Which of the following cases impacted Fourth Amendment protections at the state level?

Mapp v. Ohio is the case that significantly impacted Fourth Amendment protections at the state level by establishing the exclusionary rule. This legal principle holds that evidence obtained in violation of a person's Fourth Amendment rights, which protect against unreasonable searches and seizures, cannot be used in state courts. Prior to this decision, the exclusionary rule had only applied federally. The Supreme Court's ruling in Mapp v. Ohio extended this protection to state courts, ensuring that states could not use illegally obtained evidence in criminal prosecutions. This case was foundational in reinforcing the right to privacy and due process, allowing citizens to challenge unlawful searches and uphold their constitutional rights against state action.