In looking at the "Executive Summary Strengthening Forensic Science in the United
States: A Path Forward" I felt there was a glaring omission. While the report dealt with the inter-operability of the automated fingerprint identifications it did not address the database issues that should be a major concern with all local and state automated fingerprint identification systems. The poor quality fingerprint arrest card images in the search database, are a significant problem that can lead to missed and bad fingerprint identifications. A missed fingerprint identification allowing a criminal to avoid incarceration is a public safety issue. In the past this has resulted in additional criminal offenses to include homicide.
The reason that poor quality arrest card fingerprints are such a significant problem is because the number of missed and bad fingerprint identifications are significantly greater than the bad latent identifications and often directly impact regular citizens.
While the focus of this report was on the latent fingerprints, the number of useful latent fingerprints at a crime scene pales in comparison to the number of fingerprint cards processed in the course of a year. The FBI recently concluded that even when functioning well the IAFIS fingerprint system is 95% to 98% accurate. I would suggest, a realistic accuracy rate for state and local fingerprint systems would probably be closer to 90%. When this accuracy is combined with the large number of arrest and applicant fingerprint cards, you can see we are dealing with a large number of errors. Poor quality hardcopy fingerprint cards (criminal/non-criminal) increase the potential of error for the journeyman latent fingerprint examiners. A latent print is very often a poor quality image, when compared to a poor quality fingerprint card it increases the possibility of the latent fingerprint examiner making an incorrect conclusion. Since there is no minimum standard for declaring a latent fingerprint identification, examiners often declare an identification with less than 10 points of identification. 10 points, is the number of level II points of identification agreed to by all the examiners in the Mayfield bad identification. Again as noted in an earlier Blog all the latent fingerprint examiners in the Mayfield case, had significant training and experience.
The summary does have some good and important suggestions, which once implemented will improve the reliability of latent fingerprint identifications. The automated fingerprint database acceptance of poor quality fingerprint card images, will continue to produce both missed and bad identification arrest cards.
Bob McAuley
Dir. Operations/Training
Forensic Biometric Identification Solutions LLC.
Saturday, February 21, 2009
Monday, February 16, 2009
Madrid Bombing Bad Identification and it's Impact on current identification Procedures
There is no question the FBI latent fingerprint examiners as well as the court appointed latent fingerprint examiner had more training and experience than most fingerprint examiners employed in state and city identification laboratories. In looking at the report generated by the Office of the Inspector General (OIG) the reasons cited for the bad identification are very disturbing and should make every latent fingerprint examiner re-evaluate the criteria they use to make a determination of identification.
The report found " FBI fingerprint examiners relied in significant part on the relationship of "minutiae" or "points" within the prints. These points are places where individual ridges in the fingerprint end or split (ending ridges or bifurcations). These 10 features in Latent Finger Print 17 formed a constellation of points that was generally consistent with the constellation of points in the known fingerprints of both Mayfield and Daoud. The unusual similarity is reflected in the relative location of the points, the orientation of the ridges coming into the points, and the number of intervening ridges between the points. Although the OIG found no systematic study of the rarity of such an event, anecdotal reports suggest that this degree of similarity between prints from two different people is an extremely unusual circumstance."
As every latent fingerprint examiner knows, the minutiae/points is the level II detail. In the 70's as a latent fingerprint examiner, my agency required a minimum number of minutiae or points before a latent fingerprint examiner was allowed to testify in court to an identification. Many other agencies had similar policies. The question that this case brings up is what is the reliability of an identification with 10 or fewer minutiae or points ? I realize a lot has to do with the clarity and uniqueness of the minutiae, but when you're dealing with 10 or fewer points they are usually poor/marginal quality images.
The bias from the examplar tenprint card. " The OIG found that a significant cause of the misidentification was that the Latent Print Unit fingerprint examiners' interpretation of some features in Latent Finger Print 17 was adjusted or influenced by reasoning "backward" from features that were visible in the known fingerprints of Mayfield. This bias is sometimes referred to as "circular reasoning," and is an important pitfall to be avoided. Having found as many as 10 points of unusual similarity, the FBI fingerprint examiners began to "find" additional features in Latent Finger Print 17 that were not really there, but rather were suggested to the latent fingerprint examiners by features in the Mayfield prints. As a result of this process, murky or ambiguous details in Latent Finger Print 17 were erroneously identified as points of similarity with Mayfield's prints."
