We theorize that if law matters in Supreme Court decision making, it matters not as a mechanistic force that dictates decisions, but as an institutional construct created by justices who possess political attitudes. Jurisprudential regimes identify relevant case factors and/or set the level of scrutiny or balancing the justices will use. These jurisprudential regimes have the potential to make a significant difference in the decisions of the justices. We identify a candidate jurisprudential regime, content-neutrality, which appears to govern the general area of free expression law. The Court applies the strictest standard of review to regulations of expression that target the content or viewpoint of expression. Relying on a series of statistical tests using logistic regression, we find that the justices take seriously this jurisprudential regime.