Joseph L. Peterson

Crime laboratory proficiency testing results, 1978-1991, II: Resolving questions of common origin.

A preceding article has examined the origins of crime laboratory proficiency testing and the performance of laboratories in the identification and classification of common types of physical evidence. Part II reviews laboratory proficiency in determining if two or more evidence samples shared a common source. Parts I and II together review the results of 175 separate tests issued to crime laboratories over the period 1978 to 1991. Laboratories perform best in determining the origin of finger and palm prints, metals, firearms (bullets and catridge cases), and footwear. Laboratories have moderate success in determining the source of bloodstains, questioned documents, toolmarks, and hair. A final category is of greater concern and includes those evidence categories where 10% or more of results disagree with manufacturers regarding the source of samples. This latter group includes paint, glass, fibers, and body fluid mixtures. The article concludes with a comparison of current findings with earlier LEAA study results, and a discussion of judicial and policy implications.

The application of signal detection theory to decision-making in forensic science.

Signal Detection Theory (SDT) has come to be used in a wide variety of fields where noise and imperfect signals present challenges to the task of separating hits and correct rejections from misses and false alarms. The application of SDT helps illuminate and improve the quality of decision-making in those fields in a number of ways. The present article is designed to make SDT more accessible to forensic scientists by: (a) explaining what SDT is and how it works, (b) explicating the potential usefulness of SDT to forensic science, (c) illustrating SDT analysis using forensic science data, and (d) suggesting ways to gain the benefits of SDT analyses in the course of carrying out existing programs of quality assessment and other research on forensic science examinations.

Forensic Science Ethics: Developing an Integrated System of Support and Enforcement

This article reviews rules and codes adopted by operating agencies and professional societies which regulate the professional conduct of forensic scientists. The purpose, origin, and content of these codes are examined, with particular emphasis on their ability to address the major ethics-related problems confronting the field. The recently adopted ethics and management guidelines of the American Society of Crime Laboratory Directors are discussed as a major new policy having the potential of ensuring that benchworkers, managers, supervisors, and parent agency executives all subscribe to a common and comprehensive set of ethical standards.

The feasibility of external blind DNA proficiency testing. I. Background and findings.

We describe the origins, purposes, and findings of a national study to determine whether a large-scale program of blind proficiency testing in U.S. DNA laboratories is feasible and/or practical. Proficiency testing in clinical laboratories is reviewed, particularly as mandated by the Clinical Laboratory Improvement Acts and its role in the regulation of those laboratories. Proficiency testing in forensic urine drug testing labs is also briefly reviewed. Studies involving comparisons between open and blind proficiency testing are discussed. The clinical laboratory proficiency testing and regulation landscape provides the background for the DNA Act of 1994, and the congressional mandate to investigate blind proficiency testing in forensic DNA laboratories. Four models of blind proficiency testing are defined and discussed, along with the advantages and disadvantages of each and estimates of the costs of a large-scale program. The purposes of proficiency testing in a quality-assurance context are likewise discussed and related to the models and the arguments generally proffered for and against blind vs. open proficiency testing.

Teaching Ethics in a Forensic Science Curriculum

Higher education programs in forensic science seldom devote attention to issues of professional ethics in their curricula. This paper describes the results of a pilot study inquiring into the attitudes of undergraduate students before and after exposure to forensic science ethical standards and problems. Recommendations are offered concerning those terms and concepts with which students should be familiar and the skills they need to acquire.

Characteristics of Forensic Science Faculty within Criminal Justice Higher Education Programs

In 1980, the Joint Commission on Criminology and Criminal Justice Education and Standards surveyed more than 3600 faculty members from approximately 560 graduate and undergraduate criminal justice and criminology programs in the country. This paper compares the responses of faculty who indicated expertise in the forensic sciences with those of the larger group of criminal justice faculty members. More than 40% of the 61 faculty who specialize in forensic science have backgrounds in law enforcement and are teaching at two-year institutions. Less than 10% of these faculty have crime laboratory work experience. Teaching is clearly the primary activity of these faculty, with a small percentage of their time devoted to research and writing. The forensic science faculty are also notable in that they customarily teach in an adjunct status and do not hold academic appointments that will lead to permanent status with a college or university.

Symposium: Ethical Conflicts in the Forensic Sciences Introduction

Throughout the history of the forensic sciences, its members have shown a particular concern for the attainment of high professional and ethical standards. Forensic scientists are expected to be honest with respect to their qualifications, examinations, and conclusions; they should be technically competent and only use methods of proven reliability; they should remain totally objective and nonpartisan with respect to their review of evidence and delivery of expert testimony; and they are expected to present understandable and balanced reports/testimony to legal decision makers. However, the reality is that forensic scientists function within an adversarial system of justice that places a high premium on winning cases. They, too, sometimes find themselves employed by units of the legal system that fail to provide the leadership and resources necessary to insure competent and balanced examinations of evidence.