The Starbuck Case: Methods for addressing confirmation bias in forensic authorship analysis.

Abstract

Nearly two years previously, Debbie married Jamie Starbuck following a relatively brief courtship. Since Dror et al.'s work gave the issue prominence, confirmation bias in forensic evidence has received considerable attention. One key feature of how the authors tackled the Starbuck case was a separation of roles between the two analysts Grant and Grieve (TG and JG). One basic distinction between a stylistic approach and a stylometric approach is that the stylistic approach generally involves a data-driven generation of a case-specific feature set, whereas stylometric analysis tends to rely on predesigned feature sets. A more effective part of the strategy to mitigate bias was the restriction in the flow of text to JG as the analyst. TG wrote a formal expert witness report, explaining the method and crediting JG with his role in the analysis. Risks of unconscious confirmation bias can be mitigated but perhaps never avoided altogether.