Which case was involved in applying federal constitutional protections to the states through the Fourteenth Amendment?

• A. Mapp v. Ohio
• B. Miranda v. Arizona
• C. Gideon v. Wainwright
• D. Gitlow v. New York

Answer: (D)

Incorporation through the Fourteenth Amendment binds state governments to federal rights. Gitlow v. New York (1925) is the milestone here: the Court held that the First Amendment’s freedoms of speech and press are applicable to the states through the Fourteenth Amendment’s Due Process Clause. This began the incorporation doctrine, establishing that federal constitutional protections do not only restrain the federal government but also constrain state governments. Later cases expanded this approach to other rights. The other listed cases involve different amendments or later incorporations (for example, Mapp v. Ohio extends the Fourth Amendment’s exclusionary rule to the states, Gideon v. Wainwright guarantees counsel in state courts, and Miranda v. Arizona reinforces interrogation rights), but the question points to the case that first explicitly applied federal protections to the states via the Fourteenth Amendment, which is Gitlow v. New York.