I took at a look at this article by Neal Devins and David Klein, titled The Power to Bind: Dicta in Theory and Practice some months ago.
The distinction between dicta and holding is at once central to the American legal system and largely irrelevant. In the first systematic empirical study of lower court invocations of the distinction, we show that lower courts hardly ever refuse to follow a statement from a higher court because it is dicta. Specifically, federal court of appeals meaningfully invoke the distinction in about 1 in 5, 000 cases; federal district courts in about 1 in 3,000 cases; and state courts in about 1 in 3,000 cases. In this essay, we report these findings, describe our coding system, and offer a preliminary assessment of the implications of our study. Most notably, our findings cast doubt on the vitality of traditional common law judging. Rather than play a significant role in the development of legal principle by treating extraneous statements in higher court rulings as non-binding dicta, lower courts cede much of their common law power to higher courts. Higher courts can issue sweeping rulings that address questions not immediately before them, knowing that those statements will not be treated as dicta. In highlighting this dynamic between lower and higher courts, our study also casts light on the ongoing debate over judicial minimalism. The ability of courts to pursue the minimalist project of issuing narrow fact-specific rulings is undercut by a regime in which lower courts look to higher courts for the enunciation of legal principles. Finally, our study is highly salient to the practice of law. Lawyers, while frequently referencing the holding-dicta distinction in legal briefs, have little reason to think that a lower court will ever invoke the distinction to rule against higher court dicta.
I wrote about the distinction between dicta and holding years ago. I hope to revisit it at some point.