What is tunnel vision bias?

• A. Creates an overly broad focus on many possibilities.
• B. Creates an overly narrow focus on a particular investigative theory and leads to unconscious filtering of information.
• C. A bias in clothing choices of investigators.
• D. A phenomenon where jurors ignore forensic evidence.

Answer: (B)

Tunnel vision bias is a cognitive bias that narrows attention to a single theory or hypothesis and causes information that doesn’t fit that idea to be unconsciously filtered out. In a forensic investigation, this means investigators may fixate on one explanation or suspect and, as a result, overlook or misinterpret data that point to other possibilities. The effect is a skewed interpretation of the evidence because the mind is actively filtering what is seen to support the chosen theory rather than evaluating everything objectively. This is why the best description emphasizes both the overly narrow focus and the automatic filtering of information.

Other options miss the mark because they describe something broader or unrelated to investigative thinking: focusing on many possibilities describes the opposite of tunnel vision, the clothing choice bias is not aligned with investigative reasoning, and jurors ignoring forensic evidence reflects a different bias that occurs in the courtroom, not within the investigative process. To minimize tunnel vision bias, use approaches like considering alternative hypotheses, conducting blind or independent reviews, and documenting how conclusions were reached to ensure information isn’t being filtered to fit a narrative.