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Thursday, January 30, 2020

Facial Comparison

FISWG's Facial Comparison Overview describes Morphological Analysis as "a method of facial comparison in which the features of the face are described, classified, and compared.  Conclusions are based on subjective observations." ASTM's E3149 − 18, Standard Guide for Facial Image Comparison Feature List for Morphological Analysis, provides practitioners a 19-table guide of features to aid the examiner in the classification of features within images / videos of faces.

Why bring this up?

A fairly recent case in California highlights the need for practitioners to be not only aware of the consensus standards but to employ them in their work. In People v Hernandez (link), the unpublished appellate ruling describes the work of an analyst employing a novel technique which was excluded at the trial level.

"Upon review, we conclude [name omitted] proffered comparisons were based on matter of a type on which an expert may not reasonably rely, and they were speculative. The trial court acted well within its authority as a gatekeeper in essentially determining that [name omitted] was not employing the same level of intellectual rigor of an expert in the relevant field. Notably, the theories relied upon by [name omitted] were new to science as well as the law, and he did not establish that his theories had gained general acceptance in the relevant scientific community or were reliable."

Given FISWG's Facial Comparison Overview, there is a consensus on the general methods for Facial Comparison:

  • Holistic Comparison 
  • Morphological Analysis
  • Photo-anthropometry
  • Superimposition

The analyst's choice?

"Asked how he would compare the images, [name omitted]  explained he would use, in part, Euclidean geometry. He admitted this was a technique that other people did not use. Also, he used what he called Michelangelo theory — [name omitted]'s technique of taking away portions of a distorted and/or blurred digital image to reveal the true features of the person in the iPhone video still and Exhibit 8—and an unnamed and unexplained technique for looking at bad images. [name omitted] thought his margin of error was five-to-eight percent."

"On cross-examination, [name omitted] agreed he was "somewhat unique" in using Euclidean geometry in image analysis and comparison. He did not have a scientific degree or a degree in Euclidean geometry. When asked if his use of Euclidean geometry had been subjected to scientific and peer view, he stated, "Sometimes, but not in this case because it's a theorem to understand my logic. I'm not drawing lines. . . . [¶] . . . [¶] I'm using a theory. . . . I'm defending my logic with a theory in geometry[.]" On an as-needed basis, [name omitted] used a member of his staff for peer review. The prosecutor inquired if [name omitted] was aware of anyone using Euclidean geometry in the forensic analysis of photographs like him, and he replied, "By name? No."

"[name omitted] was asked if he had made any effort "to distinguish between artifacts and properties of the individuals depicted" in Exhibit 8. He replied, "No. Not in the report." He was then asked if he tried to make a distinction in his analysis. He said, "As best as . . . one could possibly do, but there's quite a bit of pixilation on that image."

In California, there's a lot of precedent on the admission of expert testimony. This case cites Sargon v USC (link) in addressing the issue of the appropriateness of the Trial Court's exclusion of the analyst's testimony and work.

"[In California,] the gatekeeper's role `is to make certain that an expert, whether basing testimony upon professional studies or personal experience, employs in the courtroom the same level of intellectual rigor that characterizes the practice of an expert in the relevant field.' [Citation.]" (Sargon, supra, 55 Cal.4th at p. 772.)"

"Based on the foregoing, we conclude [name omitted]'s comparisons were properly excluded. His method was full of theories and assumptions, and he ignored some or all of the artifacts at different points. Simply put, his opinion was not based on matter of a type on which an expert may reasonably rely. Beyond that, because [name omitted] essentially confused artifacts for features, his opinion was speculative."

The ruling goes on to note relevant cases to support the conclusion that the exclusion was appropriate. As such, it's a good reference.

But to the point, why make up a new technique when there's plenty of guidance out there regarding photographic comparison / facial comparison? For Morphological Analysis, you can easily translate the ASTM's guide into a spreadsheet that can be used to document features and locations. Yes, all of the current methods necessarily result from subjective observations. Likewise, conclusions are based upon those observations and as such, should be adequately supported.

If you're involved in a case where photographic comparison / facial comparison is at issue, feel free to contact me regarding a review of the evidence and/or the work done previously, or by opposing counsel's analyst. It's important to note that giving one's work to "a member of [one's] staff for peer review" is not actually a "peer review," it's a technical review. If you'd like an actual peer review, contact me today.

Likewise, if you want to learn this amazing discipline, we regularly feature classes on photographic comparison in Henderson, NV. We can also bring the class to you.

Have a great day, my friends.

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