Challenges and future directions in studying sequencing as a debiasing strategy in forensic psychological assessment: A commentary on Kukucka and Quigley-McBride (2025)

Abstract

In 1979, Kahneman and Tversky showed that human information processing is subject to bias. They identified a number of factors, such as the order in which information is presented, that systematically lead people to make decisions that are not rational. In 2020, an international group of researchers tested N = 4099 participants from 19 countries and 13 languages and found that 94% of Kahneman and Tversky's (1979) findings were replicated (Ruggeri et al., 2020). This makes the evidence for human susceptibility to bias one of the most replicated findings in psychology, and one in urgent need of remedy.

Intuitively, the most effective way to avoid being biased by certain information is to not have that information. This technique is called masking (or blinding) and inspired the debiasing approach Linear Sequencing Unmasking-Expanded (LSU-E, Dror & Kukucka, 2021). The LSU-E approach is based on empirically verified principles and has been applied to several forensic sciences, including the detection of deep-fake images (Casu et al., 2024) or the identification of victims (Dahal et al., 2022). Against this background, LSU-E is a promising approach for reducing bias in forensic psychological assessments. In an initial study, we tested whether a core factor, that is the sequencing of case information, was effective in reducing bias in criminal risk assessment as an exemplary area of forensic psychological assessment (Oberlader & Verschuere, 2024a).

In their commentary on our article ‘Bias is persistent: Sequencing case information does not protect against contextual bias in criminal risk assessment’ (Oberlader & Verschuere, 2024a), Kukucka and Quigley-McBride (2025) critically assessed the validity of our study. The authors warned that our results and interpretations may give an overly pessimistic picture of the effectiveness of the debiasing approach LSU-E (Dror & Kukucka, 2021). Here, we first address what we consider to be their main criticisms of our study and then suggest future avenues for investigating the effectiveness of this promising debiasing method.

In a preregistered experimental study with 308 informed lay participants, we investigated whether the presentation of irrelevant case information biases criminal risk assessment based on an actuarial-empirical risk assessment tool. We supposed that participants' criminal risk assessment in a fictitious case would be closer to the result of an actuarial-empirical risk assessment tool, and thus less biased, if they were given only relevant case information than if they were additionally given irrelevant case information. Case information was defined as relevant if it was necessary for the application of the actuarial-empirical risk assessment tool, and as irrelevant if it was not.

Critically, we also tested whether this bias could be reduced by presenting irrelevant case information after, rather than before, the application of an actuarial-empirical risk assessment tool. We supposed that sequencing case information could prevent the actuarial-empirical risk assessment tool itself from being biased by irrelevant information, thus reducing the influence of this information on the final judgment of the offender's risk of reoffending.

The participants' criminal risk assessments were indeed biased by the irrelevant case information. Unfortunately, sequencing did not reduce this bias. Participants were equally biased regardless of whether the irrelevant case information was presented after, rather than before, the use of the actuarial-empirical risk assessment tool. Kukucka and Quigley-McBride (2025) voiced several concerns about our study, which we address in the following three sections.

‘Information hygiene’—controlling the sequence and nature of the processed information—can help to avoid bias (Oberlader et al., 2025), and we highly welcome the LSU-E for providing a framework for dealing with potentially biasing information. To reduce bias, experts should only receive the information they need for a particular step in the assessment. All other information should be kept away from them for as long as possible. Although this idea seems simple at first glance, our initial study shows that it poses challenges for implementation in forensic psychological assessment. These challenges may inspire which elements of LSU-E may be helpful in debiasing forensic psychological assessment, and under what conditions the LSU-E approach may work in forensic psychological assessment.

First, it is important to consider that the LSU-E approach includes other elements in addition to the sequencing of case information (e.g. documenting changes in assessments as new case information is coming in), and future studies should evaluate these components as well as the integral application of LSU-E for forensic psychological assessment. Moreover, these studies could assess their presumed benefits other than minimizing bias, such as increased transparency (Dror & Kukucka, 2021). Second, future research should focus on capturing the psychological processes that take place during the assessment process to understand why the LSU-E approach does (not) work (e.g. how the relevance of case information is assessed; the extent to which experts trust different sources of information). Such processes could, for example, be investigated in think-aloud studies (Someren et al., 1994). Third, to increase the ecological validity of study results, it would of course be important to consider a sample of experts rather than informed laypeople. Although there are many similarities between different areas of forensic psychological assessment, it is important to examine the effectiveness of the LSU-E approach in relation to other legal issues, such as credibility assessment, in order to test its generalisability or specific boundary conditions (Oberlader & Verschuere, 2024b).

Since we know that bias is not only inherent in human information processing but also very persistent, scientists should be equally persistent in finding ways to make forensic psychological assessment as objective and fair as possible. Numerous approaches have been discussed in the recent past (e.g. Neal et al., 2022; Oberlader et al., 2025; Vredeveldt et al., 2022). Now we need to thoroughly test them.

Verena Oberlader: Conceptualization; writing – original draft. Bruno Verschuere: Conceptualization; writing – review and editing.

The authors declare no conflicts of interest.