Judge Burke last month addressed a motion to strike portions of an expert report regarding commercial acceptability of a non-infringing alternative.
As set forth in the report, an expert may rely on experience in the industry, but must explain "how that experience leads to the conclusions reached." Here, the expert opined that an alternative was commercially acceptable, but did not set forth why.
Then, when asked for more detail at his deposition, he responded with a snide comment:
[D]uring his deposition, [the expert] very ill−advisedly made things worse when he responded to a question on this subject by flippantly suggesting that he had "no backing" for the conclusion, and had simply "put [it] in on purpose" because Plaintiffs' expert similarly had "no backing" for many of his opinions in the case.
In other words, when asked where the support was for his opinion, he joked that there was none and that he was just trolling the other sides expert, since that expert's views were so unsupported.
That's obviously not a great thing to have on the record.
Judge Burke ultimately let him off the hook, though, as the expert actually had explained a sufficient basis for his conclusions in a prior paragraph of his report:
But with all that being said, Mr. Waadevig and Defendant subsequently made clear that this deposition comment was meant in jest. . . . More importantly, in paragraph 38 of his responsive expert report, Mr. Waadevig had explained [the bases for his opinion].
All told, it worked out okay for defendants, but I bet they'll be prepping that expert better next time.