Preventing Miscarriages of Justice

Can judges learn to use Bayes’ rule, scenario theory and causal Bayesian Networks in the evaluation of evidence?

Over the last 20 years, wrongful convictions - such as Lucia de Berk (the Netherlands), Sally Clark (the United Kingdom) and Thomas Quick (Sweden) - have raised serious concerns about errors that judges make in the evaluation of evidence. This has fueled academic and societal debate on how judges and other legal factfinders can learn to reason more rationally about evidence in criminal cases.

Currently, the two main theoretical approaches to rational reasoning about legal evidence are the Bayesian probabilistic approach and the causal-explanatory approach. The Bayesian probabilistic approach is formal and offers a precise standard to evaluate evidence, but is difficult for lawyers to understand and apply correctly. The causal explanatory approach is easier to understand and to apply, but is informal and less precise. This project investigates how the two approaches can be integrated into a method that is both rigorous and practically feasible.

‘Preventing Miscarriages of Justice’ aims to improve judicial evidential decision-making by:

1. offering a theoretical analysis of how the two approaches can be integrated
2. developing an integrated training method for judges, with an open access handbook, tutorials and case studies and
3. empirically testing whether this training method helps judges to reason more rationally about evidence.

The project leaders are Anne Ruth Mackor (Groningen), Christian Dahlman (Lund) and Dave Lagnado (UCL). Postdocs collaborating on this project are Hylke Jellema and Moa Liden. Also contributing are PhD student Gustaf Svereus and student assistant Thomas Boersma. Affiliated researchers are Elaine Strittmatter (Zurich), Steven Hartkamp (Groningen) and Henry Prakken (Utrecht).

Duration of the project

2023 - 2028

Awarded grant

771,457 euros, obtained from SSH Open Competition Law and Public administration 2021

Contact persons at our Faculty

Prof. mr. dr. A.R. (Anne Ruth) Mackor
Dr. mr. H. (Hylke) Jellema

Websites with additional information