Home About Us Laboratory Services Forensic Science Communications Back Issues July 1999 Presentations from the International Symposium on Setting...
This is archived material from the Federal Bureau of Investigation (FBI) website. It may contain outdated information and links may no longer function.

Presentations from the International Symposium on Setting Quality Standards for the Forensic Community (Part 5; Forensic Science Communications, July 1999)


July 1999 - Volume 1 - Number 2


Presentations at the
International Symposium on Setting Quality Standards for the Forensic Community
San Antonio, Texas

May 3-7, 1999

Part 5

The following abstracts of the presentations are ordered alphabetically by authors’ last names.

Identification Criteria and Statistics in Fingerprint Evidence
S. B. Meagher
Federal Bureau of Investigation
Washington, DC

Friction ridge (fingerprints, palm prints, and footprints) identification specialists have provided expert opinion testimony for almost 100 years, and the use of fingerprints as a means of personal identification has been accepted worldwide. The basis for individualization is that the friction ridge arrangement for each finger, palm, and foot is unique and permanent. The identification criteria for a latent print comparison with a known ten-print exemplar is a composite of several factors, each having a different relevance for each comparison conducted. The comparison process, therefore, is both qualitative and quantitative. The three levels of friction ridge detail must be understood and applied appropriately to each comparison. An understanding of the physiology of friction skin coupled with the effects of several variables, such as the substrate material, processing technique, and pressure distortion, provides the expert with the knowledge needed to properly conduct a comparison and effect an identification.

The identification criteria consists of four main elements:

  • There must be an agreement of friction ridge formations. At a minimum, Level 1 and Level 2 detail must correlate. Level 3 detail can be used as necessary and is generally relied upon during the comparison process, but commonly not during the identification decision unless the quantity of Level 2 detail is minimal and the quality of Level 3 detail provides sufficient clarity.
  • The sequential relationship of all elements must be the same. The ridge flow of Level 1 detail and the type, direction, and relationship of each Level 2 detail (as well as Level 3 detail, when used) must be the same.
  • The prints must be void of any unexplainable discrepancy. If any discrepancy occurs, then the specialist must provide a logical explanation based on the several factors influencing the appearance of the friction ridges in question.
  • There must be sufficient uniqueness to individualize. This element requires an assessment of both the quality and quantity of information contained in both the unknown print and the known exemplar.

There have been numerous attempts over the years to establish a statistical probability to fingerprint identification, with results reflecting a wide range of answers. The primary focus of these studies has been to determine how little of Level 2 detail is required in order to effect an identification. No known studies to date have taken into account all of the identification criteria elements described previously. Regardless, most studies using even a limited amount of Level 2 detail have shown probabilities exceeding the world’s population.

Case in point: A study was performed using advanced algorithms developed for the FBI’s Integrated Automated Fingerprint Identification System (IAFIS) project. The study consisted of 50,000 left-sloped loops of white males. Each fingerprint was matched against the 50,000 files, which resulted in over 2.5 billion comparisons. The resultant statistical probability is that there is a chance of 1 in 1097 that two fingerprints from different fingers will have the same friction ridge arrangement.

A second study was conducted that reduced the fingerprint to 21.7 percent of the total area. This area reflects the average area from a sample of 300 latent fingerprints. The resultant statistical probability is that there is a chance of 1 in 1016 that two fingerprints with as few as four Level 2 detail characteristics from different fingers will have the same friction ridge arrangement. In both studies the probability is less than the population of the world (estimated to be 5.9 billion) times ten fingers, or 59 billion fingerprints. That is, the chance of two persons having the same fingerprint exceeds all the world’s population of fingers.

Back to index


Challenges of Quality Assurance and Leadership
in the Forensic Laboratory
R. S. Murch
Federal Bureau of Investigation
Washington, DC

In recent years, quality assurance (QA) has been widely discussed and acted upon from a few important perspectives within the forensic laboratory community. Most commonly, the foci for forensic QA primarily have been external laboratory accreditation and the development and recognition of standards by the relevant portions of the crime laboratory community. Recently, I proposed a more holistic view of QA, which takes into consideration many more aspects of the underlying philosophy; laboratory practice; personnel performance; operational processes; complex environmental, measurement, and accountability thresholds necessary to effectively conduct high quality, consistent, responsive, and defensible forensic science. I also argued that the burden for the design, implementation, and maintenance of this new QA perspective rests with crime laboratory management. Leadership and learning are permeating components of successful crime laboratory QA in my model. Current leadership concepts were discussed in the contexts of crime laboratory management and QA.

