Exclusionary rule does not apply to which proceedings?

• A. Grand jury proceedings
• B. Criminal trials
• C. Civil trials
• D. All of the above

Answer: (A)

The key idea is that the exclusionary rule is a remedy aimed at criminal prosecutions, preventing evidence gathered in violation of the Fourth Amendment from being used at trial to obtain a conviction. Grand jury proceedings are not trials; they decide whether there is probable cause to indict, and the exclusionary rule does not apply in that setting. This was established in Costello v. United States, which holds that illegally obtained evidence can be considered by a grand jury. Therefore, the exclusionary rule does not apply to grand jury proceedings. In contrast, when a criminal trial occurs, the rule does apply to bar such evidence; civil proceedings fall outside this criminal-prosecution remedy.