Confirmation bias is often described as an interviewer problem.In reality, it frequently begins long before the interview itself.Investigators are trained to recognize patterns, interpret behaviors, and make rapid assessments under pressure. The danger emerges when those assessments become presumptive—when early interpretations begin shaping how information is heard, filtered, and pursued.Once an interview becomes presumptive, the interviewer may unknowingly begin:
• seeking confirmation instead of clarification,
• interpreting uncertainty as deception,
• overlooking contradictory information,
• and feeding details that contaminate reliability.The result is not simply a poor interview.It is an interview shaped by premature cognitive commitment.