Researchers funded by the Center for Statistics and Applications in Forensic Evidence (CSAFE) have developed a worksheet that forensic examiners can use to document their decision-making process and help reduce potential bias in their analyses. It is available online for free and can be tailored to any forensic discipline.
The worksheet and how to use it are explained in a paper published by Forensic Science International: Synergy. The lead author is CSAFE researcher Adele Quigley-McBride, a post-doctoral fellow at Duke University. Collaborators on the project included Itiel Dror, a researcher at the University College London; Tiffany Roy, president of ForensicAid; Brandon Garrett, CSAFE co-director and the L. Neil Williams, Jr. Professor of Law and director of the Wilson Center for Science and Justice at Duke University; and Jeff Kukucka, an associate professor of psychology at Towson University.
“Researchers often make suggestions about practices they believe could improve procedures in forensic laboratories, but these suggestions are rarely in a form that could be directly implemented in a laboratory,” said Quigley-McBride. “We wanted to provide a research-based tool that analysts could use right away to think through the potential sources of cognitive bias in their analyses and formulate plans to manage that information.”
The researchers designed the worksheet to help forensic labs implement an existing information management framework called Linear Sequential Unmasking-Expanded, or LSU-E for short. LSU-E was introduced in 2021 by Dror and Kukucka to help guide forensic labs’ evaluation of case information.
Examiners can use LSU-E to help determine what information to consider and in what order using three main criteria: biasing power, objectivity and relevance. Biasing power refers to the potential for the information to push an analyst towards a particular conclusion. For example, does the piece of information imply or suggest that a certain outcome is correct or best, and how strong is the implication or suggestion? The objectivity criterion requires examiners to consider whether a piece of information could support different interpretations or meanings. Finally, relevance is the degree to which any piece of information is essential to the analysis.
The worksheet walks an analyst through these considerations. There are three steps that forensic analysts are encouraged to follow when assessing new information. First, the piece of information and its source is documented. Second, the analyst considers each of the three LSU-E criteria, and the information is rated on a scale of 1-5 for each criterion. Finally, there is space for the user to describe any strategies used to minimize the adverse effects the information may have on the decision-making process.
Quigley-McBride said anything that is sent to or received by the lab alongside the evidence to be analyzed should be incorporated into the worksheet. That information could include documents, communications, eyewitness accounts, police reports, or anything else that would normally be given to the examiner, even if it is unlikely to contribute to cognitive bias.
“The level of detail will vary by case, type of information and forensic technique, but the worksheet was designed to accommodate a wide range of forensic disciplines and decisions,” Quigley-McBride said.
The worksheet should be adaptable to any lab’s standard operating procedure and can be used after a short training session. To help implement the worksheet, the authors have developed training materials and provided examples based on different forensic disciplines, including how to rate and consider different types of information.
Quigley-McBride said that ideally, the worksheet would be filled out by someone other than the person analyzing the evidence to help prevent the examiner from seeing information with a high potential to bias conclusions. That said, the worksheet would also be effective when used by each analyst as part of their workflow.
The worksheet will help analysts make better decisions with the information they have access to and provides a way to document that process, Quigley-McBride said. Encouraging transparency in forensic decision-making will increase public confidence in forensic science and protect analysts who use information management procedures, she said.
“We hope to partner with labs to get feedback on how effective the tool is when incorporated into a lab’s workflow. We encourage interested labs to contact us whether they are seeking support as they work to implement this tool or they wish to take part in the initial testing of the tool,” Quigley-McBride said.
Download the journal article and read insights from this study at https://forensicstats.org/blog/2022/02/05/insights-a-practical-tool-for-information-management-in-forensic-decisions/.
The LSU-E worksheet and training materials can be viewed and downloaded on the Open Science Framework at https://osf.io/xm3ru/.
Learn more about Linear Sequential Unmasking-Expanded (LSU-E). Itiel Dror discussed LSU-E during the CSAFE-hosted webinar, Improving Forensic Decision Making: A Human-Cognitive Perspective. Watch it at https://forensicstats.org/blog/portfolio/improving-forensic-decision-making/.
