Difference between revisions of "Unvalidated or Improper Forensic Science"
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===Data of erroneous fingerprint identification=== | ===Data of erroneous fingerprint identification=== | ||
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| + | There is a worrying number of examples involving erroneous fingerprint identification. | ||
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| + | * '''Cowans case''' | ||
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| + | Cowans was convicted of armed assault with intent to murder in 1998 after being accused of shooting a police officer. He was linked to the crime by the testimony of two eyewitnesses, one being the victim, but also from a fingerprint found on a mug from which the assailant had drunk. Fingerprint experts testified that it was Cowan's fingerprint. He was sentenced to 35 years of imprisonment. When he managed to collect enough money, he had the evidence tested by DNA. | ||
| + | The DNA did not match his, yet he had already served SIX YEARS in prison before he was eventually released. | ||
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| + | * Photographs of ten pairs of latent and inked fingerprints were sent out to fingerprint bureaus in England and Wales requesting that experts with ten or more years of experience undertake the ten comparisons independently of each other. Nine of the pairs that were supplied were taken from past casework of Scotland Yard. Six of these pairs were properly identifiable to one another, while the other three were considered borderline cases. The tenth pair provided by the researchers consisted of two prints that were made by different fingers. The examiners were asked to decide whether each of the pairs were identifiable and, if so, the number of corresponding points of similarity that could be seen. The variation in the 130 responses was extraordinary. For example, the number of points of comparison that the examiners reported in one of the pairs ranged from ten to forty. There was also considerable disagreement as to whether identifications could properly be effectuated. On one of the pairs, 44% of the examiners found that an identification could be made, while 56% said that it could not | ||
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| + | * '''Proficiency Tests''' - While these exams do not constitute controlled scientific studies, they nevertheless do provide some indication of the proficiency, or lack thereof, of examiners. | ||
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| + | 1. '''CTS 1995 Latent Fingerprint Proficiency Test'''- Of the 156 examiners who participated, only sixty-eight (44%) were able to correctly identify the five latent prints that should have been identified, and to correctly note the two elimination latent prints that were not to be identified. Even more significantly, thirty-four of these examiners (22%) made erroneous identifications on one or more of the questioned prints for a total of forty-eight misidentifications. | ||
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| + | 2. '''CTS 2007 Latent Fingerprint Proficiency Test'''- The test materials included two latent prints produced by people whose known prints were not provided. Yet four examiners incorrectly matched one of the latent prints to one of the known's, three matched a latent to an innocent suspect, and a fourth one matched a latent to an innocent bank employee. | ||
