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Illinois Supreme Court Clarified Admissibility of Opinion Testimony Under Frye Standard

01 Mar 2002

For some time, the Frye standard has been the unequivocal test for the admission of expert testimony in Illinois. However, Illinois appellate jurisdictions have not uniformly applied the test. The proper method of applying the Frye test to determine the admissibility of expert testimony was set forth in the Illinois Supreme Court™s recent holding of Zachary Donaldson v. Central Illinois Public Service Co., No. 89679, 2002 WL 254042 (Feb. 22, 2002).

The Frye standard, commonly referred to as the general acceptance test, dictates that expert testimony is only admissible at trial if the methodology or scientific principle upon which the opinion is based is sufficiently established to have gained general acceptance in the particular field in which it belongs. The Court made clear that general acceptance does not concern the expert™s ultimate conclusion. Instead, the focus is entirely upon the underlying methodology used to generate the opinion. Therefore, even if a novel conclusion is reached, the opinion is still admissible if based on generally accepted methodology.

In order to obtain a finding of general acceptance for a methodology used by an expert, universal acceptance in the field is not required. When determining whether a scientific procedure is generally accepted in the scientific community, the issue is consensus versus controversy over a particular technique. However, the existence of a dispute within the field does not preclude a finding that a procedure is generally accepted.

The Frye test is meant to exclude methods new to science that undeservedly create a perception of certainty when the basis of the evidence or opinion is actually invalid. The trial judge will determine whether the scientific procedure at issue is generally accepted and the jury is to determine whether it will accept the experts conclusions based upon that technique.

The Court found the trial judge™s role is more limited that a gatekeeper of expert opinion testimony. Instead, a judge should apply the Frye test only when the scientific principle, technique, or test relied upon by an expert to support opinions is new or novel. Once a particular test, principle, or technique has been found to have gained general acceptance in the particular scientific community by a court, its general acceptance in subsequent litigation is presumed. Examples of scientific principles that have gained the presumption of general acceptance are certain types of DNA testing, fingerprinting and blood testing.

The Supreme Court™s opinion in Zachary Donaldson rejected the Frye-plus-reliability standard applied in Whiting v. Coultrip, 324 Ill.App.3d 161, 755 N.E.2d 494, 258 Ill.Dec. 111 (3d Dist. 2001); and Harris v. Cropmate Co., 302 Ill.App.3d 364, 706 N.E.2d 55, 235 Ill.Dec. 795 (4th Dist. 1999).

Based upon the application of the Frye test and past decisions addressing extrapolation, the Supreme Court of Illinois found that when a controlled medical study is impossible or impractical, the technique of extrapolation to determine a causal relationship is generally accepted under Illinois law. The Court affirmed a $3.2 million dollar verdict based upon a causal connection between exposure to coal tar and the lethal condition of neuroblastoma. Although no medical study has ever linked the two, plaintiffs™ experts were allowed to draw a causal relationship based upon the extrapolation of statistical evidence.


Contact:   Michael J. Scotti, III


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