In the aftermath of the March 11, 2004, train bombing in Madrid,
Spain, personnel from the FBI Latent Print Unit performed a fingerprint
analysis and reported an individualization of a latent print with
a candidate print from an Integrated Automated Fingerprint Identification
(IAFIS) search. It was subsequently determined that the individualization
was in error, and the latent print was ultimately identified with
a different subject.
This report provides information regarding the corrective actions
the FBI Laboratory implemented upon recognizing the error, an outline
of significant events surrounding the FBI's fingerprint investigation,
and a synopsis of the comments by an international committee regarding
the erroneous fingerprint conclusion.
In accordance with American Society of Crime Laboratory Directors/Laboratory
Accreditation Board (ASCLD/LAB) guidelines and FBI Laboratory policies,
the FBI's Quality Assurance and Training Unit was notified upon
discovery of the Class I error. The ASCLD/LAB Accreditation Manual
defines Class 1 as, "The nature and cause of the discrepancy
raises immediate concern regarding the quality of the Laboratory's
work product." (ASCLD/LAB 2003)
The Unit implemented a corrective-action process that included the
- Suspending all casework assignments for the three FBI examiners.
- Reviewing the three examiners' casework for periods of
not less than two years.
- Appointing different examiners in the Laboratory to review the
case and prepare a revised report.
- Forming an external review committee.
- Implementing remediation measures, as deemed appropriate.
Additional corrective actions may be implemented.
International Review Committee
As part of the corrective-action process, an international committee
of distinguished latent print examiners and forensic experts was
formed. Their task was to review the analysis performed by the FBI
Laboratory and make recommendations that will help prevent this
type of error from occurring in the future. The Quality Assurance
and Training Unit established seven assessment objectives for the
committee to discuss.
The committee met at the FBI Laboratory at Quantico, Virginia, on
June 17 and 18, 2004. They were given access to the FBI case file,
case documentation, and Laboratory operational and quality assurance
manuals. The committee also met with the Laboratory personnel involved
in the case. The committee members prepared individual reports and
submitted them to Quality Assurance and Training Unit personnel.
This report is a synopsis of the major points made in the reports
submitted by the committee members.
The committee members consisted of Mr. Alan McRoberts, who is retired
from the Los Angeles County Sheriff's Department and is the
chairman of the Scientific Working Group on Friction Ridge Analysis,
Study, and Technology. Mr. McRoberts also served as the committee
chairman. Messrs. Ron Smith of Ron Smith and Associates, Bruce Grant
of New Scotland Yard, Gregoire P. Michaud of the Michigan State
Police, Chandler Lee Fraser of the Royal Canadian Mounted Police,
Frank Fitzpatrick of the Orange County Sheriff-Coroner Laboratory,
and Ken Smith of the U. S. Postal Inspection Service, Forensic and
Technical Services Division were the other committee members.
Mr. Frank Fitzpatrick was selected by the American Society of Crime
Laboratory Directors, and Mr. Ken Smith was selected by the International
Association for Identification to serve on the committee.
Mr. Juan Antonio Rodriguez San Roman of the Spanish National Police
Latent Print Unit served as a resource for the committee. Dr. Richard
Vorder Bruegge from the FBI's Investigative Technology Division
and Mr. Thomas Hopper of the FBI's Criminal Justice Information
Services Division also served as resources for the committee.
March 11, 2004
Train bombing occurred in Madrid, Spain.
March 13, 2004
Interpol Washington requested the analysis of latent fingerprints
that had been collected during the bombing investigation. An FBI Latent
Print Unit Chief assigned the case to a supervisory fingerprint examiner.
The Spanish National Police through Interpol Madrid sent electronic
images of the latent prints to the supervisor. Eight latent images
were of low resolution and without a scale. IAFIS searches were conducted
without effecting an identification. Latent Print Unit personnel asked
Interpol Washington to obtain higher resolution latent images with
a scale so that the ridge detail would be more visible and the latent
prints could be printed in their natural size to ensure the reliability
of IAFIS searches.
March 14, 2004
Interpol Washington submitted additional emails with the latent prints
and the known fingerprints of five individuals. The latent print images
were high resolution and displayed a scale. They were compared with
the five suspects insofar as possible, but no conclusion could be
made because the images of the known prints were of low resolution.
March 15, 2004
The supervisory fingerprint examiner encoded seven minutiae points
for the high-resolution image of latent fingerprint #17 and initiated
an IAFIS search.
March 16, 2004
The supervisory fingerprint examiner reviewed the candidate list.
