Identify the 1973 court case that clearly established artists' freedom of expression.

The court case in 1973 that established artists freedom of expression was Miller v. California. In the Miller v. California case, a landmark decision was made by the supreme court which decided to change the definition of obscenity, it once meant something that had absolutely no social value, now it is something that lacks serious artistic, political, literary or scientific value. This has formed the three prong test, referred to as the MIller test.