Coppage v. Kansas

With the growth of labor unions in the nineteenth century and the early twentieth century, employers looked for ways to hire lower-wage workers. One of the more successful methods employers used was having potential employees sign contracts declaring that they were not presently union members and that they would not become union members, or what became known as yellow-dog contracts.

Although some states had laws that prohibited employers from forcing employees to sign yellow dog contracts, in 1915 the U.S. Supreme Court struck down such state laws as unconstitutional, arguing that they obstructed the freedom of contract of both employers and employees. However, Congress passed the Norris-LaGuardia Act of 1932 that prohibited yellow-dog contracts. The Norris-LaGuardia Act strengthened the position of labor unions and its policies became the standard means for resolving labor disputes in following years.