The misidentified subject was the number four candidate. The supervisory
fingerprint examiner identified the subject on the basis of a comparison
using the on-screen images and examination of the high-resolution
digital printouts of the latent fingerprint and the known fingerprint
record from IAFIS. The Unit Chief was notified and reviewed the on-screen
The Unit Chief assigned the case to a verifier (a retired supervisory
fingerprint examiner working as a contractor). The verifier requested
original fingerprint cards from the FBI's Criminal Justice Information
March 19, 2004
The contractor verified the supervisory fingerprint examiner's
identification on the basis of his examination of the same high-resolution
digital copy of the latent fingerprint and the original fingerprint
cards that were forwarded to the Latent Print Unit by the Criminal
Justice Information Services Division.
The Latent Print Unit provided their initial report confirming that
latent fingerprint #17 was the same as the known prints of the number
four candidate. The Unit Chief provided this information by telephone
to Interpol Washington. The Unit Chief did not complete a thorough
examination of the identification prior to making the telephone call.
March 20, 2004
The Spanish National Police confirmed that latent fingerprint #17
was collected from a plastic bag.
An official FBI Laboratory report was issued identifying latent fingerprint
#17 with the number four candidate.
April 2, 2004
In response to an official request made by the Spanish National Police,
the FBI Legal Attache in Madrid provided copies of the known fingerprints
of the number four candidate to the Spanish National Police.
April 13, 2004
Spanish National Police fingerprint examiners arrived at an inconclusive
finding that the latent fingerprint discovered on a plastic bag belonged
to the number four candidate. Consequently, the Spanish requested
further clarification of the FBI Laboratory's analysis.
The FBI Legal Attache in Madrid informed the FBI of the Spanish National
Police report. Although the FBI Laboratory expressed confidence in
their findings, they agreed to prepare a detailed exhibit delineating
their analysis of the fingerprint in question. A three-page exhibit
was shipped overnight to the Spanish National Police.
April 21, 2004
The Unit Chief met with the Spanish National Police fingerprint examiners.
He demonstrated the comparison process using the images from the three-page
exhibit. He left the meeting thinking that the Spanish would continue
their comparison of latent fingerprint #17 to the number four candidate.
May 17, 2004
The FBI received a court order for latent fingerprint #17 from the
bag obtained in the Spanish investigation. The latent print was subsequently
provided to the United States Attorney's Office for submission
to the Court. According to the Court's order, the prints were
to be independently compared to the number four candidate's known
May 18, 2004
The Court appointed the independent examiner.
May 19, 2004
The Court's independent examiner reported in telephonic testimony
that latent fingerprint #17 was that of the number four candidate.
The Spanish National Police provided a letter to the FBI Legal Attache
in Madrid advising that the Spanish Laboratory had identified latent
fingerprint #17 as belonging to another person.
May 21, 2004
According to FBI Laboratory policies, Quality Assurance and Training
Unit personnel were notified of the situation.
Personnel from the FBI Latent Print Unit traveled to Madrid to resolve
the conflicting identifications. They were given access to all photographs
and the original evidence that bore latent fingerprint #17. (Latent
fingerprint #17 was no longer visible on the evidence because it had
been destroyed during subsequent fingerprint processing techniques.)
May 23, 2004
FBI Latent Print Unit personnel returned from Spain. An overnight
review of the case was conducted, and the error was recognized.
May 24, 2004
A corrective-action plan was initiated by the Laboratory's Quality
Assurance and Training Unit. The Unit took control of all related
evidence and documentation and formed an international committee to
review the procedures and factors.
May 27, 2004
A new team of FBI examiners, under the direction of a different Unit
Chief, began a comprehensive examination of the Madrid latent prints.
June 9, 2004
FBI Laboratory personnel traveled to Spain and obtained a photograph
from the original negative.
June 17-18, 2004
The international committee was convened and conducted a two-day review.
July 14, 2004
A final FBI Laboratory report was completed. This report excluded
the number four candidate and concurred with the Spanish National
Police individualization of latent fingerprint #17 to a different
August 2, 2004
The Quality Assurance and Training Unit's report regarding the
international committee was completed.
Committee Assessment Objectives and Synopses
1. Determine whether the process and procedures used in this
matter were appropriate.
The case assignment and general operational procedures were applied
in a manner that was consistent with the established FBI Latent
Print Unit's normal operational procedures and are consistent
with many other latent print units' operational procedures.
If the FBI had insisted on more information (e.g., an image with
scale for proper enlarging and an overall shot for orientation and
proper finger determination), this error may have been avoided.
(Object photographs that were available to the committee established
that the candidate's finger determination was not probable.)
