It is entirely unclear as to whether the opinion given from the bench (which was the one which was voted upon as the decision) is the one Taney eventually published. In fact, it is quite clear that Taney violated the rules of the Supreme Court by not immediately turning the opinion over to the Clerk for publication ("The Supreme Court Rule 25 (in force since 1834) declared: 'All opinions delivered by the court shall, immediately upon delivery thereof, be delivered over to the clerk to be recorded.'"). Instead, Taney took back the decision and added, what was estimated to be at the time, about 50% more text.
In other words, the dishonest Chief Justice may very well have published an opinion that was not, on key points of law and documentation, the one that had been voted upon by the other Justices.
Justice Curtis correctly surmised that Taney was re-writing the decision to address the dissents. "What had been added, Taney continued in an incredible passage, were certain proofs and authorities to support historical facts and legal principles asserted in his oral opinion but denied in the dissenting opinion. 'And until the Court heard them denied, it had not thought it necessary to refer to proofs and authorities to support them - regarding the historical facts and the principles of law which were stated in the opinion as too well established to be open to dispute.' Here, covered over with a good deal of self-righteous indignation, was the plain acknowledgment that Taney revisions were indeed rebuttal to certain parts of the dissenting opinions." (Fehrenbacher, pg 318).
Fehrenbacher concludes that particular chapter, with the observation:
"It therefore appears that Curtis was substantially correct in his critique of the published opinion. Taney's denial of having made any significant changes, though perhaps not untruthful according to his own peculiar lights, must be labeled inaccurate. The so-called opinion of the Court included a considerable of material that few, if any, of the justices heard or read before its publication. And much of this new material was rebuttal to the dissenting opinions of Curtis and McLean. Another complication is thereby added to an already labyrinthine case, and especially to the question that has fascinated and confused several generations of historians and legal scholars: What did the Court actually decide?"
Bwahahahaha! It's not the justices opinion until they are thru with it, and the final copy is published. Justices routinely revise and direct comments regarding differing opinions on a case. That is how their opinion can cite from the other opinions for the same case.
Currently an opinion may be revised and presented at least three times before the "final" printing. A "bench opinion", a "slip opinion", "preliminary prints", and the final US Reports version.