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Updated 25 July 2010
  Friction Ridge Community Resource Page
This resource is designed to provide credible responses to questions about friction ridge examination. This information is not presented as exhaustive and does not address all aspects of the below topics. Comments and additional questions recommended for posting on this website are invited. Please contact the SWGFAST Website Committee with information or community resources for posting.

*newest information on top 

Date Category Item Abstract


7/10
IAI Resolution  IAI Resolution 2010-18. A ≈26K 2-page .pdf file of the official IAI resolution. On July 16th during the 2010 IAI Annual Educational Conference in Spokane, WA., the IAI passed resolution 2010-18 which rescinds the resolutions 1979-7 and 1980-5.
3/10 Position Statement Collaborative Testing Services, Inc. (CTS) issues a Statement on the use of Proficiency Testing Data for Error Rate Determinations. A ≈1,039K 3-page .pdf file that expands and clarifies the official position of CTS; that the use of CTS proficiency testing results should not be used a source for the determination of error rates for forensic science disciplines because results on "artifact samples" may not reflect casework level examination standards, truly "correct" or "incorrect" responses, or examiner performance in true casework situations.
3/10 Legal document US District Court for Massachusetts - Judge D.J. Gertner issues this Procedural Order for trace evidence. A ≈688K 3-page .pdf file of the Judge Nancy Gertner's Order for both parties in each case to identify in advance whether or not they are introducing trace evidence, whether or not they seek a Daubert/Kumho hearing, and the witnesses & exhibits required for the hearing.
2/10 Legal document California v. Greenwood Order regarding the consideration and denial by Judge Schnegg of an October 30, 2009 Motion to Exclude Fingerprint Evidence. A ≈18K 4-page .pdf file of the Judge Schnegg's Order in Superior Court of the United States of California for the County of Los Angeles, Case Number BA351185, denying the defendant's motion to exclude fingerprint evidence pursuant to People v. Kelly (1976) 17 Cal.3d 24.
2/10 Legal document California v. Greenwood Order regarding the consideration and denial by Judge Schnegg of an October 30, 2009 Motion to Exclude Fingerprint Evidence. A ≈688K 4-page .pdf file of the Judge Schnegg's Order in Superior Court of the United States of California for the County of Los Angeles, Case Number BA351185, denying the defendant's motion to exclude fingerprint evidence pursuant to People v. Kelly (1976) 17 Cal.3d 24.
9/09 Legal document US v. Rose Motion In Limine to Admit Testimony Without a Daubert Hearing, with Amicus Brief A ≈305K 40-page .pdf file of the US v. Rose: Government's Supplemental Motion In Limine to admit expert testimony of latent fingerprint identification without a Daubert hearing. CCB-08-0149, with the associated Amicus Brief.



Frequently Asked Questions
What is SWGFAST?
Answer: An organization that establishes consensus guidelines and standards for the forensic examination of fingerprints, palm prints and foot prints. It was established in 1995 as one of several forensic science Scientific Working Groups (SWG). The overall intent of Scientific Working Groups is to improve forensic science practices and build consensus amongst federal, state, local and private forensic laboratories and practitioners. Published SWG guidelines and standards are widely recognized by the forensic community, the courts, and the forensic laboratory accrediting bodies.
What are the legal rules for allowing expert witness testimony?
Answer: Federal and state courts have minimum qualifications for expert testimony. Federal Rules of Evidence 702 states:
If scientific, technical or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training or education, may testify thereto in the form of an opinion or otherwise, provided that (1) the testimony is based upon sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.
What are the U.S. Supreme Court decisions related to the Daubert, Kumho & Joiner "trilogy"?
Answer: The Daubert Opinion States that the trial judge must still screen scientific evidence to ensure it is relevant and reliable; “The focus, of course, must be solely on principles and methodology, not on the conclusions they generate.” Factors the court should consider include: Testing and validation, Peer review, Rate of error, “general acceptance”

Answer 2:
Kumho decided that the same criteria for Daubert applies to both technical and specialized knowledge referred to in FRE 702. Joiner expands the criteria to include the relevance and reliability of the scientific evidence.
What are the minimum qualifications for a Friction Ridge Examiner?
Answer: Legally, the judge decides who is qualified to present expert testimony.

Answer 2: SWGFAST established the following documents:
“Minimum Qualifications for Latent Print Examiner Trainees”
“Training to Competency for Latent Print Examiners”
“Quality Assurance Guidelines for Latent Print Examiners”

Answer 3: An individual who adheres to the above guidelines should be able to qualify as an expert in a court of law.
Is fingerprint examination a science?
Answer: Yes. Fingerprint examination is an applied science based upon the foundation of biological uniqueness, persistence, and empirical validation through observation. This is supported by the Daubert and Kumho decisions.
Is fingerprint examination reliable?
Answer: Yes. The scientific basis and methodology of fingerprint examination is reliable. The reliability of fingerprint examination is supported by the theories of biological uniqueness and persistence, probability modeling, and empirical data gained through over one hundred years of operational experience.
Can mistakes be made in fingerprint examination?
Answer: Yes. In any human endeavor, there is a potential for error. Adherence to SWGFAST guidelines for training to competency and quality assurance minimize the risk of human error.
Can an error rate be defined for friction ridge examination?
Answer: There are many definitions of error and many variables when calculating error rates. In regards to friction ridge examination error rate, the US Supreme Court in Daubert v. Dow states that, “…the focus, of course, must be solely on principles and methodology, not on the conclusions they generate.” Others claim that the method cannot be separated from the examiner and therefore they must be combined. Examples of discovered error rates, that an examiner may testify to, include: 1) personal erroneous identification rate, 2) laboratory erroneous identification rate, 3) estimated industry erroneous identification rate (based on the approximate number of detected errors; compared to the approximate number of examinations conducted to date).
Why were there so many errors in the 1995 & 1998 Collaborative Testing Service (CTS) latent print proficiency tests?
Answer: The CTS proficiency tests are not limited to only qualified fingerprint practitioners. There were no test controls over who took the test, the test environment, time constraints, or individual vs. group performance results. Other factors included but were not limited to the lack of understanding by the participants of the new testing process or use of its results. Non-answers, erroneous individualizations, missed individualizations, and clerical mistakes were considered equal errors to the test provider.
What is the standard for friction ridge identification (individualization)?
Answer: The standard for individualization is agreement of sufficient friction ridge details in sequence when the following conditions have been satisfied:
• Determined by a competent examiner, and
• Applied to a common area in both impressions, and
• Based on quantity and quality of the friction ridge details, and
• Absent any discrepancy, and
• Reproducible conclusion

