By David H. Gans, Director of the Human Rights, Civil Rights, and Citizenship Program at the Constitutional Accountability Center. This article was originally written for SCOTUSBlog.

Yesterday’s opinion in McDonald v. City of Chicago is a momentous development in American law.  Concluding that the Fourteenth Amendment requires state and local governments to respect the Second Amendment, Justice Alito’s opinion for the Court roots the Constitution’s protection of substantive fundamental rights in constitutional text and history.  Justice Alito’s opinion covers a wide swath of constitutional text and history – surveying the debates on the Fourteenth Amendment as well as the landmark civil rights legislation enacted contemporaneously with ratification of that Amendment – and more than a century of judicial precedent to demonstrate that the Amendment protects substantive fundamental rights, including the right to bear arms.  Justice Thomas covers much the same ground in his concurring opinion.  The lesson of today’s opinion is that the Fourteenth Amendment’s text and history offer powerful arguments for the protection of fundamental rights.

While the Court declined to restore the vitality of the Privileges or Immunities Clause – the specific text in the Fourteenth Amendment designed to protect substantive fundamental rights from state abridgment – its opinion time and again discusses the text and history of the whole Amendment, including the Privileges or Immunities Clause.  In fact, the Court’s opinion favorably cites a wide scholarship from scholars across the ideological divide arguing that the Privileges or Immunities Clause should be restored.  Rather than revisit the Privileges or Immunities Clause and the Court’s 1873 decision in the Slaughter-House Cases which gutted it, Justice Alito agrees that a robust interpretation should be given to the Due Process Clause.  The weight of Supreme Court precedent, Alito concludes, makes the Due Process Clause a worthy alternative to the Privileges or Immunities Clause that Slaughter-House interred.

Constitutional Accountability Center (CAC) filed a brief in McDonald on behalf of preeminent constitutional scholars in support of restoration of the Privileges or Immunities Clause, which was cited twice in today’s majority opinion.  We argued in our brief and in our report, The Gem of the Constitution, that the Privileges or Immunities Clause should be restored to provide a more secure foundation for the protection of substantive fundamental rights.  While only Justice Thomas voted to breathe new life into the Privileges or Immunities Clause, the recognition, by the Court’s conservative wing, of the critical and historically-supported role of the Fourteenth Amendment in protecting substantive fundamental rights, makes McDonald a path-breaking decision.  After McDonald, claims that the Fourteenth Amendment does not protect the substantive fundamental rights of all Americans should fall on deaf ears.

McDonald, of course, will hardly be the last word from the Court about the Fourteenth Amendment’s protection of substantive liberty.  The Court will still be bitterly divided about what constitutional rights all Americans possess.  But after McDonald, claims that the Court has no constitutional basis to safeguard fundamental rights should lose their force.   As Justice Alito’s opinion convincingly shows, protection of substantive liberties is deeply rooted in the text and history of the Fourteenth Amendment.