The Civil Rights Act of 1964 prohibits discrimination of race, color, religion, sex, or national origin. Passage of this act ended the application of "Jim Crow" laws, which was upheld by the supreme court in the 1896 case Plessy v. Ferguson, in which the court held racial segregation that was meant to be "separate but equal" and was considered constitutional. The Civil Rights Act was eventually expanded by congress to strengthen the enforcement of these fundamental Civil Rights. This act was a landmark piece of legislation in the U.S. that outlawed discrimination in any form. It ended unequal voter registration requirements and segregation in schools, at workplace, and by facilities that served the general public. Congress used this acts principle power to regulate interstate commerce under Article One, its duty is to guarantee all citizens equal protection under the 14th Amendment. Voting rights were placed under the 15th Amendment.