I'd like to think an experienced latent fingerprint examiner would not allow this bias to influence a decision, but even 4 experienced latent fingerprint examiners were influenced into a bad identification. The most effective way to guard against this would be to have an unbiased 3rd. party latent fingerprint examiner analyze the fingerprint without any knowledge of previous determinations.
Level III detail, "The OIG also found that the FBI latent fingerprint examiners gave significant weight to the purported agreement between extremely tiny details in Latent Finger Print 17 and Mayfield's fingerprints. These details, including shapes interpreted as individual pores, incipient dots between ridges, and ridge edges, are known as "Level 3" details. Because Level 3 details are so small, the appearance of such details in fingerprints is highly variable, even between different fingerprints made by the same finger. As a result, the reliability of Level 3 details is the subject of some controversy within the latent fingerprint community. The OIG found that none of the purported Level 3 features in Latent Finger Print 17 used to identify Mayfield corresponded to features in the known fingerprints of the true donor (Daoud). Thus, unlike the case with larger details, the examiners were not confused by any unusual similarity in Level 3 details on the fingerprints of Mayfield and Daoud. Rather, they apparently misinterpreted distortions in Latent Finger Print 17 as real features corresponding to Level 3 details seen in Mayfield's known fingerprints."
As a latent fingerprint examiner, I rely on Level II detail to make my determination of identification, I do use some Level III detail (ridge shape, etc.) in conjunction with the Level II (ending ridges, bifurcations, etc.) detail, during my comparison and evaluation of the prints. I have not had a situation where my determination of identification relied solely on Level III detail.
One discrepancy rule is followed by all latent examiners, if there is an unexplainable difference in the latent and tenprint fingerprint card, it must be declared a non-identification. "The FBI recognized that the entire upper left portion of Latent Finger Print 17 did not correspond with Mayfield's fingerprint. The examiners explained this difference as being the result of a separate touch, possibly by a different finger or a different person. This explanation required the examiners to accept an extraordinary set of coincidences. The OIG found that the support for this explanation was, at best, contradictory fingerprint examiners are governed by the "one discrepancy rule" in which a single difference in appearance between a latent print fingerprint and a known fingerprint must preclude an identification unless the examiner has a valid explanation for the difference. Latent fingerprint identifications are subject to a standard of 100 percent certainty. Implicit in this standard is the requirement that the examiner have equivalent certainty in the validity of each explanation for each difference in appearance between prints."
"The OIG also found that the FBI examiners failed to give adequate consideration to the incomplete nature of the agreement in points between Latent Finger Print 17 and Mayfield's fingerprint. As previously described, there was a constellation of as many as 10 points in LFP 17 that bore an unusual similarity to points in the Mayfield fingerprint. However, the limited clarity of Latent Finger Print 17 prevented, the latent fingerprint examiners from making an accurate determination of the type of many of these points (that is, whether they were ending ridges or bifurcations). The OIG found that many of the points utilized by the FBI to support the identification suffered from this shortcoming (ambiguity as to feature type), and that accordingly the "quality" of the agreement was inadequate to support the conclusion of identification." Apparently the latent fingerprint examiners allowed themselves to be influenced by each other and the tenprint fingerprint card.
What is clear from the Madrid bombing error is that even highly trained and experienced latent fingerprint examiners can make identification errors. Most latent fingerprint examiners testifying in court today, don't have near the training or experience of the 4 individuals above and often the identification is based on the opinion of only 1 latent fingerprint examiner. The automated fingerprint identification systems today are designed to find candidate fingerprints having the most minutiae arrangements similar to the encoded minutiae from the latent fingerprint. These candidates should include the correct match of the print (if it is in the database), but will also include the closest possible non-matches. These close non-match suspects require more fingerprint comparison experience than many of today's latent examiners have been able to acquire.
The report found " FBI fingerprint examiners relied in significant part on the relationship of "minutiae" or "points" within the prints. These points are places where individual ridges in the fingerprint end or split (ending ridges or bifurcations). These 10 features in Latent Finger Print 17 formed a constellation of points that was generally consistent with the constellation of points in the known fingerprints of both Mayfield and Daoud. The unusual similarity is reflected in the relative location of the points, the orientation of the ridges coming into the points, and the number of intervening ridges between the points. Although the OIG found no systematic study of the rarity of such an event, anecdotal reports suggest that this degree of similarity between prints from two different people is an extremely unusual circumstance."
