These amendments were intended to guarantee freedom to former slaves and to prevent discrimination in civil rights to former slaves and all citizens of the United States. The promise of these amendments was lessened by state laws and federal court decisions over the course of the 19th century. In 1876 and later, some states passed Jim Crow laws that limited the rights of African-Americans. Important Supreme Court decisions that undermined these amendments were the "Slaughter-House Cases" in 1873, which prevented rights guaranteed under the Fourteenth Amendment's privileges or immunities clause from being extended to rights under state law; and "Plessy v. Ferguson" in 1896 which originated the phrase "separate but equal" and gave federal approval to Jim Crow laws. The full benefits of the Thirteenth, Fourteenth, and Fifteenth amendments were not realized until the Supreme Court decision in "Brown v. Board of Education" in 1954 and laws such as the Civil Rights Act of 1964 and the Voting Rights Act of 1965.