This comment was not meant to mitigate the error. The error was
a "human" failure and not a methodology or technology
The prescribed methodology (Analysis, Comparison, and EvaluationVerification
or ACE-V) used for this examination was appropriate. It was the
examiners' application of this methodology that failed.
2. Determine where and how the examination faltered.
The IAFIS search of latent fingerprint #17 involved the encoding
of seven Level II details. The search results provided digit seven
of the fourth candidate. Upon reviewing the encoded detail and the
candidate's print, it was understandable why IAFIS provided
him as a candidate and why the initial examiner did not immediately
The power of the IAFIS match, coupled with the inherent pressure
of working an extremely high-profile case, was thought to have influenced
the initial examiner's judgment and subsequent examination.
This influence was recognized as confirmation bias (or context effect)
and describes the mind-set in which the expectations with which
people approach a task of observation will affect their perceptions
and interpretations of what they observe.
The apparent mind-set of the initial examiner after reviewing the
results of the IAFIS search was that a match did exist; therefore,
it would be reasonable to assume that the other characteristics
must match as well. In the absence of a detailed analysis of the
print, it can be a short distance from finding only seven characteristics
sufficient for plotting, prior to the automated search, to the position
of 12 or 13 matching characteristics once the mind-set of identification
has become dominant. This would not be an intentional misinterpretation
of the data, but it would be an incorrect interpretation nevertheless.
Once the mind-set occurred with the initial examiner, the subsequent
examinations were tainted. Latent print examiners routinely conduct
verifications in which they know the previous examiners' results
without influencing their conclusions. However, because of the inherent
pressure of such a high-profile case, the power of an IAFIS match
in conjunction with the similarities in the candidate's print,
and the knowledge of the previous examiners' conclusions (especially
since the initial examiner was a highly respected supervisor with
many years of experience), it was concluded that subsequent examinations
were incomplete and inaccurate. To disagree was not an expected
Additionally, this erroneous individualization was not made
by an examiner alone, but by an agency that for many years has considered
itself, rightfully so, as one of the best latent print units in
the world. Confidence is a vital element of forensics, but humility
is too. It was considered by the committee that when the individualization
had been made by the examiner, it became increasingly difficult
for others in the agency to disagree. This is supported because
the Latent Print Unit immediately entered into a defensive posture
when the Spanish National Police issued its statements that the
FBI was wrong.
Latent Print Unit personnel responded by preparing charted enlargements
using both Level II and Level III detail, and the Unit Chiefs traveled
to Spain to demonstrate to the Spanish National Police that the
FBI results were correct. This was interesting, considering that
the identification is filled with dissimilarities that were easily
observed when a detailed analysis of the latent print was conducted.
3. Assess the effects that digital image capture, compression,
and transmission on friction ridge detail may have had on this examination.
All of the committee members agree that the quality of the images
that were used to make the erroneous identification was not a factor.
4. Assess the general risks of conducting forensic examinations
in parallel with another agency.
If forensic examinations are conducted properly, there should be
no risks involved. Both agencies should come to the same conclusions.
When both agencies come to the same conclusion, the independent
conclusions become supportive. If the conclusions conflict (e.g.,
individualization versus exclusion), an error can then be discovered
and remedied (as in this case) to the benefit of all concerned.
If one examination is conclusive and the other examination is not
conclusive (e.g., as the result of conflicting procedural or legal
requirements), the examination that occurred by the agency with
legal jurisdiction will most likely prevail.
Based upon what occurred in this case, it appears that an agency
that is in a position to conduct parallel analyses with another
country should have a written protocol for sharing results and issuing
formal reports. If forensic examinations are conducted in accordance
with agency procedures and by well-trained fingerprint experts,
then there should be no risks involved. If those differences are
anticipated, there seems to be no inherent risk in conducting parallel
5. Identify policies, procedures, and guidelines to help avoid
a situation like this in the future.
The evidence surface, processing techniques, imaging resolution,
and compression are examples of things that should be known and
documented during the analysis stage of the examination.
Procedures that require descriptive documentation (graphic, textual,
or a combination of both) of the ACE-V process and blind verification
(i.e., previous results unknown to the verifier) should be implemented
on designated cases. This documentation should also note areas of
discrepancies in the prints and explanations for these discrepancies.
The original examiner's document should be sealed or withheld
from the verifier. The verifier would then conduct his or her examination
independently and document the characteristics and discrepancies
that were considered during the examination. Technical reviews of
each examiner's descriptive documentation would then reveal
any conflicting analyses and results, would require open communication
and discussion among examiners, and would require resolution.
The verifiers must do an independent and complete ACE-V examination
of each print that they are verifying. The verifiers must be willing
to oppose any examiner if they do not see the details needed to
effect the identification decision. The quality assurance program
should make examiners feel that they can disagree about any identification.
