If an affidavit is based on an informer's tip, which test must be fulfilled?

When an affidavit is based on an informer's tip, it must meet the totality of the circumstances test. This test requires that a court consider all the surrounding circumstances when evaluating the reliability of the informer's information and the basis for the informant’s knowledge. The totality of the circumstances approach assesses whether the facts presented in the affidavit provide a fair probability that evidence of a crime will be found.

This test is especially important in cases involving informants because individual tips may not be independently sufficient to establish probable cause. By looking at the entirety of the situation—including the informant's credibility, the detail of the information provided, and any corroborating evidence—law enforcement can make a stronger argument for the legitimacy of the search or seizure based on that tip.

Other tests mentioned, such as reasonable suspicion, apply in different contexts, such as during investigatory stops, rather than when determining probable cause from an affidavit. The direct evidence test is not a standard in this context, focusing more on the direct observation of evidence rather than circumstantial accounts. The corroboration test typically involves checking the validity of the informant's claims through additional evidence, but it is not as holistic as the totality of the circumstances test. Therefore, the totality of the circumstances