Duhaime's Law Dictionary


Facial Mapping Definition:

An identification technique which distinguishes unique facial characteristics of an individual.

Facial mapping is similar to fingerprint analysis in that it attempts to compare and distinguish the skeletal and other anatomical characteristics of a suspect from video or still camera images, by elimination, from others.

One international authority, quoted by Edmond , used these words to define facial mapping:

"The contents of two or more photographic, video or other images are compared to determine whether they depict the same person, or a photographic, video or other image is compared to a live (i.e. corporeal) target to determine whether the image is of the target individual. The process of comparison might involve talking measurements, noting characteristics, or other techniques, and might concentrate on the face alone or might include other parts of the body."

In R v Tang, the Supreme Court of New South Wales - Court of Criminal Appeal described the two most common approaches to facial mapping as follows, at ¶18:

"Morphology analysis (is a) feature by feature approach to evaluating faces, heads and bodies. It involves the comparison of two images – one from the crime scene and one of the suspect. It involves subdividing the face, head and body into components to obtain a thorough qualitative analysis and to determine visual similarities or differences.

"Photo-anthropometry is a technique that attempts to metrically compare the proportional relationships of one photo to another rather than determine absolute visual similarities, as is done in morphological comparisons. It involves the analysis of anthropometric landmarks, dimensions and angles [simply] to quantify facial characteristics and proportions from a photograph."

In R v Atkins (aka Atkins & Anor v R), a home invsion was caught on film but the resulting images were fuzzy. The facial mapping expert described his expertise as follows:

"His speciality is in facial features and their relationship to the underlying anatomy. For about 20 years he has specialised also in facial comparison. His report, and in due course his evidence, explained his approach and techniques as follows:

  • It is well known that a number of persons may share the same proportions of face, and similar features; two people may have faces which appear indistinguishable to his examination; accordingly his comparison cannot make a positive identification, although it may make a definite exclusion because there may be irreconcilable differences in features;
  • He uses a computer with high definition to compare images; the (video) footage is examined stopping every second;
  • Two faces being studied are (a) compared for their horizontal and vertical proportions, (b) compared by examination and description of the shape and form of their features (this known as morphological examination), and (c) may be measured for both distances and angles between features, using a grid superimposed on the faces. The first and third exercises require comparable camera angles and perspective; the second does not, but any difference in perspective must be allowed for.
  • If those tests do not eliminate the suspect, the photographs can also be superimposed one on the other, and part of one face can be substituted for the same part of the other, and juxtaposed with the remainder of the other, both as further checks."
"(There were) factors which could affect the reliability of his exercise. Many related to the quality of the photographs and the various things which could affect that. Another was pixilation, which is or can be image compression when a photograph is transferred to a computer. Two more of his stated risk factors were the possibility that two different people may appear indistinguishable; and the fact that there exists no database of facial characteristics."

REFERENCES:

  • Edmond, G. and others, Law's Looking Glass: Expert Identification Evidence Derived from Photogenic and Video Images, 20 Current Issues Crim. Just. 337 (2008-2009)
  • Molloy, Jill, Facial Mapping Expert Evidence, 74 J. Crim. L. 20 (2010)
  • R v Atkins, [2009] EWCA Crim 1876
  • R v Gardner, [2004] EWCA Crim 1639
  • R v Gray, [2003] EWCA Crim 1001
  • R v Mitchell, [2005] EWCA Crim 731
  • R v Tang, [2006] NSWCCA 167

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