In Minor v. United States, the Court of Appeals for the District of Columbia ruled that a psychological research expert witness met the three-prong Dyas standard and should have been allowed to testify regarding his eyewitness identification study expertise. The Court reasoned:

A. The Proffered Testimony Was Beyond the Ken of the Average Juror

In ruling on the first factor, the trial court opined that psychological research on eyewitness identification proffered by Dr. Fisher is “beyond the ken of the average lay person.” This is consistent with our recent observation in Benn II that “[d]espite the fact that jurors may be familiar from their own experience with factors relevant to the reliability of eyewitness observation and identification, … it cannot be said that psychological studies regarding the accuracy of an identification are within the ken of the typical juror.” Benn II, 978 A.2d at 1277 (alterations in original and internal quotation marks omitted). And while in Dyas we upheld a finding that such studies were not beyond the ken of the average juror, in Benn II we explained that “more recent studies … confirm” that “jurors generally lack knowledge about psychological studies regarding the accuracy of identifications.” Id. at 1278 n. 90.

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While finding that the studies were beyond the ken of the average juror, the trial judge also stated that it “[d]oesn’t mean that the conclusions of those articles are beyond the ken of the average lay person,” referring to the 2004 Hart survey. The judge was mistaken: it is precisely those conclusions and supporting research, we have recognized, that may be beyond a lay jury’s ken. As our remand order makes clear, citing Benn II, while average jurors may have a “passing familiarity with the potential problems surrounding eyewitness identification,” the conclusions and supporting research drawn from studies in this area are indeed “beyond the ken of most lay persons”; hence, they may be presented through expert testimony citing the findings and underlying research. The determinative question on the need for expert testimony is whether the jurors are “just as competent as the expert to consider and weigh the evidence and draw the necessary conclusions.” Adams v. United States, 502 A.2d 1011, 1021–22 (D.C.1986) (internal quotation marks omitted). Referencing the results of a juror survey, a survey conducted by a market and strategic research firm, does not provide the type of analysis needed to discern whether the average juror is just as competent as an expert like Dr. Fisher to weigh and consider the evidence relating to the reliability of eyewitness identifications. In sum, we have no hesitation in concluding that Mr. Minor’s proffer of Dr. Fisher’s expert testimony satisfied the first Dyas factor.

B. Dr. Fisher Has Sufficient Knowledge Such That His Opinions Will Probably Aid the Trier of Fact

The second Dyas factor requires that the party proffering the expert witness establish that the witness has “sufficient skill, knowledge, or experience in that field or calling as to make it appear that his opinion or inference will probably aid the trier in his search for truth.” Dyas, 376 A.2d at 832 (emphasis omitted). Here, the parties and the trial court agreed that Dr. Fisher’s professional background qualified him to testify as “an expert witness in the field of memory and eyewitness identification.” We see no reason to disturb that conclusion.

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C. The State of the Scientific Knowledge Permitted Dr. Fisher to Assert a Reasonable Opinion

The third Dyas factor permits a trial court to exclude expert testimony if the “state of the pertinent art or scientific knowledge does not permit a reasonable opinion to be asserted even by an expert.” Dyas, 376 A.2d at 832. When the expert testimony is based on “a novel scientific test or a unique controversial methodology or technique,” a so-called Frye test must be conducted, (Ricardo) Jones v. United States, 27 A.3d 1130, 1137 (D.C.2011) (internal quotation marks omitted), “under which scientific testimony is admissible only if the theory or methodology on which it is based has gained general acceptance in the relevant scientific community.” (John) Jones v. United States, 990 A.2d 970, 977 (D.C.2010) (citing Frye v. U.S., 293 F. 1013 (D.C.Cir.1923)). “Once a technique has gained such general acceptance, we will accept it as presumptively reliable and thus generally admissible into evidence.” (Ricardo) Jones, 27 A.3d at 1136 (internal quotation marks omitted).

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Accordingly, we are satisfied that Dr. Fisher’s proffered testimony satisfies the third Dyas prong because the theory or methodology on which it is based has gained broad general acceptance in the relevant scientific community.