ASIS Professional Certified Investigator Practice Exam 2026 – Complete Study Guide

The exclusionary rule, as established in US v. Janis, primarily pertains to criminal cases. This rule is a judicially created principle that prevents evidence obtained through violations of a defendant's constitutional rights from being used in court. In the context of US v. Janis, the Supreme Court reinforced the idea that the exclusionary rule applies specifically to criminal prosecutions, emphasizing its role in deterring unlawful police conduct and protecting the rights of defendants under the Fourth Amendment.

While the exclusionary rule's application to civil cases has been considered, it was not established as part of this particular ruling. Therefore, the focus remains on its application to criminal law, where the rule serves as a crucial mechanism for upholding justice and ensuring due process.