08
Tunnel vision & confirmation bias
Once a theory takes hold, contrary facts can disappear from view
Confirmation bias can affect every part of a case when officials favor information that supports an early conclusion and discount evidence that challenges it. The danger grows when one agency repeats another’s assumptions until they appear independently verified.
What failure can look like
- Contrary evidence ignored, minimized, or left out of summaries
- Unverified claims repeated across reports as established fact
- New information interpreted only through the original theory
Protect the record
Create a claim-and-source chart showing who first made each claim, what evidence supports it, what contradicts it, and where it was repeated. Preserve complete records so context is not lost.