ARTICLE VII. OPINIONS AND EXPERT TESTIMONY

Rule 701. Opinion Testimony by Lay Witnesses.

 If a witness is not testifying as an expert, testimony in the form of an opinion is limited to one that is:

 (a)  rationally based on the witness’s perception;

 (b)  helpful to clearly understanding the witness’s testimony or to determining a fact in issue; and

 (c)  not based on scientific, technical, or other specialized knowledge within the scope of Rule 702.

   This rule is identical to F.R.E. 701.

   On January 17, 2013, the Rules of Evidence were rescinded and replaced. See Pa.R.E. 101, Comment. Within Article VII, the term ‘‘inference’’ has been eliminated when used in conjunction with ‘‘opinion.’’ The term ‘‘inference’’ is subsumed by the broader term ‘‘opinion’’ and Pennsylvania case law has not made a substantive decision on the basis of any distinction between an opinion and an inference. No change in the current practice was intended with the elimination of this term.

   Official Note

   Adopted May 8, 1998, effective October 1, 1998; amended November 2, 2001, effective January 2, 2002; rescinded and replaced January 17, 2013, effective March 18, 2013.

   Committee Explanatory Reports:

   Final Report explaining the November 2, 2001, amendments published with the Court’s Order at 31 Pa.B. 6384 (November 24, 2001).

   Final Report explaining the January 17, 2013 rescission and replacement published with the Court’s Order at 43 Pa.B. 651 (February 2, 2013).

 A witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise if:

 (a)  the expert’s scientific, technical, or other specialized knowledge is beyond that possessed by the average layperson;

 (b)  the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue; and

 (c)  the expert’s methodology is generally accepted in the relevant field.

   Pa.R.E. 702(a) and (b) differ from F.R.E. 702 in that Pa.R.E. 702(a) and (b) impose the requirement that the expert’s scientific, technical, or other specialized knowledge is admissible only if it is beyond that possessed by the average layperson. This is consistent with prior Pennsylvania law. See Commonwealth v. O’Searo, 466 Pa. 224, 229, 352 A.2d 30, 32 (1976).

   Pa.R.E. 702(c) differs from F.R.E. 702 in that it reflects Pennsylvania’s adoption of the standard in Frye v. United States, 293 F. 1013 (D.C. Cir. 1923). The rule applies the ‘‘general acceptance’’ test for the admissibility of scientific, technical, or other specialized knowledge testimony. This is consistent with prior Pennsylvania law. See Grady v. Frito-Lay, Inc., 576 Pa. 546, 839 A.2d 1038 (2003). The rule rejects the federal test derived from Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993).

   Pa.R.E. 702 does not change the Pennsylvania rule for qualifying a witness to testify as an expert. In Miller v. Brass Rail Tavern, Inc., 541 Pa. 474, 480-81, 664 A.2d 525, 528 (1995), the Supreme Court stated:

    The test to be applied when qualifying a witness to testify as an expert witness is whether the witness has any reasonable pretension to specialized knowledge on the subject under investigation. If he does, he may testify and the weight to be given to such testimony is for the trier of fact to determine.

   Pa.R.E. 702 does not change the requirement that an expert’s opinion must be expressed with reasonable certainty. See McMahon v. Young, 442 Pa. 484, 276 A.2d 534 (1971).

   Pa.R.E. 702 states that an expert may testify in the form of an ‘‘opinion or otherwise.’’ Much of the literature assumes that experts testify only in the form of an opinion. The language ‘‘or otherwise’’ reflects the fact that experts frequently are called upon to educate the trier of fact about the scientific or technical principles relevant to the case.

   Official Note

   Adopted May 8, 1998, effective October 1, 1998; Comment revised April 1, 2004, effective May 10, 2004; rescinded and replaced January 17, 2013, effective March 18, 2013.

   Committee Explanatory Reports:

   Final Report explaining the January 17, 2013 rescission and replacement published with the Court’s Order at 43 Pa.B. 651 (February 2, 2013).

 An expert may base an opinion on facts or data in the case that the expert has been made aware of or personally observed. If experts in the particular field would reasonably rely on those kinds of facts or data in forming an opinion on the subject, they need not be admissible for the opinion to be admitted.

   This rule is identical to the first two sentences of F.R.E. 703. It does not include the third sentence of the Federal Rule that provides that the facts and data that are the bases for the expert’s opinion are not admissible unless their probative value substantially outweighs their prejudicial effect. This is inconsistent with Pennsylvania law which requires that facts and data that are the bases for the expert’s opinion must be disclosed to the trier of fact. See Pa.R.E. 705.

   Pa.R.E. 703 requires that the facts or data upon which an expert witness bases an opinion be ‘‘of a type reasonably relied upon by experts in the particular field. . . .’’ Whether the facts or data satisfy this requirement is a preliminary question to be determined by the trial court under Pa.R.E. 104(a). If an expert witness relies on novel scientific evidence, Pa.R.C.P. No. 207.1 sets forth the procedure for objecting, by pretrial motion, on the ground that the testimony is inadmissible under Pa.R.E. 702, or Pa.R.E. 703, or both.

   When an expert testifies about the underlying facts and data that support the expert’s opinion and the evidence would be otherwise inadmissible, the trial judge upon request must, or on the judge’s own initiative may, instruct the jury to consider the facts and data only to explain the basis for the expert’s opinion, and not as substantive evidence.