The examiners should be encouraged to step forward, without fear
of reprisal if they disagree. This part of the scientific method
must be institutionalized.
The current quality assurance rule requiring supervisor verification
of latent prints with less than 12 Level II characteristics needs
to be revised. A policy incorporating a definable quality and quantity
standard, rather than the current 12-point standard, needs to be
instituted for quality assurance. A high-point-count print of poor
quality may be more dangerous than some low-point-count, high-quality
latent prints. Points or any concept of points should be removed
from any policy manual. It may take years for this ingrained and
habitual methodology to change, but leaving the concept of points
anywhere in the manual will just delay it further.
A new quality assurance rule is needed regarding high-profile or
high-pressure cases. This would include supervisory verification
of conclusions regardless of the normal quality and quantity standard.
These and all supervisory verifications must be independent and
complete ACE-V examinations.
The case assignment process should be revised. Comparison ability
should be a primary consideration, especially in high-profile cases.
It must also be recognized that years on the job may not always
reflect ability. The organizational relationship should be considered
in making assignments. Daily examination practitioners should be
the primary analysts, and situations with a supervisor as a primary
examiner and a subordinate as a verifier should be avoided. (A subordinate
may not feel comfortable challenging the conclusion of a supervisor.)
Verifiers should be given challenging exclusions during blind proficiency
tests to ensure that they are independently applying ACE-V methodology
correctly and to detect skill atrophy.
A new approach to quality assurance and quality control needs to
be fostered. Personnel who are responsible for reviews of comparisons
need to be considered as checkers and not verifiers. They must be
trained to look for discrepancies as well as similarities. They
also need to be extensively trained to do checking on-screen as
well as with standard magnifiers.
Visual acuity is also a significant consideration. The visual acuity
of all examiners should be evaluated on a periodic basis. Although
there was no indication that the visual capability of the examiners
in this case was a factor, the early detection of visual problems
could help to avoid future errors.
There should be a written policy that clearly defines the protocols
to follow when dealing with international agencies. Included in
this policy should be language that dictates the reporting of results
through proper channels (administration) and states specifically
who is to be notified when dealing with terrorist cases.
6. Identify guidelines, if any, for the general latent print
community as a result of the lessons learned from this matter.
There has been reluctance for the majority of latent print units
to document the characteristics used in the examination by charting
latent prints and exemplars or providing a written description of
the areas of identification and discrepancies in designated cases
(i.e., high-profile cases or cases with latents of poor quality).
Such a document would provide a useful quality management tool to
determine what the examiner and verifier were using as a basis for
The recommendations in Section 5 apply to the general latent print
community. Additionally, agencies should adopt Scientific Working
Group on Friction Ridge Analysis, Study, and Technology and Scientific
Working Group on Digital Imaging guidelines for latent print analysis
and imaging as the backbone for their operational manuals. Erroneous
identifications, when found, need to be admitted and reported to
the agency as well as to the certifying and accrediting bodies.
Many agencies are slow to do this or refuse to admit that errors
have occurred. Admitting the error is the first step in the remediation
process. A remediation process must be included in the quality assurance
manual so that when it is needed, the process can begin promptly.
The FBI had this in place.
7. Determine additional assessment objectives that the panel
members deem appropriate.
The committee examined the latent impression and determined that
it did contain sufficient ridge detail to be correctly individualized.
An erroneous individualization is considered the most serious error
a latent print examiner can make in casework and cannot be tolerated
or minimized by an agency or the forensic community. The consequences
to any examiner for any such error should reflect the agency's
seriousness about issues involving quality assurance.
The consensus of the committee was that the failure was in the
application of the ACE-V methodology during this particular examination.
The committee also extended its appreciation to FBI Latent Print
Unit personnel for their forthright manner in accepting responsibility
and to the Laboratory, which took immediate steps to remedy the
situation. The candor of the personnel reporting to the committee
was appreciated and important to the credibility of the Laboratory.
The committee also recognized that although this erroneous conclusion
gained worldwide recognition and that it was very unsettling, the
FBI Laboratory set an excellent example in taking corrective actions.
On behalf of the FBI Laboratory, the author thanks the committee
members for reviewing this case and making recommendations. The
Laboratory is taking the committee's recommendations seriously
and believes that it will improve as a result of the committee's
American Society of Crime Laboratory Directors/Laboratory Accreditation
Board (ASCLD/LAB). ASCLD/LAB Accreditation Manual. American
Society of Crime Laboratoy Directors/Laboratory Accreditation Board,
Garner, North Carolina, 2003.