Katzenbach v. Morgan

The ruling reaffirmed certain powers of Congress by holding it can make laws overriding state laws on the same subject, regardless of the constitutionality of the state law. Congress, in specific, could prohibit enforcement of certain state English literacy voting requirements in New York. The ruling, however, also defined limits to Congress' authority under Section 5 of the Fourteenth Amendment. Congress could only adopt measures for the enforcement of Fourteenth Amendment guarantees.

The notion of universal suffrage (right to vote) in modern times in the United States has dominated public opinion. Recognition of the right to vote and equality at the polls are considered basic for a democracy to properly function. However, voters' rights have not been so widely enjoyed in the past. At the birth of the nation in the late 1700s, only white males with property could vote. The Constitution granted the states the right to establish voting requirements. However, Congress reserved the power to override state laws in Article I of the Constitution.

In 1868, the Fourteenth Amendment was passed extending the previous federal guarantees of due process and equal protection of the law to the states. Section 5 of the amendment reads, "Congress shall have power to enforce, by appropriate legislation, the provisions of this article." Gradually through time voters' rights were expanded, largely through constitutional amendments. The Fifteenth Amendment in 1870 addressed race voting issues, the Nineteenth Amendment in 1920 approved of women's suffrage, the Twenty-third in 1961 extended voting rights to residents of the District of Columbia, and the Twenty-fourth in 1964 eliminated the poll tax requirement.

Into the 1960s, various ethnic minorities continued to encounter barriers in attempting to register to vote. Literacy tests, proving a person could sufficiently communicate in English, frequently served a useful tool by states to restrict voting rights of certain groups of its residents in a discriminatory way. During the 1964 presidential election, African Americans experienced voter registration problems in many regions of the country. Organized voter registration drives often met with bitter, and sometimes violent, opposition. In March of 1965, the Reverend Martin Luther King, Jr. led a protest march from Selma to Montgomery, Alabama, to draw attention to the voting issue. Soon, following the march, President Lyndon B. Johnson presented a sweeping voting rights bill to Congress which quickly passed.