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Technology Related to Facial Identification. Dr Derek Carson University of Abertay d.carson@tay.ac.uk. 1970’s -Penry. Photofit – UK. The face is no more than the sum of its parts. Modern Systems. Computer based Electronic Facial Identification Technique (E-Fit). /Pro-fit.
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Technology Related to Facial Identification Dr Derek Carson University of Abertay d.carson@tay.ac.uk
1970’s -Penry Photofit – UK The face is no more than the sum of its parts.
Modern Systems • Computer based • Electronic Facial Identification Technique (E-Fit). /Pro-fit. • Benefits: Huge exemplar database Viewed in context Easier manipulation Different Race Databases No lines
E-fit Procedure • Stage 1 -Verbal Description - Cognitive Interview. • Stage 2. Aberdeen Index. • Stage 3. Choosing best exemplar Sizing Positioning • Stage 4. Use of paint package – artistic enhancement.
Bruce et al. (2000) • Morphed composite was always identified as well as the best individual likeness.
Evo-Fit – Dr Charlie Frowd – University of Lancaster Professor Peter Hancock – University of Stirling Professor Vicki Bruce- University of Newcastle Efit-V - Dr Chris Solomon – University of Kent at Cantebury. More Holistic Systems
Lancashire Constabulary. Derbyshire Constabulary. Northumbrian Constabulary. Current Pilot Testing
Simultaneous versus sequential presentation. Time taken to make decisions. Standard versus tailored models. Potential role for caricaturing? Vulnerable witnesses? Colour? 3 D capabilities? Recent Developments – Evo-Fit
Is it a Panacea? Forensic Trail evidence – Locard’s Exchange Principle – every contact leaves a trace. The image can be replayed and viewed by the arbiters of fact- the judge and jury. CCTV and Facial Mapping
Stills taken from University of Glasgow Psychology Department. Stimuli were the lecturing staff. 10 male and 10 female non-posed. Subjects were: 20 psychology students. 20 non psychology students. 20 police officers (13.5 years of service). Burton, Wilson, Cowan & Bruce (1999).
Each subject shown 10 video clips X 2. At test shown 20 high quality images.
Comparison of two images – obvious limitations due to quality of footage. Heads must be at similar angle. Comparison not based on numeric distance but of relative similarities. Role for statistics pertaining to the prevalence of a particular feature in a given population. Facial Mapping Techniques
Exculpatory evidence can be presented if marked unexplained differences are apparent. Similarity does not indicate identity unless the presence of unique identifiers can be established. Significance of similarity must be taken into account to support other types of evidence. Facial Mapping Techniques
Church V HMA [1996] Scots Law Requirement for corroboration. ¾ eyewitnesses provided positive ID Quality of footage disputed. At appeal two experts noted significant differences. R v Loveridge [2001] Consent from suspect is generally required for comparison footage.
Technological change is inevitable. Just because we can does not necessarily mean we should. We must always ensure that the roll out of technologies is given due consideration. Summary SUMMARY