Katzenbach v. Morgan, 384 U.S. 641 (1966), was a landmark decision of the Supreme Court of the United States regarding the power of Congress, pursuant to Section 5 of the 14th Amendment, to enact laws that enforce and interpret provisions of the Constitution. Background Prior to the 1960s, many US states and municipalities used literacy tests to disenfranchise minorities. In 1959, the Supreme Court of the United States held, in Lassiter v. Northampton County Board of Elections, that literacy tests were not necessarily violations of the Equal Protection Clause of the 14th Amendment, nor of the 15th Amendment. In 1965, Congress passed the Voting Rights Act of 1965, which sought to safeguard the voting rights of disenfranchised minorities. Among other provisions, the Voting Rights Act made some literacy tests illegal. Section 4(e) was aimed at securing the franchisement of New York City's large Puerto Rican population and "provides that no person who has completed the sixth grade in a public school, or an accredited private school, in Puerto Rico in which the language of instruction was other than English shall be disfranchised for inability to read or write English." Registered voters in the state of New York brought suit by alleging that Congress exceeded its powers of enforcement under the 14th Amendment and alleging that Congress infringed on rights reserved to states by the 10th Amendment. Decision By a 7–2 decision, the Supreme Court sided with Attorney General Nicholas Katzenbach, reversed the District Court, and held that Section 4(e) was constitutional. Writing the majority opinion, Justice Brennan stressed that Section 5 of the amendment is "a positive grant of legislative power authorizing Congress to exercise its discretion in determining the need for and nature of legislation to secure Fourteenth Amendment guarantees." Justice Brennan applied the appropriateness standard of McCulloch v. Maryland (1819) to determine whether the legislation passed constitutional muster. Section 4(e) arguably expanded rights beyond what the Court had recognized in Lassiter, but Brennan ruled that Section 4(e) was appropriate. In doing so, he has often been credited with introducing the "ratchet theory" for congressional legislation enacted under Section 5. It held that Congress could ratchet up civil rights beyond what the Court had recognized, but Congress could not ratchet down judicially recognized rights. The "ratchet theory" essentially set judicially recognized rights as a support on which Congress could expand if it so chose. According to the theory, Brennan's