As every latent fingerprint examiner knows, the minutiae/points is the level II detail. In the 70's as a latent fingerprint examiner, my agency required a minimum number of minutiae or points before a latent fingerprint examiner was allowed to testify in court to an identification. Many other agencies had similar policies. The question that this case brings up is what is the reliability of an identification with 10 or fewer minutiae or points ? I realize a lot has to do with the clarity and uniqueness of the minutiae, but when you're dealing with 10 or fewer points they are usually poor/marginal quality images.
The bias from the examplar tenprint card. " The OIG found that a significant cause of the misidentification was that the Latent Print Unit fingerprint examiners' interpretation of some features in Latent Finger Print 17 was adjusted or influenced by reasoning "backward" from features that were visible in the known fingerprints of Mayfield. This bias is sometimes referred to as "circular reasoning," and is an important pitfall to be avoided. Having found as many as 10 points of unusual similarity, the FBI fingerprint examiners began to "find" additional features in Latent Finger Print 17 that were not really there, but rather were suggested to the latent fingerprint examiners by features in the Mayfield prints. As a result of this process, murky or ambiguous details in Latent Finger Print 17 were erroneously identified as points of similarity with Mayfield's prints."
I'd like to think an experienced latent fingerprint examiner would not allow this bias to influence a decision, but even 4 experienced latent fingerprint examiners were influenced into a bad identification. The most effective way to guard against this would be to have an unbiased 3rd. party latent fingerprint examiner analyze the fingerprint without any knowledge of previous determinations.
Level III detail, "The OIG also found that the FBI latent fingerprint examiners gave significant weight to the purported agreement between extremely tiny details in Latent Finger Print 17 and Mayfield's fingerprints. These details, including shapes interpreted as individual pores, incipient dots between ridges, and ridge edges, are known as "Level 3" details. Because Level 3 details are so small, the appearance of such details in fingerprints is highly variable, even between different fingerprints made by the same finger. As a result, the reliability of Level 3 details is the subject of some controversy within the latent fingerprint community. The OIG found that none of the purported Level 3 features in Latent Finger Print 17 used to identify Mayfield corresponded to features in the known fingerprints of the true donor (Daoud). Thus, unlike the case with larger details, the examiners were not confused by any unusual similarity in Level 3 details on the fingerprints of Mayfield and Daoud. Rather, they apparently misinterpreted distortions in Latent Finger Print 17 as real features corresponding to Level 3 details seen in Mayfield's known fingerprints."
As a latent fingerprint examiner, I rely on Level II detail to make my determination of identification, I do use some Level III detail (ridge shape, etc.) in conjunction with the Level II (ending ridges, bifurcations, etc.) detail, during my comparison and evaluation of the prints. I have not had a situation where my determination of identification relied solely on Level III detail.
One discrepancy rule is followed by all latent examiners, if there is an unexplainable difference in the latent and tenprint fingerprint card, it must be declared a non-identification. "The FBI recognized that the entire upper left portion of Latent Finger Print 17 did not correspond with Mayfield's fingerprint. The examiners explained this difference as being the result of a separate touch, possibly by a different finger or a different person. This explanation required the examiners to accept an extraordinary set of coincidences. The OIG found that the support for this explanation was, at best, contradictory fingerprint examiners are governed by the "one discrepancy rule" in which a single difference in appearance between a latent print fingerprint and a known fingerprint must preclude an identification unless the examiner has a valid explanation for the difference. Latent fingerprint identifications are subject to a standard of 100 percent certainty. Implicit in this standard is the requirement that the examiner have equivalent certainty in the validity of each explanation for each difference in appearance between prints."
"The OIG also found that the FBI examiners failed to give adequate consideration to the incomplete nature of the agreement in points between Latent Finger Print 17 and Mayfield's fingerprint. As previously described, there was a constellation of as many as 10 points in LFP 17 that bore an unusual similarity to points in the Mayfield fingerprint. However, the limited clarity of Latent Finger Print 17 prevented, the latent fingerprint examiners from making an accurate determination of the type of many of these points (that is, whether they were ending ridges or bifurcations). The OIG found that many of the points utilized by the FBI to support the identification suffered from this shortcoming (ambiguity as to feature type), and that accordingly the "quality" of the agreement was inadequate to support the conclusion of identification." Apparently the latent fingerprint examiners allowed themselves to be influenced by each other and the tenprint fingerprint card.
