Which practice best reduces bias when evaluating informant reliability?

• A. Rely solely on their stated motives.
• B. Ignore corroborating evidence.
• C. Focus on their appearance or popularity.
• D. Check corroborating evidence, analyze consistency over time, and assess reliability and motives.

Answer: (D)

Evaluating informant reliability without bias comes from verifying what you’re told with solid evidence and looking at how trustworthy the source has been over time. The best approach is to check corroborating evidence, analyze consistency across multiple reports or time periods, and assess both the informant’s reliability and their possible motives.

Corroborating evidence means confirming statements with independent sources or records rather than taking them at face value. This helps guard against personal bias or manipulation. Looking for consistency over time shows whether the informant’s statements remain stable and accurate, rather than being influenced by a single moment or situation. Assessing reliability and motives helps you consider why the informant might distort information—whether for gain, fear, retaliation, or other incentives—so you weigh their reports with that context in mind.

Relying only on motives, ignoring corroboration, or judging by appearance or popularity introduces bias and can lead to faulty conclusions. When you combine multiple checks—independent corroboration, cross-time consistency, and motive/reliability assessment—you reduce the chance of bias coloring your evaluation of the informant.