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SCIENTIFIC CONCLUSIONS

Latent fingerprint practitioners have historically required absolute conclusions in their analysis of either positive identification or negative (exclusion). This practice has no scientific foundation, and no other forensic impression science limits the impartial analysis and the reporting of findings. IAI with the passage of resolution VII amended to V mandates that certified latent print examiners may not give qualified conclusions to their findings under the threat of their certification being revoked. This mandate is additionally required within the Scientific Working Group on Friction Ridge Analysis Study and Technology (SWGFAST) guidelines 2.1.5 Qualified Identifications, which states, "Friction ridge identifications are absolute conclusions. Probable, possible, or likely identification conclusions are outside the acceptable limits of the science of friction ridge identification."

I find it difficult to accept this position scientifically, as well as professionally. Scientifically, analysis by ridgeology requires no quantification and is primarily subjective. Ridgeology, and other methods of not quantifying, promotes a gray area analysis processes that has no standards in the application, but demands black and white findings in the conclusion.

Those agencies that follow scientific principle, demand black and white scientific analysis by quantification.  The analysis results are both black and white  conclusions, as well as [gray area] qualified conclusions. New Scotland Yard and Australia also share this position.

Martin Leadbetter, Head of Fingerprint Bureau, Cambridgeshire Constabulary, published in Fingerprint Whorld, Vol. 24 No 94, October 1998:
" Disclosure rules will play more and more a significant part on what information an expert is required to give an opinion. Retention of material could result in an expert being requested to assess a comparison, which does not reach a level where he/she can be positive. The answer to such a comparison can be:
A. The marks do not belong to the suspect
B. There is insufficient detail to reach any conclusion
C. The detail disclosed exactly matches the detail in the suspect's finger/palm prints but is insufficient to be positive as to identity. In such circumstances an expert can say that whilst no positive identification can be established the suspect can neither be excluded. An agreed term for this aspect will need to be established (Note: the Australians define it as Points Consistent)."

Christopher J. Coombes, Director of Identification Metropolitan Police Service, London England, reported at the February 1999 meeting of TWGFAST that, "Disclosure legislation enacted in 1997 requires that 'Points Consistent' analysis results must be reported at the outset, in the original analysis report."

Christopher Champod and Pierre A. Margot, Institut de Police Scientifique et de Criminologie, University of Lausanne, Switzerland, Reported at the 1995 Ne'urim Symposium, Computer Assisted Analysis of Minutiae Occurrences on Fingerprints:  Is dactyloscopic evidence anything else but absolute proof?

"In fact, there is no logical reason to suppress grey levels between white (exclusion) and black (identification).  Each piece of evidence is relevant if it tends to make the matter at issue more or less probable than otherwise.  Dactyloscopic evidence  can be combined with other (forensic or not) and fitted into the particular context of each case."

 "The refusal of qualified opinions in dactyloscopy is a policy decision [even if the distinction of the arguments (policy or scientific argumentation) is not so clear in the literature].  We think that the absence of extensive statistical data on fingerprint individuality is the main reason to prevent entering in the grey area."

Firearms and toolmark examiners render conclusions on their findings that are both absolute and qualified. The qualified conclusions report consistencies that are observed between the known and unknown, but fall short of being conclusive. The firearms/toolmark and latent print disciplines are both the same impression evidence science of analysis of individual characteristics. These individual characteristics are either created by man or by God.

In argument against the application of qualified conclusions, those opposed have readily admitted that if there are characteristics less than sufficient to identify but sufficient to exclude, an elimination opinion will be given. Using the same latent impression with the characteristics being consistent with a subject, these same individuals will call the latent impression NO VALUE. In science, the value of exclusion also has the value of inclusion.

In argument against the inclusion opinion, those opposed have stated that they do not want to unduly influence the jury with any possibility other than absoluteness. As impression evidence is strictly circumstantial, those that are opposed to the qualified conclusions have no legal or moral right to withhold evidence from the judge or the jury. To withhold evidence, flies in the face of the code of ethics that is adhered to by the scientific community.

If fingerprint identification is a science, then the scientific principles should be adhered to in all aspects of the analysis. If fingerprint practitioners do not want to follow scientific principles, then they should not call their discipline an exact science. I hail England and Australia for their sound decisions for full disclosure laws to report the truth of the evidence without imposing a misguided requirement to withhold evidence until the issuance of a court order to disclose it.