Intelligence
What is Confirmation bias?
The tendency to notice and favour evidence that supports what you already believe and to discount evidence against it.
Confirmation bias is the tendency to look for, interpret and remember information in ways that support an existing belief. In intelligence work it shows up when an analyst settles on an early explanation, such as a particular threat actor, and then reads every new clue as support for it.
Structured techniques such as Analysis of Competing Hypotheses, peer review and deliberately searching for disconfirming evidence are the main countermeasures.