Linear Sequential Unmasking (LSU)
Definition
A protocol in which an analyst processes evidence in a fixed order and receives case context only at the stage where it becomes scientifically necessary, with each stage documented before the next is revealed, to prevent contextual information from contaminating the primary analysis.
- Purpose
- Prevent contextual bias from contaminating analysis
- Method
- Fixed processing order, staged release of context
- Requirement
- Each stage documented before the next is revealed
Common questions
How does LSU differ from simply withholding all case information?+
Full blinding is often impractical since some context is scientifically necessary. LSU releases that context only at the stage where it is needed, after the bias-prone primary observations are already locked in.
Why does the documented order of stages matter under LSU?+
The analyst's findings and reasoning at each stage are recorded before moving on, so a later stage's context cannot retroactively reshape an earlier conclusion, and reviewers can trace exactly when information was introduced.
Related terms
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- Contextual Bias
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- Foundational Validity
- The requirement, articulated in the 2009 US National Academy of Sciences report and taken up by courts and reform bodies, that a...
- PCAST
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