One of the first Supreme Court decisions in the ongoing debate about limiting hate speech was in 1978.

It involved the desire of the National Socialist Party, which wore swastikas and promoted white power, to march in the predominantly Jewish Chicago suburb of Skokie. Eventually, the Illinois Supreme Court held that the display of swastikas did not constitute fighting words and thus the enjoining of that speech was an unconstitutional prior restraint. 

The scholarly debate concerning the regulation of hate speech flared again in the late 1980s, primarily focusing on campus speech codes, pitting those who view regulation of hate speech as a necessary step toward social equality against those who see hate speech regulations as abridgements of the fundamental right of free speech.

Read more about hate speech in these encyclopedia articles:

Overview of hate speech and the First Amendment

Campus Speech Codes

Critical Race Theory

Fighting Words

True Threats

Matthew Shepard and James Byrd Jr. Hate Crimes Prevention Act (2009)

Related Court Cases:

Chaplinsky v. New Hampshire (1942)

Village of Skokie v. National Socialist Party of America (Ill) (1978)

Cohen v. California (1971)

R.A.V. v. St. Paul (1992)

Virginia v. Black (2003)