In Abernathy et al. v. Alabama (1964), the U.S Supreme Court overturned the convictions of five civil rights activists, including Ralph David Abernathy, a close associate of Martin Luther King Jr., who were found guilty by an Alabama court for their participation in a 1961 "Freedom Ride" protest against racial segregation on interstate buses and bus terminals. The defendants had been convicted under an Alabama statute that made it illegal to conspire without lawful authority to obstruct or hinder free passage through any public highway or street. In its decision, the Supreme Court held that peaceful protests and demonstrations could not be considered as obstruction of free passage under this law because they did not involve violence or threats of violence nor did they physically block access to streets or highways.

In the dissenting opinion for Abernathy et al. v. Alabama, Justice Harlan argued that the majority's decision to overturn convictions of civil rights protesters on grounds of free speech was incorrect and overly broad in its interpretation of First Amendment protections. He contended that while peaceful protest is protected under the Constitution, it does not extend to actions which disrupt public order or infringe upon others' rights - such as blocking traffic or creating a public nuisance - both activities these protestors were accused of doing during their demonstration against racial segregation laws in Birmingham, Alabama. Furthermore, he disagreed with the majority's view that state courts should be held to federal standards when interpreting local ordinances related to protests and demonstrations; instead believing each state has a right to enforce its own laws within reason without interference from federal authorities unless there is clear evidence they are being used unjustly or discriminatorily.