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Rule 702. Testimony by experts

If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence of to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise, if (1) the testimony is sufficiently based upon reliable facts or data. (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case. [New matter is underlined]

In Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993), the Supreme Court held that when expert evidence based upon "scientific knowledge" is offered at trial, the judge, upon proper motion by a litigant who challenges the admissibility of the testimony, should act as a gatekeeper and first determine whether the proffered evidence is "reliable"--whether it is evidence that can be trusted to be scientifically valid.

In the aftermath of Daubert, a number of courts had to address the unresolved issue whether the Daubert factors by which reliability was to be tested should also be applied to experts offering opinion testimony that was not based on clearly identified scientific principles, but which sprung from "technical or other specialized knowledge." Since the clear majority of informed opinion seemed to favor applying a Daubert-like standard to all expert opinion testimony, the Advisory Committee on the Rules of Evidence endorsed that requirement by including the above language in the proposed amendment that is due to become effective on December 1.

After the drafters first proposed this Amendment, the Supreme Court clarified its Daubert opinion in the case of Kumho Tire Co. V. Carmichael, 119 S.Ct. 1167 (1999) by mandating that the trial judges' duty to act as gatekeepers, charged with insuring that only reliable expert opinion evidence be admitted, apply to all forms of expert testimony. The Court thus approved the above proposed amendment, which had already been widely publicized prior to the Court's decision in Kumho Tire.

In the Committee Note that follows the Amended language of Rule 702, the drafters emphasized again the non-exclusive checklist courts are to use in judging whether proffered scientific expert opinion testimony meets the Daubert criteria of reliability:

"The specific factors explicated by the Daubert Court are: (1) whether the expert's technique or theory can be or has been tested -- that is, whether the expert's theory can be challenged in some objective sense, or whether it is instead simply a subjective, conclusory approach that cannot reasonably be assessed for reliability; (2) whether the technique or theory has been subject to peer review and publication: (3) the known or potential rate of error of the technique or theory when applied; (4) the existence and maintenance of standards and controls; and (5) whether the technique or theory has been generally accepted in the scientific community."

In Kumho Tire, the Court recognized that these same factors might not be applicable to all forms of expert opinion testimony, and stressed that these factors constituted not mandates but flexible guidelines, and that courts could look at other factors that, depending on the particular circumstances of a case, were likely to permit an assessment of the reliability of the nonscientific expert opinion testimony offered to the tribunal. The Court also specifically declared that the gatekeeping function of trial judges "applies not only to testimony based on 'scientific' knowledge, but also to knowledge based on 'technical' and 'other specialized' knowledge."

While in 1993 the Daubert Court was explicit in stating that the trial judge's focus in determining reliability was to be directed solely toward examining the "principles and methodology, not on the conclusions they generate," in the later case of General Electric v. Joiner, 522 U.S. 136 (1997) the Court backpedaled from this announced position and recognized that "conclusions and methodology are not entirely distinct from one another." The problem of considering both methodology as well as the conclusion is also covered by the language of the proposed amendment to Rule 702, in that it directs a trial court to determine not only whether the methods used by an expert and the principles upon her analysis rests have been determined to be reliable, but also whether "the witness has applied the principles and methods reliably" to the facts that are in controversy in the particular case.

II. Another amendment to the Federal Rules of Evidence pertains to disclosing the bases upon which an expert opinion is based.

Rule 703. Bases of Opinion Testimony By Experts

The facts or data in the particular case upon which an expert bases an opinion or inference may be those perceived by or made known to the expert at or before the hearing. If of a type reasonably relied upon by experts in the particular field in forming opinions or inferences upon the subject, the facts or data need not be admissible in evidence in order for the opinion or inference to be admitted. Facts or data that are otherwise inadmissible shall not be disclosed to the jury by the proponent of the opinion or inference unless the court determines that their probative value in assisting the jury to evaluate the expert's opinion substantially outweighs their prejudicial impact. [Added matters are underlined.]

When the Federal Rules of Evidence were first enacted in 1975, one of the important changes to the common law rules of evidence was that under Rule 703 experts could base an opinion not only on facts which were in evidence, but also on facts that were not in evidence, and even on facts which might not even be admissible if they were offered at trial, as long as these underlying facts dealt with the kind of information on which similar experts would rely in making non-litigation-oriented professional judgments. Thus, under the Federal Rules of Evidence, the emphasis shifted, away from the admissibility of the facts upon which an expert's opinion was based, to the reliability of these facts as determined by the profession in arriving at professional judgments independent of litigation. The Amendment above is designed to clarify that just because an opinion may be based on inadmissible evidence, that does not make the underlying information therefore admissible.

Of course, the amendment only applies to the "proponent" of certain evidence. The opponent or contestant may freely inquire into the underlying facts upon which an expert's conclusion is based.

III. A change was also made in Rule 701, dealing with opinion evidence by ordinary fact witnesses.

Rule 701. Opinion Testimony by Lay Witnesses

If the witness is not testifying as an expert, the witness' testimony in the form of opinions or inferences is limited to those opinions or inferences which are (a) rationally based on the perception of the witness, (b) helpful to a clear understanding of the witness' testimony or the determination of a fact in issue, and (c) not based on scientific, technical, or other specialized knowledge within the scope of Rule 702. [Added material is underlined.]

Lay witnesses may be permitted to offer opinion evidence in cases where ordinary persons would typically relate their recollections of events in a conclusory matter. Thus, courts permit lay witnesses to offer opinions like, "he appeared to be drunk," "he was going much, much faster than the 10 MPH speed limit," "it smelled like rotten eggs," etc. The amendment made clear that the reliability requirements first imposed by Daubert and thereafter incorporated into the Amended Rule 702 will not be evaded by offering the opinions of experts as "lay opinions" rationally based on perception. Thus, expert testimony is to be filtered through the reliability sieve of Rule 702, and cannot be offered in the guise of lay opinions.

This requirement is also designed to prevent experts from avoiding compliance with the expert disclosure requirements of the Federal Rules of Civil Procedure (Rule 26) and the Federal Rules of Criminal Procedure (Rule 16) by presenting opinion testimony of experts as lay opinions.

The focus in the amendment is on "lay testimony" and "expert testimony." It is possible for an witness to have information available on which he or she could provide lay as well as expert opinion evidence. For example, a person is generally permitted to testify to the value of his own business without needing to be an appraiser or Realtor, because the specialized knowledge that the owner has gives her an adequate basis of knowledge upon which to determine the value. What the amendment clarifies is that if the "testimony" of the witness is subject to the reliability requirement of Rule 702--as where we sought to establish the value of property not through its owner but through a qualified expert such as an appraiser-- then only Rule 702 governs its admissibility. This would require, probably, a showing that the appraiser had arrived at an opinion by using methods of evaluation that were generally accepted as reliable, and that the appraiser was qualified in that field.