expert Testimony Expert Witness Subject Issue 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Research financed by the Swedish Research Council (Vetenskapsrådet) and Ragnar Söderbergs Stiftelse. Thanks to Thomas Bustamte, Roberta Colonna Dahlman, Ulrike Hahn, Farhan Sarwar and Frank Zenker.


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Faculty of LawLund UniversityLundSweden
  2. 2.Lund UniversityLundSweden

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