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G o o d   M o r n i n g !
Monday, June 14, 2004

The purpose of the Detail is to help keep you informed of the current state of affairs in the latent print community, to provide an avenue to circulate original fingerprint-related articles, and to announce important events as they happen in our field.

Breaking NEWz you can UzE...
compiled by Jon Stimac

Bungled Fingerprints Expose Problems at FBI   SEATTLE TIMES, WA  - June 8, 2004 ...The FBI says it is reviewing its practices and may issue new rules for the submission of photographs...

In Mayfield Case, Fingers Are Pointing   THE OREGONIAN, OR - June 9, 2004 ...the Spanish told the FBI that the fingerprint match was "conclusively negative."

Fingerprinting System May Help Crack Police Mysteries SOUTH BEND TRIBUNE, IN  - June 9, 2004 ...AFIS gives police a chance to find who a print belongs to when they didn't have a clue before...

Thumbprint 'Ploy' Costs Officer His School Job NEW ZEALAND HERALD, NZ  - June 12, 2004 ...a school resource officer who took thumbprints of  students he was interviewing about a theft no longer is employed by the city...

ANNOUNCEMENT: The IAI is interested in "one liner" historical snippets that reference the United States history of fingerprints over the first 100 years. Of special interest are snippets with containing historical points of interest that are not widely known. The individuals that offer up the most informative snippets will be rewarded by having their snippet acknowledged at the IAI conference in St. Louis, MO. Send your snippet to John Wilson by e-mail:


Last week Rhonda Boston related the need to consider standards and technology as opposed to deficiencies of the methodology and philosophy of fingerprint examination.  This week, Steve Everist brings us a summary of last week's National Public Radio broadcast regarding the Mayfield case and the reliability of fingerprint evidence.  The show is currently archived on the website of the National Public Radio (NPR) show, "The Connection" website.  To listen, visit the link:

Faulty Forensics
Aired: 6/10/2004
The Connection from WBUR Boston and NPR
Hosted by: Judy Swallow

"In the history of high-profile mistakes -- this was a humdinger. The FBI identified an Oregon attorney as the Madrid bomber and threw him in jail. The evidence? A 100 percent fingerprint match. But the FBI was 100 percent wrong -- the print wasn't Mayfield's. Some are saying this case highlights the fallibility of fingerprint evidence. We've all heard that no two fingerprints are alike, but no one knows if that's really true. Without uniform standards, critics say that fingerprint analysis is an art, not a science."

"Supporters say it is the most reliable system of evidence in the world. And prosecutors still tell juries if the prints match, you've got your man. Tell that to Brandon Mayfield."


Robert Epstein, a federal public defender in Philadelphia
Steven Wax, a federal public defender for the district of Oregon
Pat Wertheim, fingerprint analyst for the Arizona Department of Public Safety
Brandon Mayfield, a Portland, Oregon attorney.

The program began with Brandon Mayfield and his attorney, Steven Wax, reviewing the events surrounding his detention and eventual release in relation to the March 11, 2004 bombing of three Madrid, Spain train stations.

During this discussion Steven Wax said, regarding Ken Moses’ examination, “while Mr. Moses did find a match, that what is on the public record from him is that it was a very difficult process.  There was some distortion, some blotting out.  And that in order for him to reach what he called an ultimate determination of authenticity, he would have wanted to see additional information.”

Below I have highlighted some of the points made by Pat Wertheim and Robert Epstein during the moderated discussion on the reliability of fingerprint identification.

Robert Epstein began by saying that the Mayfield case highlights the questionable reliability of this (latent print) type of identification.  He further explained that three FBI examiners made the same erroneous identification, which was then confirmed by an independent examiner.  In other cases, the government’s contention was that the mistakes were the result of a bad practitioner.  But in this case all of the examiners are considered to be at the top of their field.

Epstein also declared that had it not been for the fortuity of having examiners in another country look at the print and being able to come up with a more compelling match, Mayfield would still be in jail today.  This point was made several times throughout the show.

He went on further to say that there is no idea how many erroneous identifications have been effected, but have not been detected.  The Cowans case was mentioned as an example of another case including an erroneous identification. 

Using the Llera Plaza case he highlighted that there has never been any scientific testing done, especially regarding “small, distorted, fragmentary” prints, and that there is no basis for examiners to make such a claim that all other fingers in the world could be excluded using prints of this nature.

Epstein later went on to say that science is the testing of a hypothesis and that the fundamental hypothesis in fingerprint analysis is, “That we can reliably make identifications from the type of small, distorted, fragmentary prints found at crime scenes.”  He further mentioned that no scientific testing has been done to try and establish this hypothesis and that the methodology of fingerprint analysis has never been tested.  He emphasized that there needs to be testing of the methodology to find out what the error rates are for different types of latent prints.

Epstein also proposed that there are no standards for practitioners including minimum competency and training, and that there should be standards put into play for examiners before they testify in court.

When a caller mentioned that DNA couldn’t be used to differentiate himself from his identical twin and that only fingerprints could be used, Epstein’s reply was that the example was that of a full fingerprint to a full fingerprint.  He related that this is not what we’re dealing with in criminal cases; that what we’re dealing with is the question is of the reliability of taking a small, distorted, fragment and being able to make an absolute identification from that.  This is where Epstein feels the issue of reliability comes into play.

