This chapter begins with an empirical analysis of attitudes towards the law, which, in turn, inspires a philosophical re-examination of the moral status of the rule of law. In Section 2, we empirically analyse relevant survey data from the US. Although the survey, and the completion of our study, preceded the recent anti-police brutality protests sparked by the killing of George Floyd, the relevance of our observations extends to this recent development and its likely reverberations. Consistently with prior studies, we find that people’s ascriptions of legitimacy to the legal system are predicted strongly by their perceptions of the procedural justice and lawfulness of police and court officials’ action. Two factors emerge as significant predictors of people’s compliance with the law: (i) their belief that they have a (content-independent, moral) duty to obey the law (which is one element of legitimacy, as defined here); and (ii) their moral assessment of the content of specific legal requirements (‘perceived moral content of laws’). We also observe an interactive relationship between these two factors. At higher levels of perceived moral content of laws, felt duty to obey is a better predictor of compliance. And, similarly, perceived moral content of laws is a better predictor of compliance at higher levels of felt duty to obey. This suggests that the moral content incorporated in specific laws interacts with the normative force people ascribe to legal authorities by virtue of other qualities, specifically here procedural justice and lawfulness. In Section 3, the focus shifts to a philosophical analysis, whereby we identify a parallel (similarly interactive) modality in the way that form and content mutually affect the value of the rule of law. We advocate a distinctive alternative to two rival approaches in jurisprudential discourse, the first of which claims that Lon Fuller’s eight precepts of legality embody moral qualities not contingent on the law’s content, while the second denies any independent moral value in these eight precepts, viewing them as entirely subservient to the law’s substantive goals. In contrast, on the view put forward here, Fuller’s principles possess (inter alia) an expressive moral quality, but their expressive effect does not materialise in isolation from other, contextual factors. In particular, the extent to which it materialises is partly sensitive to the moral quality of the law’s content.