Back to index


Development of Empirical Testing of Numerical Criteria
for the Identification of Striated Toolmarks
J. E. Murdock

Bureau of Alcohol, Tobacco and Firearms
Walnut Creek, California

There has been a small but persistent voice in the forensic wilderness asking for the development of objective criteria for the identification of striated toolmarks. This presentation is a discussion of the chronology of the forms of these requests.

Empirical testing conducted at the California Department of Justice, California Criminalistics Institute (CCI) is described. This testing helped lead to the development of the following conservative numerical criteria for the identification of striated toolmarks:

  • In three-dimensional toolmarks, when at least two different groups of at least three consecutive matching striae appear in the same relative position, or one group of six consecutive matching striae are in agreement in an evidence toolmark compared to a test toolmark.
  • In two-dimensional toolmarks when at least two groups of at least five consecutive matching striae appear in the same relative position, or one group of eight consecutive matching striae are in agreement in an evidence toolmark compared to a test toolmark.

For these criteria to apply, however, the possibility of subclass characteristics must be ruled out. Subclass characteristics are defined and examples shown.

And finally, this presentation contains a review of recent studies that have validated these numerical criteria.

Back to index


EPA’s Experience With Quality Management Standards
for Forensic Measurement Activities
K. E. Nottingham and B. Hughes

Environmental Protection Agency
Washington, DC

In the prosecution of both civil and criminal enforcement cases, the Environmental Protection Agency (EPA) has developed a system for gathering and analyzing evidentiary samples of environmental media. This is forensic science under a broader definition than is traditionally practiced in police laboratories. Although the same levels of proof need to be met as in police laboratories, the types of samples—usually water, soil, or hazardous wastes—and the analytes, which are usually environmental pollutants or characteristics that the EPA has deemed hazardous, are different.

Another difference between traditional police analyses and environmental forensics are the methods published by the different media offices: water, air, hazardous wastes, pesticides, and toxic chemicals. Each of these offices took a different approach to quality management by issuing different methods, sometimes reflecting different philosophies about how to mandate quality. For instance, the Office of Water issued prescriptive methods that had to be followed, whereas the Office of Solid Waste issued methods as guidance that showed that there was, at least, one way that the analyte could be determined.

All the media offices, except the Pesticides and Toxics Office, tended to issue quality control guidance with the method, thereby creating method-specific quality control criteria instead of project- or objective-specific criteria. The Pesticides and Toxic Office tended to operate in a manner more in keeping with how I understand that a police laboratory operates or how my employer, the National Enforcement Investigation Center (NEIC), operates, in that they expect a data package to contain enough quality control to stand on its own without referring back to a validated method. The Pesticides and Toxic Office operates this way because they usually deal with a relatively small number of determinations on many new and unique compounds.

This presentation deals with EPA’s efforts towards implementing a unified Quality Management System (QMS) and with similar efforts of NEIC, the laboratory of the Office of Enforcement and Compliance Assurance. The topics addressed include operating within that system and enhancing that system to address forensics:

  • The EPA Quality Management System,
  • The National Environmental Laboratory Accreditation Conference,
  • The National Voluntary Laboratory Accreditation Program for Asbestos, and
  • NEIC’s efforts towards Accreditation for Environmental Measurements and Forensics.

Back to index


Evolution of Proficiency Testing as a Quality Assurance Tool in the Forensic Sciences
J. L. Peterson
University of Illinois at Chicago
Chicago, Illinois

A variety of scientific, legal, and societal forces have converged on the forensic science community in the past 30 years to require that it take steps to assure the quality of its procedures and its scientific results. As the forensic science community was just beginning its rapid growth in the late 1960s, allegations of high error rates in the clinical laboratory testing field led the government to impose standards and proficiency testing as the gold standard to verify competency in the profession. The LEAA-sponsored studies of proficiency testing in the 1970s revealed serious deficiencies in the crime laboratory field that led, in turn, to the implementation of laboratory accreditation and efforts to certify laboratory personnel in the 1980s. The introduction of forensic DNA typing into the courts in the 1980s created even greater pressure on the forensic community to develop guidelines for ensuring quality results and to create bodies such as TWGDAM. Proficiency testing, again, played a major role in the development of DNA standards as a set of tests of commercial laboratories revealed sample handling errors.

