Harm and the First Amendment: Evolving standards for 'proving' speech-based injuries in U.S. Supreme Court opinions

This study reviews the United States Supreme Court's proof-of-harm doctrine in freedom of expression analysis. It analyzes thirty-eight Supreme Court cases beginning in 1919 and ending with discussion of its most recent free speech opinion in 2013.;Free speech jurisprudence has never adhered to a position of absolute protection for expression, a position that would render all laws restricting expression unconstitutional. Rather, the Court has more often engaged in a balancing approach that weighs the government's interest in regulating potentially harmful speech against the value of the expression. Examination of more recent Supreme Court constitutional jurisprudence reveals a trend away from its historical balancing that deferred to legislative and congressional fact-finding to one that requires sufficient scientific evidence.;Alternatively, the Court's free speech jurisprudence demonstrates it has not adopted an empirical approach across all brands of expression. In this sense, United States v. Alvarez and Brown v. Entertainment Merchants Association, two prominent opinions adopting stringent evidentiary burdens requiring empirical proof of harm, may more accurately represent outliers to its usual approach adopting much lower evidentiary burdens. Until the Court has additional time to consider application of its empirical approach to a broader spectrum of expression, it is perhaps unclear whether Brown and Alvarez represent a "mini-trend" within the Court's jurisprudence or are part of a lengthier trajectory.;This study proposes a typology of factors it found to have potentially affected the Court's assessment of its requirement of proof-of-harm, including the specific evidentiary burden imposed. In this sense, "evidentiary" refers to the type and amount of evidence it required or evaluated to make its determination regarding the constitutionality of the allegedly harmful expression. It also proposes a rubric for helping courts assess the burden of proof-of-harm it should adopt when evaluating specific speech-based claims. The requirements of assessment of an evidentiary burden of proof of harm in specific factual scenarios set forth in the rubric in based on the Court's own assessment of the nature of harm, types of speech and evidence, including the type and quantity, required or evaluated in its First Amendment opinion. The purpose of these tools---the typology and rubric---is to assist the development of a better understanding of the relationship between speech and harm in First Amendment jurisprudence.