That evidently happened in Secrest, and produced contradictory treater testimony so grotesque that the Second Circuit recoiled, calling it a "sham" in a for-publication decision.
Here's an outline. Plaintiff took Fosamax over a period of years prescribed by Dr. X and then Dr. Y. Dr. Y apparently did not testify, or at least his testimony was considered irrelevant by both sides. Dr. X testified as a fact witness that at the time plaintiff suffered her injury (bone deterioration in the jaw - "ONJ") he (Dr. X) "was not aware" that plaintiff continued to take Fosamax (then being prescribed by Dr. Y). Secrest, slip op. at 5.
Then the defendant moved for summary judgment against the warning claim on causation grounds - because if Dr. X didn't know about plaintiff's Fosamax use, he couldn't have been affected by an allegedly inadequate warning. Why would a treater say anything about the risks of a drug that s/he didn't know that the plaintiff was taking?
After the motion was filed, up popped Dr. X again - this time serving as the plaintiff's expert.
To any naif out there, that means Dr. X was now on the plaintiff's payroll.
Predictably, Dr. X has changed his tune, offering utterly contradictory testimony in a second expert deposition that he actually did know about plaintiff's Fosamax use during the critical time. Specifically:
By contrast, in his [second] deposition, Dr. [X] testified that he “knew she was on [Fosamax]” in [the critical time] and that, had [defendant] warned him about the risk of ONJ, he would have recommended that [plaintiff] stop taking Fosamax.Secrest, slip op. at 5. As the court pointed out "[o]nly after he was designated as plaintiff's expert" did Dr. X experience an epiphany of recollection that led to this contradictory testimony.
Neither the district court (which granted summary judgment anyway) nor the Second Circuit was having any part of Dr. X's changed testimony.
It was a "sham."
[C]onsidering Dr. [X]’s clearly contradictory testimony . . . we hold that the District Court was entitled to disregard Dr. [X]’s new testimony relating to his knowledge based on the “sham issue of fact” doctrine, which prohibits a party from defeating summary judgment simply by submitting an affidavit that contradicts the party’s previous sworn testimony. Although we have typically applied the sham issue of fact doctrine where a party submits an affidavit that contradicts the party’s own prior statements, it may also apply when a party attempts to use evidence from an expert witness to defeat summary judgment.Secrest, slip op. at 7. The subsequently procured "expert" testimony could be disregarded "where the relevant contradictions between the first and second depositions are unequivocal and inescapable, unexplained, arose after the motion for summary judgment was filed, and are central to the claim at issue." Id. at 8.
Moreover, the plaintiff "ha[d] not proffered a plausible explanation" for Dr. X's testimonial gymnastics, but only argued that "credibility determinations are left to the jury." Id. at 9. The timing - after the filing of a summary judgment motion - was also extremely suspect. Id. at 10. Thus summary judgment was affirmed.
That's as close as you'll see an appellate court come to calling a witness a liar without actually doing so.
Schadenfreude - it feels good.
For the record, after summary judgment was granted on the warning claims in Secrest, non-warning claims (design defect) were tried to a jury and plaintiff lost again. The Second Circuit also summarily affirmed the jury verdict in a second, unpublished opinion, here.