   An expert witness cannot be a mere conduit for the opinion of another. An expert witness may not relate the opinion of a non-testifying expert unless the witness has reasonably relied upon it in forming the witness’s own opinion. See, e.g., Foster v. McKeesport Hospital, 260 Pa. Super. 485, 394 A.2d 1031 (1978); Allen v. Kaplan, 439 Pa. Super. 263, 653 A.2d 1249 (1995).

   Official Note

   Adopted May 8, 1998, effective October 1, 1998; Comment revised September 11, 2003, effective September 30, 2003; rescinded and replaced January 17, 2013, effective March 18, 2013.

   Committee Explanatory Reports:

   Final Report explaining the September 11, 2003 revision of the Comment published with the Court’s Order at 33 Pa.B. 4784 (September 27, 2003).

   Final Report explaining the January 17, 2013 rescission and replacement published with the Court’s Order at 43 Pa.B. 651 (February 2, 2013).

 An opinion is not objectionable just because it embraces an ultimate issue.

   Pa.R.E. 704 is identical to F.R.E. 704(a).

   F.R.E. 704(b) is not adopted. The Federal Rule prohibits an expert witness in a criminal case from stating an opinion about whether the defendant did or did not have a mental state or condition that constitutes an element of the crime charged or a defense. This is inconsistent with Pennsylvania law. Commonwealth v. Walzack, 468 Pa. 210, 360 A.2d 914 (1976).

   Official Note

   Adopted May 8, 1998, effective October 1, 1998; rescinded and replaced January 17, 2013, effective March 18, 2013.

   Committee Explanatory Reports:

   Final Report explaining the January 17, 2013 rescission and replacement published with the Court’s Order at 43 Pa.B. 651 (February 2, 2013).

 If an expert states an opinion the expert must state the facts or data on which the opinion is based.

   The text and substance of Pa.R.E. 705 differ significantly from F.R.E. 705. The Federal Rule generally does not require an expert witness to disclose the facts upon which an opinion is based prior to expressing the opinion. Instead, the cross-examiner bears the burden of probing the basis of the opinion. Pennsylvania does not follow the Federal Rule. See Kozak v. Struth, 515 Pa. 554, 560, 531 A.2d 420, 423 (1987) (declining to adopt F.R.E. 705, the Court reasoned that ‘‘requiring the proponent of an expert opinion to clarify for the jury the assumptions upon which the opinion is based avoids planting in the juror’s mind a general statement likely to remain with him in the jury room when the disputed details are lost.’’) Relying on cross-examination to illuminate the underlying assumption, as F.R.E. 705 does, may further confuse jurors already struggling to follow complex testimony. Id.

   Accordingly, Kozak requires disclosure of the facts used by the expert in forming an opinion. The disclosure can be accomplished in several ways. One way is to ask the expert to assume the truth of testimony the expert has heard or read. Kroeger Co. v. W.C.A.B., 101 Pa. Cmwlth. 629, 516 A.2d 1335 (1986); Tobash v. Jones, 419 Pa. 205, 213 A.2d 588 (1965). Another option is to pose a hypothetical question to the expert. Dietrich v. J.I. Case Co., 390 Pa. Super. 475, 568 A.2d 1272 (1990); Hussey v. May Department Stores, Inc., 238 Pa. Super. 431, 357 A.2d 635 (1976).

   When an expert testifies about the underlying facts and data that support the expert’s opinion and the evidence would be otherwise inadmissible, the trial judge upon request must, or on the judge’s own initiative may, instruct the jury to consider the facts and data only to explain the basis for the expert’s opinion, and not as substantive evidence.

   Official Note

   Adopted May 8, 1998, effective October 1, 1998; rescinded and replaced January 17, 2013, effective March 18, 2013.

   Committee Explanatory Reports:

   Final Report explaining the January 17, 2013 rescission and replacement published with the Court’s Order at 43 Pa.B. 651 (February 2, 2013).

 Where the court has appointed an expert witness, the witness appointed must advise the parties of the witness’s findings, if any. The witness may be called to testify by the court or any party. The witness shall be subject to cross-examination by any party, including a party calling the witness. In civil cases, the witness’s deposition may be taken by any party.

   Pa.R.E. 706 differs from F.R.E. 706. Unlike the Federal Rule, Pa.R.E. 706 does not affect the scope of the trial court’s power to appoint experts. Pa.R.E. 706 provides only the procedures for obtaining the testimony of experts after the court has appointed them.

   In Commonwealth v. Correa, 437 Pa. Super. 1, 648 A.2d 1199 (1994), abrogated on other grounds by Commonwealth v. Weston, 561 Pa. 199, 749 A.2d 458 (2000), the Superior Court held that the trial court had inherent power to appoint an expert. 23 Pa.C.S. §  5104 provides for the appointment of experts to conduct blood tests in paternity proceedings.

   See also Pa.R.E. 614 (Court’s Calling or Examining a Witness).

   Official Note

   Adopted May 8, 1998, effective October 1, 1998; rescinded and replaced January 17, 2013, effective March 18, 2013.

   Committee Explanatory Reports:

   Final Report explaining the January 17, 2013 rescission and replacement published with the Court’s Order at 43 Pa.B. 651 (February 2, 2013).

   The provisions of this Rule 706 rescinded and replaced January 17, 2013, effective in sixty days, 43 Pa.B. 620. Immediately preceding text appears at serial pages (299644) to (299645).