What is the Aguillar Test?

• A. Informants Must Be Credible and Have a Basis for Information
• B. Informants Must Be Residents of the Area
• C. Informants Must Disclose Sources
• D. Informants Must Pass a Lie Detector Test

Answer: (A)

Informants must be credible and have a basis for their information. This principle, historically known as the Aguilar test, is about making sure tips used to justify a warrant come from a trustworthy source and are grounded in reality. Credibility looks at whether the informant is likely to tell the truth based on past reliability, while basis of knowledge requires that the information either come from the informant’s own observations or from information they can directly support with specifics. The goal is to ensure the information offered can be verified and is not just rumor. If either element isn’t present, the tip may not be enough to establish probable cause. The other options—residency in the area, disclosure of sources, or passing a lie detector test—are not part of this standard.