The 1990s witnessed the growth of a wide range of quality assurance programs in forensic laboratories, as accreditation, certification, and methods evaluation efforts began to mature and take root. Several national investigating bodies endorsed the reliability of forensic DNA typing but also recommended continuing review of results through proficiency testing. The watershed U.S. Supreme Court decision of Daubert v. Merrell Dow Pharmaceuticals, Inc. in 1993 focused attention on the reliability of proffered evidence and specifically cited consideration of error rates as one criteria for judging the admissibility of a scientific technique. A published review of crime laboratory proficiency test results over the period 1978–1991 found a mix of results, with areas such as fiber, paint, glass, and body fluid mixtures revealing a relatively high rate of unacceptable responses. In the area of DNA typing, on the other hand, recent proficiency test results indicate laboratories are performing consistently and reliably. It appears certain that proficiency testing will continue to be a central component of the forensic science profession’s efforts to ensure the highest quality work product.

Back to index


ASCLD/LAB Accreditation Process:
Are You Up to the Challenge?
D. M. Plautz
Garner, North Carolina

The Crime Laboratory Accreditation Program, established by the American Society of Crime Laboratory Directors (ASCLD), is a voluntary program in which any crime laboratory may participate to demonstrate that its management, operations, personnel, procedures, equipment, physical plant, security, and health and safety procedures meet established standards. The program is managed by the American Society of Crime Laboratory Directors, Laboratory Accreditation Board (ASCLD/LAB), which is responsible to the Delegate Assembly composed of the directors of all accredited laboratories. Accreditation is part of a laboratory’s quality assurance program, which should also include proficiency testing, continuing education, and other programs to help the laboratory give better overall service to the criminal justice system. The process of self-evaluation, which leads to accreditation, is in itself a valuable management tool for the crime laboratory director.

ASCLD/LAB has adopted the following four objectives that define the purposes and nature of the program:

  • Improve the quality of laboratory services provided to the criminal justice system,
  • Develop and maintain criteria that can be used by a laboratory to assess its level of performance and to strengthen its operation,
  • Provide an independent, impartial, and objective system by which laboratories can benefit from a total operational review, and
  • Offer to the general public and to users of laboratory services a means of identifying those laboratories that have demonstrated that they meet established standards.

The underlying questions to be examined during an inspection to determine the quality of the laboratory are the following:

  • What is it you say you are doing?
  • Are you doing what you say you are doing?
  • Have you documented what you say you are doing?

After accreditation has been granted, the principle means by which ASCLD/LAB monitors compliance are an annual review report filed by the laboratory director and proficiency-testing reports submitted by approved test providers. This presentation is a discussion and review of the accreditation process.

Back to index


Problem Solving and Change in Forensic Science
L. A. Presley
Federal Bureau of Investigation
Washington, DC

It must be considered that there is nothing more difficult to carry out, nor more doubtful of success, nor more dangerous to handle, than to initiate a new order of things.


Motivations for Quality

The motivation for quality in forensic science stems from a sense of justice. If analytical results can help to include or exclude a suspect or add reliable information to an investigation, then forensic examinations may directly contribute to justice being served by the courts. The objective of the forensic practitioner is to obtain a reliable result relevant to a particular criminal case. Within the domain of quality results is the need for continuous improvement of the forensic examination processes, and this requires problem solving and changing to improved practices.

Problem Solving

Problem solving is not a recent invention in American culture, and it is an invention primarily of American philosophers. The pragmatism philosophy from the mid-1800s was a search for the elements of truth using a practical problem-solving approach. American philosophers such as Pierce, James, Schiller, and Dewey all made contributions to the establishment of the problem-solving characteristic of American culture.


Problem-Solving Evolution
Problem solving may involve the following hierarchical evolution:


Immediate reaction: inadequate resolution, finger pointing;

Teams assigned to attack big problems: no long-range solutions.


