One does not progress far into legal life without learning that there is no single right and accurate way of reading one case, or of reading a bunch of cases. For
(1) Impeccable and correct doctrine makes clear that a case "holds"with authority only so much of what the opinion says as is absolutely necessary to sustain the judgment. Anything else is unnecessary and "distinguishable" and noncontrolling for the future. Indeed, if the judgment rests on two, three or four rulings, any of them can be rightly and righteously knocked out, for the future, as being thus "unnecessary." Moreover, any distinction on the facts is rightly and righteously a reason for distinguishing and therefore disregarding the prior alleged holding. But
(2) Doctrine equally impeccable and correct makes clear that a case "holds" with authority the rule on which the court there chose to rest the judgment; more, that that rule covers, with full authority, cases which are plainly distinguishable on their facts and their issue, whenever the reason for the rule extends to cover them. Indeed, it is unnecessary for a rule or principle to have led to the decision in the prior case, or even to have been phrased therein, in order to be seen as controlling in the new case: (a) "We there said.. ." (b) "That case necessarily decided ..." These divergent and indeed conflicting correct ways of handling or reading a single prior case as one "determines" what it authoritatively holds, have their counterparts in regard to the authority of a series or body of cases.
Karl N. Llwellyn,
Remarks on the Theory of Appellate Decision and the Rules or Canons about how Statutes are to be Construed,
3 Vanderbilt Law Review
Available at: https://scholarship.law.vanderbilt.edu/vlr/vol3/iss3/24