Brandenburg Test

The Brandenburg Test is a legal framework used to determine whether or not free speech can be limited in cases where it stands to incite violence or crime. It replaced the "clear and present danger" test established by the 1919 Supreme Court case Schenck v. United States.

According to the Brandenburg Test, the government may legally prohibit speech if:


 * 1) Speech is "directed to inciting or producing imminent lawless action" and
 * 2) Speech is "likely to incite or produce such action"

Brandenburg v. Ohio
The Brandenburg Test was established in 395 U.S. 444 (1969), Brandenburg v. Ohio.

In this case, Clarence Brandenburg, a rural Ohio KKK leader was appealing a $1000 fine and prison sentence. He was charged with: advocat[ing]… the duty, necessity, or propriety of crime, sabotage, violence, or unlawful methods of terrorism as a means of accomplishing industrial or political reform

and for

voluntarily assembl[ing] with any society, group or assemblage of persons formed to teach or advocate the doctrines of criminal syndicalism.

All this is to say that the guy advocated for "revengeance" against the usual cast of characters targeted by racists. According to the state of Ohio, advocating for revenge against these groups of people constituted a criminal act. The United States Government thought otherwise, since it didn’t advocate for imminent action.

Aftermath
Since Brandenburg v. Ohio (1969), the Brandenburg Test has been accepted by proponents of free speech as protecting America’s First Amendment right. It is often cited as an "unfortunate price of freedom".