Corrective action established: problems generally resolved;

Problems identified early: all functions open to improvement.


Except in usual cases, problems are prevented.

Legal Influences in Forensic Science

The problem-solving driving force in the forensic sciences is primarily the law. Historically, one of the best known legal decisions affecting forensic science is the Frye Rule. Basically, the Frye Rule states that “… the thing from which the deduction is made must be sufficiently established to have gained general acceptance in the particular field in which it belongs.”

More recently, the Daubert Rule is becoming the standard for admissibility of scientific or technical testimony. The Daubert Rule attempts to answer the following questions:

  • Does the theory or technique involve testable hypotheses?
  • Has the theory or technique been subject to peer review and publication?
  • Are there known or potential error rates and are there standards controlling the technique’s operation? and
  • Is the method or technique generally accepted in the scientific community?

The Federal Rules of Evidence, which have parallel rules in states, also address forensic expert testimony. The Federal Rules of Evidence include the following relevant statements:

  • Rule 104: Questions of admissibility generally. Qualification of the person to be a witness, or admissibility of evidence. Relevance conditioned on fact.
  • Rule 403: Relevant evidence may be excluded if probative value is substantially outweighed by danger of unfair prejudice, confusion, misleading the jury, or needless presentation of cumulative evidence.
  • Rule 702: If scientific, technical, or other specialized knowledge will assist the trier of fact, a witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify.
  • Rule 703: The facts or data in a particular case upon which an expert bases an opinion may be those perceived by or made known to the expert at, or before, the hearing. If reasonably relied upon, the facts or data need not be admissible in evidence.

These legal elements help to create and define the objectives that are strived for in forensic analyses.

Forensic Science Quality Objectives

The forensic science quality objectives apply to two major areas of forensic examinations: methods’ validation and casework. The following lists the necessitating legal elements of forensic analysis:

  • Methods Validation
    • Sufficiently established
    • Generally accepted
    • Testable
    • Published
    • Established error rate
  • Casework Specific
    • Peer reviewed
    • Controlling standards used
    • Relevant
    • Competent/qualified
    • Unbiased, clear, clarifying, needed
    • Reasonably relied upon

These legal elements are relied upon by the judge in the admissibility of evidence and testimony in criminal case. The quality of the forensic analyses must meet or exceed these legal criteria.

Forensic Science Quantity Objectives

The quantity objectives of forensic analyses should work concurrently with the quality objectives of forensic analyses to produce high-quality results in reasonable time periods. Case productivity is usually measured by turn-around time and, to a lesser extent, by court testimonies. Ideally, quality and quantity should complement each other. Initially, quality will negatively affect quantity. However, over the long term, quality should enhance and support quantity objectives (see Figure 1).

Problem-Solving Tools

There are three generally accepted problem-solving and quality-improvement tools: audits, corrective actions, and preventive action.

Audits are planned, independent, and documented assessments to determine whether agreed upon requirements are being met.

Corrective actions are actions designed to thoroughly address a problematic issue. Corrective actions can be applied to immediate situations, the elimination of a situation, or the process to plan assistance to customers who have a specific kind of unsatisfactory service potential. Corrective action may be used in any of the following situations:

  • Detecting the lack of training to retrain and restart the process;
  • Using autopsies to determine with precision the symptoms exhibited by the product and process;
  • Comparing before and after products;
  • Establishing the relationship between the process variables and product results;
  • Reconstructing the chronology:
    • Events before and after; and
    • Time-related information (for example, waiting times).

Corrective action may also invoke the following remedies:

  • Reevaluating standards/criteria;
  • Instituting form changes;
  • Changing the quality system operations as necessary;
  • Allocating resources to correct problems;
  • Improving physical and professional environment;
  • Training and retraining as necessary;
  • Coaching and counseling as appropriate;
  • Using newsletters to inform employees;
  • Allocating workloads based on staff and resources; and
  • Terminating ineffective resource allocations.

Preventive action is a pro-active process used to identify improvement opportunities, rather than a reaction to the identification of problems or complaints. It may involve review of operational procedures, analysis of data including trend analysis, analysis of proficiency-testing results, and risk analysis.