What is clear from the Madrid bombing error is that even highly trained and experienced latent fingerprint examiners can make identification errors. Most latent fingerprint examiners testifying in court today, don't have near the training or experience of the 4 individuals above and often the identification is based on the opinion of only 1 latent fingerprint examiner. The automated fingerprint identification systems today are designed to find candidate fingerprints having the most minutiae arrangements similar to the encoded minutiae from the latent fingerprint. These candidates should include the correct match of the print (if it is in the database), but will also include the closest possible non-matches. These close non-match suspects require more fingerprint comparison experience than many of today's latent examiners have been able to acquire.
Bob McAuley
Dir. Operations/Training
Forensic Biometric Identification Solutions LLC.
Tuesday, February 10, 2009
"It takes 10 years of extensive training to excel in anything" Herbert Simon - Nobel Laureate
Scientific research has concluded that it takes eight-to-twelve years of training for a talented player/athlete to reach elite levels. This is called the ten-year or 10,000 hour rule, which translates to slightly more than three hours of practice daily for ten years (Ericsson, et al., 1993; Ericsson and Charness, 1994, Bloom, 1985; Salmela et al., 1998).
Does this apply to latent fingerprint examiners? and how does this impact latent fingerprint accuracy? I think everyone will agree that today latent fingerprint examiners have the opportunity to identify many more latent fingerprints than in the past, largely due to the automated fingerprint identification systems. I would estimate that 20 to 30% of the cases identified in my Lab. were cold hits ( fingerprint suspects produced by the automated fingerprint identification system). In addition to the increase in latent fingerprint identifications, there has been a decrease in image quality of the fingerprint cards housed in state and federal databases (tenprint cards). Many fingerprint cards are still poorly acquired and the fingerprint card printers on the automated systems often don't produce a high quality image for fingerprint comparison. What does that mean for the latent fingerprint examiner? it means that today there are many more difficult latent fingerprint comparisons for the latent examiner. Are there more missed and bad fingerprint identifications today, unfortunately, yes. In addition to the increase in the number of latent fingerprints developed and searched , the automated fingerprint identification system computers find unusually close non-matching fingerprint suspects. To make a determination of identification today it will require a latent fingerprint examiner that has reached " elite levels", the individual with 10,000 hrs of fingerprint comparison work and training. Unfortunately many of the local agencies don't have the resources to develop the latent fingerprint examiner to the elite levels, often they develop a fingerprint examiner that is good at many functions (a jack of all trades). There are many fingerprint identifications that can be done by journeymen fingerprint examiners. When the latent fingerprint lift and fingerprint card are both good, the fingerprint examiner with limited experience is capable making a good decision. The problem for the journeyman fingerprint examiner is when the print lacks clarity and they are required to determine a level of tolerance for discrepancies. The answer of course is more fingerprint experience and training before the latent examiner is allowed to testify in court. Is the problem of more fingerprint comparison work before allowing the fingerprint examiner to testify in court being addressed? Unfortunately it is not and we can expect more Boston PD and L.A. PD Lab. situations from other agencies in the future. Some fingerprint programs that do appear to work are the FBI and the larger states which do allow the latent examiner to reach the elite levels of experience before they are allowed to testify in court. The FBI requires that latent fingerprint examiners make in the neighborhood of 250,000 comparisons before they are ready to testify in court. The larger state agencies, New York as an example, develop fingerprint examiners through the tenprint system as part of a career ladder. It usually takes a fingerprint examiner close to 10 yrs to work up through the system to get a chance to be a latent fingerprint examiner. Both of these systems produce excellent latent fingerprint examiners. Most PD's and smaller states, because of budgetary issues, aren't able to develop elite level latent fingerprint examiners and will become the LA or Boston storyies in the future.