He contends that testimony should not be permitted until testing as to how accurate fingerprint analysis really is.  He further mentions that this kind of testing is not very complicated and could be done, but there has been reluctance on the part of the government to undertake the test.  He asks why they are reluctant to go forward with testing that would give us the answers as to how accurate it truly is.

Epstein believes that judges are reluctant to throw out a technique that has been accepted for the past 100 years.  The evolution of fingerprint evidence being accepted came as a result of there being no counter-experts in the beginning.  This happened as a result of fingerprint analysis arising out of law enforcement and not academia.

He further went on to point out the 1995 Collaborative Testing Services 22% erroneous ID rate along with the IAI’s statistic of more than 50% failure rate for examiners taking the Latent Print Certification test.

His closing remarks are that there has to be some real science done that includes testing and standards.  He would be more comfortable if this were done.

Pat Wertheim started off early in the program by saying that he believes that the Mayfield erroneous identification is a "one-off"...  It is the first time in 79 years that we’ve heard of an erroneous ID at the FBI.  He doesn’t know how it occurred and is eager to hear from the FBI’s panel that is to investigate it. 

Wertheim believes that examiners should receive good training in all of the scientific underpinnings that relate to the science.  This should be followed by competency testing of the examiners.  He believes that underlying cause for the vast majority of errors that could be pointed out relate back to training or competency.  The science itself is reliable.    He feels that although most agencies have training programs and competency tests, unfortunately there are no national standards.  Examples were given of the UK and the Australia and New Zealand training programs.

Wertheim countered Epstein’s contention that scientific testing of a hypothesis hasn’t been done.  He related that over 100 years of empirical testing supports that uniqueness and permanence are the underlying foundation of fingerprint analysis.  He then began to discuss the methodology beginning with an analysis of a latent print and the three levels of detail.

He mentioned the psychological dynamics that are present in fingerprint analysis and that there needs to be a study of the psychology of human memory and its relationship to suggestion.  The process of recognition as it occurs in the human brain is a critical element of fingerprint identification that should be studied further.

Wertheim discussed the relationship between the quantity of detail and the quality of detail, and that their relation has to be sufficient to allow the individual examiner to reach the conclusion of a positive identification.  If there is an insufficient combination of the two in relation to each other, then the results would be inconclusive and the print would be of no value for identification.

Wertheim distinguished fingerprint identification as not being classified as pure science, but as an applied science – a forensic science.

He discussed issues with AFIS regarding database size and the possibility of close matches becoming more problematic.  The problem is in part to unqualified AFIS technicians who only look at location of points but do not look at the overall pattern and finer detail for exclusion.  There are cases published with 8-10 reasonably similar “points of identification.” But these can be easily distinguished once third level detail is analyzed.

Regarding historical acceptance of fingerprint evidence, Wertheim agreed that the standards for admissibility were initially much looser but have tightened significantly.  He states that fingerprints are still the most reliable means of identification and judges who continue to accept fingerprint testimony recognize this. 

Wertheim said that a fingerprint only proves that a person touched a surface.  It doesn’t prove that the person committed the crime.

In response to Epstein’s statistics regarding the IAI’s certification test, Wertheim added that the failure rate on the certification test is on missed ID’s rather than erroneous identifications.  It is far better to miss an ID than to make an erroneous ID.  It is better to let a guilty man go free than convict an innocent one.  He also commented on the 1995 CTS test where there appeared to be a manipulation of a print that was designed to trick examiners.  However he is ambivalent about the test because a qualified examiner should have recognized it as no match.

There were several callers to the show.  One of these callers was Iain McKie who shared some of his thoughts.  McKie agreed with Pat as to a need to test the proficiency of experts and that there is a lack of international standards.  He stated that this is an international problem, and that the international organizations such as the International Association for Identification and the Fingerprint Society disappear whenever these mistakes are made.  He further says that nothing will happen until these organizations stand up and throw these people out of the profession.

Pat Wertheim replied that the major organizations have not taken a position in regards to the (Shirley) McKie case.  Regarding international standards, Wertheim agreed in saying that application varies from country to country, if not in practice, at least in the way it is presented in court.

When another caller asked about a pattern changing over time, Wertheim used the analogy of marks on a balloon changing as a balloon is inflated.  There would be change, but the markings would still read the same.  He explained that the basal layer of the epidermis determines the details. The formation comes from inside the skin.  Details remain the same regardless of growth or aging.

Wertheim also countered Epstein’s statements that there have not been any studies done.  He mentioned the 1892 Study by Francis Galton where a crude model had been created.  He went on to say that over a dozen researchers had refined this model since 1892.  He also stated that statistics are not a good way to approach fingerprint identification by stating that uniqueness cannot be statistically defined.

Wertheim ended by mentioning Judge Pollak’s 2nd ruling.

“The reliability of the examiner through training, experience, and testing is the key to the reliability of the evidence they present in court.”

King County Sheriff’s Office
Seattle, Washington


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