> National Association for the Advancement of Colored People v. Claiborne Hardware Co., 458 U.S. 886 (1982), was a landmark decision of the US Supreme Court ruling 8-0 (Marshall did not participate in the decision) that although states have broad power to regulate economic activities, they cannot prohibit peaceful advocacy of a politically-motivated boycott.

> In a decision by Justice Stevens, the Supreme Court reversed the Supreme Court of Mississippi's decision, holding that the nonviolent elements of the petitioners' activities were protected by the First Amendment to the Constitution of the United States and holding that the petitioners were not liable in damages for the consequences of their nonviolent, protected activity. This decision means that "boycotts and related activities to bring about political, social and economic change are political speech, occupying “the highest rung of the hierarchy of First Amendment values.”

https://en.wikipedia.org/wiki/NAACP_v._Claiborne_Hardware_Co.