Answer 2: SWGFAST has published standards for all conclusions.
How can two experts have different opinions on the same images?
Answer: Two experts having different levels of training, experience, and ability may reach conflicting conclusions. Two experts having the same level of training, experience, and ability should reach the same conclusion. There are three types of conflicting conclusions:

1) Individualization versus inconclusive
2) Exclusion versus inconclusive
3) Individualization versus exclusion

Conflicting expert opinions of individualization versus exclusion to the same friction ridge impression denotes an error on the part of one expert.
What is the definition of AFIS "lights-out" and does this process result in matches?
Answer: The term “lights-out” means an AFIS non-human process or workflow that is completely automated. This type of result is possible because of score-based algorithms that are able to automatically process some deliberately-recorded fingerprints that score above a pre-defined agency-specific threshold. Some agencies do not employ lights-out processes, and those that do have a wide range of score thresholds that result in human intervention.
Can AFIS always make automated fingerprint matches?
Answer: No. Often, deliberately recorded fingerprints are not high enough quality to achieve a score above a “lights-out” threshold. Additionally, latent prints currently return a ranked order of candidates based upon the position, location and direction of friction ridge features. A friction ridge examiner makes a decision of individualization or exclusion using the application of the ACE-V methodology which cannot be automated.
What is the National Academy of Sciences?
Answer: “The National Academy of Sciences (NAS) is an honorific society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare.”
What is the "NAS Report"?
Answer: The Strengthening Forensic Science in the United States: A Path Forward report was published in February, 2009 by the Committee on Identifying the Needs of the Forensic Sciences Community; Committee on Applied and Theoretical Statistics, National Research Council. It contained 13 recommendations to improve the forensic science disciplines.
Can fingerprints be identified with absolute certainty?
Answer: This is currently an issue that is heavily debated in the community. To reject the possibility of alternative hypotheses is unscientific because science is always open to new information. However, since fingerprint examination culminates with opinion testimony, the lack of the examiner’s doubt is often expressed as relative certainty in his or her conclusion. Current research is attempting to quantify distinctiveness and validate statistical and probability models that support the examiner’s conclusion. There are several online resources for additional information on this topic:
http://www.henrytempleman.com/
www.forensic.gov.uk
www.unil.ch/esc
Have statistical models been created for fingerprint identification?
Answer: Yes, there have been over 20 models proposed over the last century that are related to fingerprint identification. However, none of them take into account everything that an examiner would consider during the examination process and therefore each of them have limitations.
What is certification and why is it important?
Answer: Certification, as it relates to friction ridge examiners, involves assessing the knowledge, skill, and ability of an examiner to successfully complete an examination and demonstrate competency. Those lacking certification are not generally precluded from practicing or working in their respective disciplines.

Certification is important because it establishes a baseline of knowledge and allows external entities, who are not familiar with the discipline, to be assured of the skill level of the practitioner. The NAS report made strong recommendations for practitioners to achieve certification. The main external certifying body for friction ridge examiners is the International Association for Identification (IAI), and some agencies have internal certification programs.
Why is SWGFAST setting standards instead of guidelines?
SWGFAST was originally founded as a technical working group consisting of latent print examiners to create consensus guidelines as best practices within the friction ridge community. In the current climate, there has been a call by the fingerprint community, legal community and the NAS for more standardization. SWGFAST recognizes the importance of laboratory compliance with minimum standards, and is responding to this call by transitioning many of the SWGFAST guideline documents to standards.
Is my agency required to adopt SWGFAST standards? If we do we have to adhere to all sections of them?
Answer: No, because SWGFAST currently has no enforcement authority. However, SWGFAST guidelines and standards are widely recognized by the forensic community, the courts, and the forensic laboratory accrediting bodies. The U.S. Senate Judiciary Committee is currently considering implementing recommendations within the NAS report, including potential enforcement mechanisms for standards set by SWGFAST and the other Scientific Working Groups.
Are there any online references for addressing legal or daubert-like questions that might come up during testimony, and helpful answers for those questions?
How is the suitability of a friction ridge impression measured?
Answering the question of suitability requires that the purpose be defined. For example, whether a friction ridge impression is suitable for retention as evidence is a different question than whether it is suitable for identification.

The question of suitability also involves a subjective measurement of information. It is recognized that any scientific endeavor is subject to human interpretation. In friction ridge examination, what might appear as an objective threshold even has subjective elements. For example, requiring a minimum number of features to establish suitability for the purpose of identification may appear objective, but how an examiner defines a “feature” is still subjective. Scientific objectivity is achieved through the reproducibility of subjective conclusions by other examiners, within established parameters. Just because suitability thresholds are subjective doesn’t make them unreliable.
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