what are the four main eras in U.S. constitutional law interpretation?

Answer 1

I have never heard it described in that way so I will give you my take on the eras.

1) The Marshall Court (1800-1835) -- This Court was characterized by a moderately broad reading of the powers of the federal government and of the Court. Most famous for Marbury vs. Madison, McCulloch v. Maryland, and Barron v. City of Baltimore.

2) The Taney Court (1835-1865) -- This Court strictly construed enumerated powers. Most famous for the Dredd Scott case.

3) The Reconstruction Era (1865-1895) -- This era saw the Supreme Court strictly construed the newly enacted Civil War Amendments as granting few new powers to the Court or to Congress or placing many restrictions on the states. Most famous for the Slaughter House Cases, the Civil Rights Cases, Plessy v. Ferguson, Hurtado v. California.

4) The Lochner Era (1895-1937) -- This era saw the Supreme Court narrowly interpreting Congressional Powers while broadly interpreting the Fourteenth Amendment's due process clause to strike down many state laws regulating economic activities including minimum wage and maximum hours laws. As the name of the era notes, the most famous decision of this era was Lochner v. New York. There was some increased enforcement of the Bill of Rights against the states.

5) The New Deal Court (1937-1947) -- This era saw the repudiation of Lochner in a series of decisions. Part of this repudiation saw the rise of the current very broad view of national powers to enact legislation. While the Court noted the possibility of continued activism to enforce the Bill of Rights and the equal protections clause (most famously in the Carolene Products decision), there were only a handful of such cases in this era, mostly the Jehavah Witnesses Flag cases.

5) The Warren Court era (1947-1973) -- While this era is typically named after Chief Justice Earl Warren, the era actually began before his appointment and continued after his retirement. This case saw great activity in broadly interpreting the Constitution to prevent racial discrimination and to enforce the principles of the Bill of Rights. Cases from this era include Brown v. Board of Education, Gideon v. Wainwright, Miranda, Roe v. Wade, the new Civil Rights Cases, Lemon, the Pentagon Papers, etc.

6) Post-Warren Court (1973-present) -- The general trend since 1973 has been to nibble at the decisions of the Warren Court era. There have been no major decisions overturned (except Furman). Instead, the general tendency as been decisions to narrow the reach of the broad decisions of the Warren Court era.