Which cases establish that the exclusionary rule applies to both federal and state courts?

• A. Weeks v. United States; Mapp v. Ohio.
• B. Miranda v. Arizona.
• C. Gideon v. Wainwright.
• D. Brown v. Board of Education.

Answer: (A)

The key idea is how the exclusionary rule reaches both federal and state courts. Weeks v. United States established the exclusionary rule for federal prosecutions, preventing illegally obtained evidence from being used in federal courts. To ensure the same protection at the state level, Mapp v. Ohio applied the Fourteenth Amendment’s due process clause to incorporate the rule, making it binding on state courts as well. Together, these cases show the rule’s reach across the entire judiciary, federal and state. The other listed cases deal with different constitutional rights—Miranda with warnings during custodial interrogation, Gideon with the right to counsel, and Brown with desegregation—so they don’t illustrate the nationwide application of the exclusionary rule in the same way.