This chapter provides an overview of defamation law, discussing key civil rights-related cases with a focus on the landmark New York Times v. Sullivan case from 1964, which rewrote American libel law. Sullivan finds new relevance for today’s students of media law given that the case arose out of accusations of police brutality of civil rights demonstrators. In the wake of the Black Lives Matter movement and discourse surrounding police brutalization of protesters, we must not take for granted our right to criticize our elected officials and government actors, notably an increasingly militarized police. Journalists today also face increased attacks via libel law by public officials, partisans who are using libel as a cudgel to silence coverage of them that they do not like. The chapter also surveys the evolution of libel laws in Sullivan’s progeny and outlines defenses for media defendants in defamation cases, drawing striking comparisons between the civil rights revolution of the 1960s and today.