In State v. Butterfield, 2001 UT 59, 27 P.3d 1133, the Court held that a district court did not abuse its discretion in refusing to grant a mistrial after a witness testified that he had obtained the defendant's photograph from the Salt Lake County Jail. Id. The Court explained that the statement was not intentionally elicited, was "vague" and "fleeting," and the defendant could not point to evidence in the record suggesting that the jury had relied on the witness's statement. Id. The Court acknowledged the limitations inherent in eyewitness testimony, and we reiterated that because of these inherent deficiencies "trial courts are required to give a cautionary jury instruction when eyewitness identification 'is a central issue in a case and such an instruction is requested by the defense.'" In Butterfield the Court stated, "the calling of expert witnesses to testify as to matters which would apply to any crime or any trial does not in the true sense offer testimony of a witness who has knowledge of the facts of the case. Rather, it would be in the nature of a lecture to the jury as to how they should judge the evidence." Id. The Court then reiterated that a trial court's refusal to admit evidence would not constitute an abuse of discretion when proffered expert testimony would amount to a lecture to the jury as to how they should weigh testimonial evidence. Id. The Court upheld the exclusion of expert testimony because the expert's testimony "did not deal with the specific facts" of the case, but "would constitute a lecture to the jury about how it should judge the evidence." In Butterfield, the expert was not familiar with the defendant or the facts of the case and he would only have outlined for the jury the general principles of psychological knowledge which illuminate the problems of eyewitness performance. Id. In addition, there was "no showing that the excluded evidence would probably have had a substantial influence in bringing about a different verdict." Id.