The Epistemology of Expertise

Strobel v. Johnson & Johnson, No. A159609 (D1d4 Oct. 21, 2021).

Since I became a lawyer, there have been two things I have always gone out of my way to avoid having any understanding of—ERISA and asbestos. This case deals with the latter. But it’s got an interesting evidentiary issue. So I’ll muddle through despite all the death and mineralogy. Just don’t tell anyone.

The main issue is about experts and hearsay. If you think about it, what we consider to be expertise is often largely a compilation of hearsay. We read lots and lots of books and sooner or later we know some stuff. I know what happened in Brown v. Board of Education because I read the opinion and commentary about it, not because I was in the courtroom observing with firsthand personal knowledge. And I know what’s in Code of Civil Procedure because I read my gold book and Witkin, not because I sat with the Assembly and watched the Governor sign the bills. And so it is with the kinds of folks who offer opinion testimony about whether some product had asbestos in it in 1964. 

If experts can’t testify to some hearsay, they could often offer little more than their unadorned opinions, which would not be very useful to the trier of fact. On the other hand, an expert shouldn’t be used as a vehicle to smuggle otherwise inadmissible hearsay into the jury box. The California Supreme Court addressed this issue in a criminal case called People v. Sanchez, 63 Cal. 4th 665, 670 (2016). 

In Sanchez, the Court explained that under Evidence Code §§ 801(b) and 802, an expert could provide “testimony concerning background information regarding his knowledge and expertise and premises generally accepted in his field” without running afoul of the hearsay rule. But “[i]f an expert testifies to case-specific out-of-court statements to explain the bases for his opinion, those statements are necessarily considered by the jury for their truth, thus rendering them hearsay.” 

So in Sanchez, the expert’s testimony that he relied on someone else’s having designated the defendant as a gang member was inadmissible hearsay that should not have been admitted into evidence. Later cases illustrate that the distinction lies around whether the alleged hearsay is the kind of non-case-specific background material that an expert in the field would ordinarily rely on. Compare People v. Veamatahau, 9 Cal. 5th 16, 26 (2020) (reliance on database to identify pill based on marking admissible) with People v. Valencia, 11 Cal. 5th 818 (2021) (expert’s testimony that defendant had committed prior offenses qualifying for enhancement was inadmissible hearsay).

Here, in support of his opinion that some mid-century baby powder contained asbestos, the plaintiff’s expert offered declaration testimony about testing of historical samples of the same powder at issue conducted by some other expert who did not testify in the case. The court here says that runs afoul of Sanchez. You can’t use an expert’s ability to testify on what he or she relied on to sneak in opinion testimony from some other undesignated expert who is not subject to cross.

The Court holds, however, that even without the hearsay, the expert relied on enough reasonable material to apply his expertise to submit an opinion that, if believed, could support a finding that there was asbestos in the power. So his declaration was adequate to defeat summary judgment.

Reversed.