We are all responsible for the ongoing improvement of the forensic science services we deliver. We need to employ the proper problem-solving and change tools to create the right systems and environment for high-quality forensic practices. Our objective is to ensure that forensic analyses can be reliably used by the criminal justice system and that justice is served.


Arter, D. R. Quality Audits for Improved Performance (2nd ed.). ASQC Quality Press, Milwaukee, Wisconsin, 1994.

Crosby, P. B. Quality Is Still Free. McGraw-Hill Book Company, New York, 1996.

ISO/IEC Guide 25-1990. General Requirements for the Competence of Testing and Calibration Laboratories.

Juran, J. M. and Gryna, F. M. Juran’s Quality Control Handbook (4th ed.). McGraw-Hill Book Company, New York, 1988.

Back to index


Basic Specialized and Continuing Education and the Implication for Quality Assurance Processes
A. M. Ross

National Institute of Forensic Science
Bundoora, Victoria, Australia

There is no doubt that initial education and ongoing training of personnel plays a critical role in the overall quality management program of an organization. There are a number of tools that can be used to identify training requirements. These include skills audits, training needs analyses, proficiency tests, and outcomes of the emerging scientific working groups.

There needs to be a balance in training between externally delivered and externally assessed programs and the more practically oriented in-house programs. Appropriate assessment is vital for the credibility of training outcomes.

Competency-based training is designed to provide the appropriate skills for an individual’s current working environment and activities.

Current technology such as interactive CD-ROMs and the Internet allows for tailoring of training programs and gives the purchaser a range of options to meet individual requirements.

Therefore, there can be complementarity between training and quality management demands.

Back to index


European Network of Forensic Science Institutes
J. Thompson
Forensic Science Service
Birmingham, United Kingdom

Europe and the European Union

Dramatic changes have occurred in Europe during the past 12 years. The Maastricht Treaty paved the way for greater police and judicial cooperation between member states of the European Union; the Schengen Convention heralded the removal of border controls and greater freedom of movement on mainland Europe; and, perhaps most important of all, the fall of the Berlin Wall and the collapse of Communism opened up Eastern Europe with new states forming from the old Soviet Union to the west.

With these changes, the European Union has experienced increased organized crime spreading from Eastern Europe. The greater freedom of movement has opened up new routes for criminals and criminal organizations trafficking in a variety of goods including drugs, firearms, plutonium, and people. Clearly, this has had consequences for the investigation of organized crime and serious cross-border crime.

On 1 October 1988, Europol was established as an European Union-wide organization responsible for facilitating cooperation between police forces of member states. The European Union also began to take a more active role in encouraging interagency cooperation and police and judicial cooperation between member states. The European Union saw its priority as the effective tackling of serious crime, drugs, and illegal immigration, and it placed particular emphasis on practical cooperation between the agencies supporting the police, customs, other law enforcement agencies, and the judiciary.

European Network of Forensic Science Institutes (ENFSI)

In the forensic science field, regular cooperation has existed at the technical level since the mid-1980s.

In Spring 1992, the Gerechtelijk Laboratory in the Netherlands launched the idea of organizing regular meetings for directors from the main public service/government forensic science laboratories in Western Europe. The following year a meeting was held in the Netherlands to discuss the formation of a European Network of Forensic Science Institutes, and between March 1993 and October 1995, six meetings were held. The topics discussed included accreditation of forensic science laboratories, quality management, forensic education, automation of crime laboratories, and international cooperation. ENFSI was formally founded in October 1995.

ENFSI has since developed into an organization with 39 members from 25 countries within Europe, including 13 of the 15 European Union member states:

Czech Republic
France (2)
Germany (5)
Italy (2)
Poland (2)
Russia (2)
Spain (2)
Switzerland (3)
United Kingdom (4)

The majority of the members are directors of institutes that are the major providers in their country of forensic science services in support of crime investigation by the police and other law enforcement agencies and the prosecution of offenders.

The aim of ENFSI is to promote cooperation between its members and their laboratory staff through discussion of managerial issues, the effective use of forensic science, scientific developments, and standards of practise. This involves participation in scientific exchange programs, joint research and development, and sharing of information and expertise on best practise, quality assurance matters, and training. It also requires cooperation with other international organizations.