Does this apply to latent fingerprint examiners? and how does this impact latent fingerprint accuracy? I think everyone will agree that today latent fingerprint examiners have the opportunity to identify many more latent fingerprints than in the past, largely due to the automated fingerprint identification systems. I would estimate that 20 to 30% of the cases identified in my Lab. were cold hits ( fingerprint suspects produced by the automated fingerprint identification system). In addition to the increase in latent fingerprint identifications, there has been a decrease in image quality of the fingerprint cards housed in state and federal databases (tenprint cards). Many fingerprint cards are still poorly acquired and the fingerprint card printers on the automated systems often don't produce a high quality image for fingerprint comparison. What does that mean for the latent fingerprint examiner? it means that today there are many more difficult latent fingerprint comparisons for the latent examiner. Are there more missed and bad fingerprint identifications today, unfortunately, yes. In addition to the increase in the number of latent fingerprints developed and searched , the automated fingerprint identification system computers find unusually close non-matching fingerprint suspects. To make a determination of identification today it will require a latent fingerprint examiner that has reached " elite levels", the individual with 10,000 hrs of fingerprint comparison work and training. Unfortunately many of the local agencies don't have the resources to develop the latent fingerprint examiner to the elite levels, often they develop a fingerprint examiner that is good at many functions (a jack of all trades). There are many fingerprint identifications that can be done by journeymen fingerprint examiners. When the latent fingerprint lift and fingerprint card are both good, the fingerprint examiner with limited experience is capable making a good decision. The problem for the journeyman fingerprint examiner is when the print lacks clarity and they are required to determine a level of tolerance for discrepancies. The answer of course is more fingerprint experience and training before the latent examiner is allowed to testify in court. Is the problem of more fingerprint comparison work before allowing the fingerprint examiner to testify in court being addressed? Unfortunately it is not and we can expect more Boston PD and L.A. PD Lab. situations from other agencies in the future. Some fingerprint programs that do appear to work are the FBI and the larger states which do allow the latent examiner to reach the elite levels of experience before they are allowed to testify in court. The FBI requires that latent fingerprint examiners make in the neighborhood of 250,000 comparisons before they are ready to testify in court. The larger state agencies, New York as an example, develop fingerprint examiners through the tenprint system as part of a career ladder. It usually takes a fingerprint examiner close to 10 yrs to work up through the system to get a chance to be a latent fingerprint examiner. Both of these systems produce excellent latent fingerprint examiners. Most PD's and smaller states, because of budgetary issues, aren't able to develop elite level latent fingerprint examiners and will become the LA or Boston storyies in the future.
Friday, February 6, 2009
Brady vs. Maryland and Giglio vs. United States
Brady vs. Maryland and Giglio vs. United States make it clear that prosecutors must disclose to the defense information which bears on the reliability or veracity of witnesses. U.S. Supreme Court decisions have enforced the "Brady Rule" to include evidence maintained in personnel files. That means that when a latent, tenprint fingerprint examiner or crime scene specialist has intentionally communicated either verbally or in writing a deceptive documented statement or message, the prosecutor must inform the defense. Intentional deceptive action in a formal setting, such as testifying in court, during an internal affairs investigation or false evidence that tends to implicate another in a criminal act, should result in termination or permanent removal from any position where the individual would be called upon to be a witness in any court action. The situation becomes less clear when the individual's actions cannot be determined to be intentional. An internal investigation might determine there was no evidence of criminal intent. An example might be an individual makes a wrong determination on a fingerprint identity, or crime scene tech. associates the wrong individual(s) with the scene based on the evidence collected. It is clear that the individual's history would be discoverable and impact the credibility of that individual testimony. What is not clear is the impact on a unit if the supervisor of the unit has the credibility issue, example the Mayfield case. If the testimony will come from another individual in the unit, does the fact that the supervisor may be perceived as having a credibility issue have any bearing on the case ?
Sunday, February 1, 2009
Migration from 500ppi to 1,000ppi Fingerprint Search Database
While the decision to go to 1,000 ppi on fingerprint card capture was made some time ago it would appear that the bad economy has slowed, if not completely halted the migration. Most states have not migrated to 1,000 ppi. fingerprint card capture, so there are only a few states that find themselves in a situation where they are running automated fingerprint identification systems with search files consisting of both 500 ppi and 1,000 ppi fingerprint card images. The FBI does plan to move to 1,000 ppi fingerprint cards at some point in the future, but I would expect, that they are unable to make the move until all the large states have migrated to the 1,000 ppi fingerprint card capture systems. The issues confronting states from migrating will be cost issue's:
The FBI currently will accept the 1,000 ppi fingerprint images but they are storing the high resolution fingerprint images; they downsize the fingerprint image for searching and updating to the FBI fingerprint search database. So in effect the states submitting 1,000 ppi. fingerprint images are actually getting a 500 ppi. fingerprint search. This I would suspect was originally planned as a temporary solution by the FBI until all states moved to the higher resolution fingerprint systems.
