Anti-discrimination law
The Civil Rights Act of 1964 was the first major development in anti-discrimination law in the US, though prior civil rights legislation (such as the Civil Rights Act of 1957) addressed some forms of discrimination, the Civil Rights Act of 1964 was much broader, providing protections for race, color, religion, sex, or national origin in the areas of voting, education, employment, and public accommodations. This landmark legislation led the way for other federal legislation, which expanded upon the protected classes and forms of discrimination prohibited under federal legislation, such as the Fair Housing Act or the Americans with Disabilities Act. These protections have also been expanded through the courts interpretation of these pieces of legislation. For example, the 7th and 2nd circuit courts have both ruled that employment discrimination based on sexual orientation is a violation of Title VII of the Civil Rights Act. In addition to federal legislation, there are numerous state and local laws that address discrimination that is not covered by these laws.
Communications Workers of America v. Beck
In the United States, unions established the closed shop, union shop, and agency shop since at least the 1880s. The National Labor Relations Act (NLRA), the primary federal law governing labor relations in the United States, was enacted in 1935 and formally legalized the closed shop, union shop, or agency shop. In 1947, however, Congress enacted the Taft-Hartley Act, which amended the NLRA. Title I, Section 101 of the Taft-Hartley Act added a new Section 14 to the NLRA, part (b) of which banned the closed shop:
Nothing in this Act shall be construed as authorizing the execution or application of agreements requiring membership in a labor organization as a condition of employment in any State or Territory in which such execution or application is prohibited by State or Territorial law.
The Taft-Haftley Act did not, however, outlaw the union shop or agency shop (although it did place some procedural restrictions on their establishment and use).