It’s easy to have your expert opine exactly what you think you need to support or oppose a summary judgment motion when the expert is not given all of the pertinent facts. In Shiffer v. CBS Corporation, ___ Cal.App.4th ___ (2015 Cal.App. LEXIS 788) [9/8/15], the First District Court of Appeal made clear that “[a]n expert’s opinion is only as good as the facts on which it is built,” and if the expert has not been given the complete set of facts to form an opinion, the expert’s opinion lacks foundation and can be excluded from evidence.

In Shiffer, plaintiff conceded at deposition that the original asbestos-containing insulation on a Westinghouse turbine generator was already installed when he arrived at the job site, and it was never repaired, maintained, installed, or removed in his presence. Westinghouse moved for summary judgment based on no asbestos exposure. In opposition to Westinghouse’s MSJ, plaintiff submitted a contradictory declaration that insulation was being applied on the turbine when he arrived at the job site.

Relying solely on this declaration (and not reading any of plaintiff’s deposition testimony), plaintiff’s experts Charles Ay, Christopher Depasquale, and Barry Horn submitted declarations collectively opining that plaintiff was exposed to Westinghouse’s asbestos which was a substantial factor in causing his mesothelioma. However, the trial court rejected the plaintiff’s declaration because it failed to raise a triable issue of exposure, and the expert declarations because they did not consider plaintiff’s deposition testimony. Finding no admissible evidence of asbestos exposure, summary judgment was granted.

The Court of Appeal affirmed, observing that plaintiff’s experts relied on “a significantly incomplete universe of information, leaving them without an adequate basis” to form their opinions. Under Sargon Enterprises v. University of Southern California (2012) 55 Cal.4th 747, 770, expert opinions “may not be based on assumptions of fact without evidentiary support.” While it remains true that expert declarations in opposition to a summary judgment motion are to be liberally construed, expert opinions may nevertheless lack foundation and be excluded from the summary judgment record if the experts did not analyze the complete set of relevant facts.

An expert never wants to be surprised at a deposition or trial with facts – that if the expert had known about them – would have materially changed the expert’s opinion. The same goes for a pre-trial expert declaration. It is incumbent on counsel to provide their expert with the complete set of relevant facts. This is not just a good tip in managing your relationship with an expert, but it provides a sound foundation to reduce the risk that the expert’s opinion will be excluded from evidence.