The strategic direction of ENFSI is managed through its board and an annual meeting of its members. For the period 1997–2002, it identified four major priorities:

  • Strengthen and consolidate ENFSI as an organization through the work of the board, working groups, committees, and meetings,
  • Position ENFSI as a source of advice to international organizations such as the European Union and Interpol,
  • Expand its membership throughout Europe while maintaining its development and credibility, and
  • Establish a working relationship with other similar organizations.

Significant progress toward accomplishing these priorities has since been made. ENFSI has been adopted by the European Union Police Cooperation Working Group as its adviser on forensic science issues. ENFSI’s members are also looking forward to establishing a memorandum of understanding with Europol. Membership applications continue to flow in. Since May 1997, a number of successful summit meetings have been held with the American Society of Crime Laboratory Directors (ASCLD) and Senior Managers of Australia and New Zealand Forensic Science Laboratories representatives.

ENFSI Working Groups and Committees

However, ENFSI has been most keen to address the practical and technical aspects of forensic science from an international perspective and to raise the standards of performance of all its member laboratories. The main thrust of this work has been through the activities of its working groups and committees.

Some of these predate ENFSI under different organizational arrangements and some are new, but now all are under the same umbrella and cover most of the main areas of forensic science activity:

  • Computer Crime
  • Document Examination
  • DNA
  • Drugs
  • Drugs Benchmarking
  • Education and Training
  • Explosives
  • Fibers
  • Firearms
  • Fire and Physical or Gas Explosions
  • Forensic Imaging
  • Handwriting
  • Marks
  • Paint
  • Quality Assurance
  • Scenes of Crime
  • Speech and Audio Analysis
  • Traffic

European Academy of Forensic Science

The working groups are open to all ENFSI members active in their area of interest, but scientists and academics from within and outside Europe can also be invited to join as guests. Their terms of reference require them to focus on the exchange of information or expertise promoting quality assurance, joint research and development, provision of education and training within their specific area, and establishing international access to their data collections.

The DNA Working Group has probably been the most active of late. For example, it has provided advice to the European Union Police Cooperation Working Group on the exchange of information relating to DNA profiles, and this has led to funding being provided from the European Union and to the group almost exclusive focus on this issue. It has carried out collaborative studies on DNA profiling and has already reached agreement to standardize throughout Europe on seven STR loci for European DNA databasing, not for a European DNA Database, but for national databases that contain compatible and thus interchangeable DNA profiles. It has developed quality assurance guidelines for DNA profiling. The chairman of the DNA Working Group, together with a number of other working group members, has recently been conducting an audit of a number of other European laboratories to check the extent to which they can comply with these requirements and where they need more assistance to reach the necessary standard.

The ENFSI Drugs Working Group has also been approached by the European Union Police Cooperation Working Group for advice on the establishment of an intelligence database covering synthetic drugs such as LSD, amphetamines, and the other amphetamine-type ecstasy stimulants. A member of Europol now attends all the Drugs Working Group meetings.

These are the types of things all the working groups are aiming for, addressing how forensic science can transcend the international cultural, legal, and language difficulties that we have in Europe.

But we do not want to do this just in Europe, in isolation from the rest of the world community. In DNA there is already good contact with the United States. We have unashamedly built on the very good work done by TWGDAM in taking our work forward, and the Chairman of the ENFSI DNA Working Group is on the New York State DNA Board. The Chairman of the ENFSI Fibres Working Group is a member of SWGMAT, and the Chairman of SWGMAT participates in meetings of the ENFSI Fibres Working Group. The Chairman of the ENFSI Quality Assurance Working Group and a member of the ENFSI Drugs Working Group have been working closely with TWGDRUG, and some of the other working groups have also established connections with interested parties elsewhere in America, Australia, and Asia. We would like to see much more interchange of experiences and scholarship along similar lines and would welcome further contact between the corresponding groups.

The European Academy of Forensic Science is a rather different animal from the other working groups and is tasked primarily with organizing open scientific meetings for ENFSI that are aimed at improving the interface between practising forensic scientists, academics, and the legal process. They take place usually every three years, and the next meeting is in Cracow, in September 2000. We look forward to seeing as many of you there as possible to help build on the excellent foundation of cooperation and understanding we have now established.


Back to index