So lets discuss some of the concerns with the migration from 500 to the 1,000 ppi fingerprint system. While getting a higher resolution fingerprint image should give agencies a more accurate fingerprint search is a logical assumption, the question is with the interim solution migrating to the higher resolution system will this assumption be true ? Running a system with fingerprint search database of 500ppi. and 1,000ppi. fingerprint images will create challenges for the fingerprint coders and matchers. The images are not the same size and they each are compressed using different compression algorithms with different ratios of compression. Will the interim fingerprint search system be able to match the current fingerprint system accuracy? The interim system would capture new fingerprint images at 1K ppi. and if an identification is made, replace the lower resolution fingerprint image with the new higher resolution fingerprint image. It is possible some states could manually convert all the hardcopy fingerprint cards in their database, reducing the number of lower resolution fingerprint cards left in the database as well as reducing the length of time they run the dual system. Remember so many fingerprint cards have been captured electronically over the last few years and these fingerprint images captured at 500 ppi cannot be interpolated up to 1,000 ppi. A big question is will the minutiae extraction algorithms and matcher algorithms be affected by having a mixed resolution database ? Each vendor,each agency, each version of afis software may be impacted a little or a lot. Remember the fingerprint minutiae extraction programs were developed for 500 ppi images and not for a dual resolution fingerprint systems. This is a question that has not been answered. I have not heard of any fingerprint system accuracy tests involving fingerprint systems with dual resolution fingerprint databases. I would also point out that most vendors test in a controlled situation with good quality fingerprint images to get the high fingerprint accuracy rates. In the real world the fingerprint accuracy rates are significantly lower because of poorly taken tenprints and partial latent images. In my experience the hit rate for latent fingerprint searches is seldom above 15%, this percentage is based on the number of unknown latent fingerprints entered into the system that are identified. Every examiner knows that getting a latent fingerprint hit is more dependent on the quality of the tenprint fingerprint image in the database than anything else. So whether the fingerprint card is captured at 500 ppi. or at 1K ppi the fingerprint accuracy, will be dependent on the quality of the fingerprint images captured at the livescan unit and how the matchers and coders handle dual fingerprint resolutions.
- Bandwidth for the higher resolution fingerprint card images.
- Conversion costs.
- Fingerprint livescan units are twice as expensive for the higher resolution units.
- System maintenance costs are a % of system cost so there is significant increase.
The FBI currently will accept the 1,000 ppi fingerprint images but they are storing the high resolution fingerprint images; they downsize the fingerprint image for searching and updating to the FBI fingerprint search database. So in effect the states submitting 1,000 ppi. fingerprint images are actually getting a 500 ppi. fingerprint search. This I would suspect was originally planned as a temporary solution by the FBI until all states moved to the higher resolution fingerprint systems.
So lets discuss some of the concerns with the migration from 500 to the 1,000 ppi fingerprint system. While getting a higher resolution fingerprint image should give agencies a more accurate fingerprint search is a logical assumption, the question is with the interim solution migrating to the higher resolution system will this assumption be true ? Running a system with fingerprint search database of 500ppi. and 1,000ppi. fingerprint images will create challenges for the fingerprint coders and matchers. The images are not the same size and they each are compressed using different compression algorithms with different ratios of compression. Will the interim fingerprint search system be able to match the current fingerprint system accuracy? The interim system would capture new fingerprint images at 1K ppi. and if an identification is made, replace the lower resolution fingerprint image with the new higher resolution fingerprint image. It is possible some states could manually convert all the hardcopy fingerprint cards in their database, reducing the number of lower resolution fingerprint cards left in the database as well as reducing the length of time they run the dual system. Remember so many fingerprint cards have been captured electronically over the last few years and these fingerprint images captured at 500 ppi cannot be interpolated up to 1,000 ppi. A big question is will the minutiae extraction algorithms and matcher algorithms be affected by having a mixed resolution database ? Each vendor,each agency, each version of afis software may be impacted a little or a lot. Remember the fingerprint minutiae extraction programs were developed for 500 ppi images and not for a dual resolution fingerprint systems. This is a question that has not been answered. I have not heard of any fingerprint system accuracy tests involving fingerprint systems with dual resolution fingerprint databases. I would also point out that most vendors test in a controlled situation with good quality fingerprint images to get the high fingerprint accuracy rates. In the real world the fingerprint accuracy rates are significantly lower because of poorly taken tenprints and partial latent images. In my experience the hit rate for latent fingerprint searches is seldom above 15%, this percentage is based on the number of unknown latent fingerprints entered into the system that are identified. Every examiner knows that getting a latent fingerprint hit is more dependent on the quality of the tenprint fingerprint image in the database than anything else. So whether the fingerprint card is captured at 500 ppi. or at 1K ppi the fingerprint accuracy, will be dependent on the quality of the fingerprint images captured at the livescan unit and how the matchers and coders handle dual fingerprint resolutions.
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