There remains either disagreement or misunderstanding as to when an expert may [or must] repeat hearsay relied on to reach an opinion. At a Masters in Trial Advocacy EVIDENCE lecture we presented the following hypothetical:

 An expert comes to court to testify about how a construction accident occurred. The expert states “I went to the scene, I reviewed the photos and news video, I conducted my own tests, and then I interviewed four bystanders.”
 May the expert now repeat what the bystanders said?

In federal court the expert would not be allowed to repeat the bystander comments as (1) they met no hearsay exception and (2) Federal Rule of Evidence 703 precludes such proof unless its probative value [the need to explain how they expert reached a conclusion] outweighs the unfair prejudice [bringing in assertions that can’t be challenged].

For Pennsylvania we asserted that the hearsay had to be repeated, because Pa.R.Evid. 703 does not include the limiting language in the federal version and because Pa.R.Evid. 705 requires an expert to disclose all facts the expert considered. “If an expert states an opinion the expert must state the facts or data on which the opinion is based.”

We had dissents regarding the Pennsylvania analysis, with one lawyer expressing the belief that this was never allowed and a judge expressing Rulke 403 concerns. This research followed, confirming that Pennsyhlvania mandates disclosure. Here is a lengthy excerpt from a 2018 case discussing this:

The Pennsylvania Superior Court has stated:

It is well-established that an expert may express an opinion which is based on material not in evidence, including other expert opinion [sic], where such material is of a type customarily relied on by experts in his or her profession. Collins v. Cooper, 2000 PA Super 22, 746 A.2d 615, 618 (Pa. Super. 2000); Primavera v. Celotex Corp., . . . 415 Pa. Super. 41, 608 A.2d 515 ([Pa. Super.] 1992). Such material may be disclosed at trial even though it might otherwise be hearsay . . . . Such hearsay is admissible because the expert’s reliance on the material provides its own indication of the material’s trustworthiness: ‘The fact that experts reasonably and regularly rely on this type of information merely to practice their profession lends strong indicia of reliability to source material, when it is presented through a qualified expert’s eyes.’ Primavera, 608 A.2d at 520.

Boucher v. Pa. Hosp., 2003 PA Super 282, 831 A.2d 623, 628 (Pa. Super. 2003) (emphasis added)…

In Primavera, our Superior Court explained:

In noting the necessity and value of permitting experts to rely on extrajudicial reports and sources, it is important to stress that it is actually the testifying expert’s opinion which is being presented and which is subject to scrutiny, cross-examination and credibility determinations. Hence, it is often the case, as it was here, that experts are questioned concerning whether relied-upon sources are ‘authoritative’ or generally accepted, whether the source material is truly the type ordinarily relied on by similar experts, whether independent or further judgment was brought to bear on particular source material and whether the expert is competent enough to judge the reliability of the sources upon which he relied. These are the safeguards which assure that the experts’ opinions are not being offered based on inherently untrustworthy data or data which is not commonly used by other professionals. If an expert has made faulty assumptions or leaps of judgment in relying on certain sources or in forming conclusions based on those sources, these issues are the proper subject of cross-examination.

As this court has indicated, the crucial point is that the fact-finder be made aware of the bases for the expert’s ultimate conclusions, including his partial reliance on indirect sources. ‘The adverse party then has the opportunity . . . to present its own countervailing facts and figures and/or expert testimony to convince the factfinder that the weight to be given to the other side’s expert testimony should be little or none’. In re Glosser Bros., Inc., 382 Pa. Super. 177, 555 A.2d 129, 142 ([Pa. Super.] 1989).
. . . . Where, as here, the expert uses several sources to arrive at his or her opinion, and has noted the reasonable and ordinary reliance on similar sources by experts in the field, and has coupled this reliance with personal observation, knowledge and experience, we conclude that the expert’s testimony should be permitted.
Primavera, 608 A.2d at 520-21 (emphasis added).

The law is well-established that an expert may rely on hearsay statements in reaching an opinion. See Luzerne County Flood Prot. Auth. v. Reilly, 825 A.2d 779 (Pa. Cmwlth. 2003); see also In re Adoption of R.K.Y., 2013 PA Super 202, 72 A.3d 669, 677 (Pa. Super. 2013) (holding that the trial court properly admitted children’s out-of-court statements into evidence where child psychology expert “testified that reliance on interviews when preparing a psycho-sexual evaluation, including interviews conducted by colleagues, is ‘common practice in our field,’ . . . thus satisfying the basic prerequisites for admission under Rules 703 and 705”). Accordingly, precluding the Tarlinis’ Experts’ testimony because the Bonner Affidavit is hearsay and Bonner was not subject to cross-examination, under these circumstances, does not comport with precedential Commonwealth law.

In re Condemnation of Parcel ID No. 02-033-004 v. Lands of Tarlini, 185 A.3d 1177, 1187, 2018 Pa. Commw. LEXIS 122, *23, 2018 WL 1720829

What does this mean? Under 705, the Pennsylvania jury gets to hear/see everything the expert relied on, with a limiting instruction if requested or on the Judge’s own initiative. As to whether the trial judge may separately exclude the hearsay under 403 is a matter not discussed in Tarlini so that remains an open question; but a 403 analysis must be tempered by the absolute language in 705.