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Crime
Reconstruction

by W. Jerry Chisum & Brent E. Turvey
© Elsevier, September 2006

   

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Crime Reconstruction
by W. Jerry Chisum & Brent E. Turvey
Hardcover, 608 pages
Published by Academic Press, an imprint of Elsevier, 2006
ISBN: 0123693756


PREFACE

A HOLISTIC APPROACH TO CRIME RECONSTRUCTION
by W. Jerry Chisum and Brent E. Turvey

Relating to or concerned with wholes or with complete systems rather than with the analysis of, treatment of, or dissection into parts. Emphasizing the organic or functional relation between parts and the whole. Holistic, Dictionary Definition

What is the nature of the whole, and what is my nature, and how this is related to that, and what kind of a part it is of what kind of a whole. —Marcus Aurelius Antoninus, 167 CE, Meditations, Book II

 

Holistic crime reconstruction is the development of actions and circumstances based on the system of evidence discovered and examined in relation to a particular crime. In this philosophy,  all elements of evidence that come to light in a given case are treated as interdependent; the significance of each piece, each action, and each event falls and rises on the backs of the others. More evidence gives rise to more meaning, and less evidence necessarily allows for the resolution of less meaning. The final reconstruction is a function of this system, of  how much evidence there is, and whether and how it interrelates and maintains its consistency.

A system of related evidence and any conclusions based thereon are like a mechanical engine or a biological organ, with few if any extraneous parts working judiciously, and in harmony, toward a desired end. If one of the parts fails, then the whole system suffers and may fail. With evidence and its interpretation it is precisely so. Interpretations must be compatible, working in concordance to support each other. Or at the very least not working against each other. Bloodstain pattern interpretations must not contradict the ballistic analysis, trace evidence must not contradict the conclusions of the arson investigator, DNA evidence must not contradict the conclusions of the fingerprint examiner, and so forth. A concordance of the evidence must be apparent. The reason for this is straightforward. Although it can be forgotten in a climate that seeks and rewards certain conclusions (namely the climate of the courts), all science, and even forensic science—especially forensic science—is grounded in skepticism. It necessarily follows that a finding out of harmony with any of the others in its system should call one or all into question.

 

Origins: The Forensic Generalist
The foundation for holistic crime reconstruction doctrine was introduced more than a century ago, with the 1894 publication of Handbuch fur Untersuchungsrichter als System der Kriminalistik (Criminal Investigation: A Practical Textbook for Magistrates, Police Officers and Lawyers) by the legendary Austrian jurist Dr. Johann (Hans) Baptist Gustav Gross. The goals of this manual were formative and ambitious: to establish principles of scientific investigation and to provide for the birth of the scientific investigator. The manual was a broad success with international appeal, achieving no less than five English editions (1906, 1924, 1934, 1949, and 1962). It also provided the basis for the practical work later undertaken by French scientist Dr. Edmund Locard when he established what is considered to be the world’s first police crime laboratory in Lyon, France, in 1910. Despite the passage of time and advances in technology, the philosophies of System der Kriminalistik remain a touchstone of forensic knowledge and wisdom to the present day.

The approach to crime reconstruction advocated by Dr. Gross, and subsequent students of his work, was to assign such duties to a scientific investigator—what would be referred to in more modern language as a forensic generalist. The scientific investigator was to be a professional schooled broadly in the subjects of crime, criminals, and the scientific methods of their identification, apprehension, and prosecution. Their role was to understand how the system of evidence and details of a case could be established, how they could be related, and how they could be interpreted. This holistic method, branded by dispassion and an adherence to science, would ideally free the scientific investigator from the constraints of politics, cronyism, and emotional bias.

The philosophy of Hans Gross was mirrored in many subsequent published works and aspired to in numerous crime labs throughout the United States.

 

The Forensic Generalist Fades
At present, the forensic generalist is all but a memory and until recently (Turvey, 1999; Inman & Rudin, 2000; Savino & Turvey, 2004) had not made an honest appearance in forensic science textbooks since DeForest, Gaensslen, and Lee (1983). More curiously, some forensic professionals become angered when generalists are described, let alone remembered. There is more than one reason for the disappearance of the generalist and related professional sensitivity. We focus on the three most apparent: overspecialization, diminished crime lab budgets, and the false paradigm of sides.

The Gross Facts
Forensic generalists and forensic specialists alike are a requirement for informed forensic case examination, laboratory testing, and crime reconstruction to occur. A forensic generalist is a particular kind of forensic scientist who is broadly educated and trained in a variety of forensic specialties. They are “big picture” people who can help reconstruct a crime from work performed with the assistance of other forensic scientists and then direct investigators to forensic specialists as needed. They are experts not in all areas, but in the specific area of evidence interpretation. According to DeForest et al. (1983, p. 17),

Because of the depth and complexity of criminalistics, the need for specialists is inescapable. There can be serious problems, however, with overspecialization. Persons who have a working knowledge of a broad range of criminalistics problems and techniques are also necessary. These people are called generalists. The value of generalists lies in their ability to look at all of the aspects of a complex case and decide what needs to be done, which specialists should be involved, and in which order to carry out the required examinations.

Specialization occurs when a forensic scientist has been trained in a specific forensic subspecialty, such as an area of criminalistics, forensic toxicology, forensic pathology, or forensic anthropology. Specialists are an important part of forensic science casework, with an important role to fill.  Traditionally, forensic specialists provide the bricks, and forensic generalists have traditionally provided the blueprints.

In the modern forensic system, the majority of forensic scientists have become so specialized in their analytical functions that they are no longer in possession of the gross facts in the cases they work. This is a source of both angst and embarrassment to some crime lab personnel, because they would prefer that their analyses be better informed. Still others would prefer to retain the appearance of overall forensic authority that knowing the full case facts allows. Nowadays, a piece of evidence is brought to a crime lab or examiner, it is examined using a specific method, test, or procedure as the requesting agency dictates, a report of findings is written, and the overall context may or may not be known or even sought. Without the gross facts of a case, and at least some knowledge of assembling them, crime reconstruction cannot occur. Not participating in this process, for lack of skill, time, or invitation, has become a sore point for some in the community of forensic science specialists.

Underfunded and Understaffed
In terms of money, government crime laboratory budgets nationwide rarely allow for the full suite of forensic specialties, with, for example, trace evidence units vanishing in the shadow of the forensic titan that DNA has become because of its acceptance by the courts. Money, after all, is allocated for those areas of forensic science that the court has embraced. Money is not allocated for areas of forensic science that the court shows disinterest. Also, money for research is often a luxury that cannot be afforded at all.

Furthermore, government labs have faced severe budget and personnel shortages in recent years. There are several interwoven reasons for this. First, the demand for lab services has increased with the growing national profile of forensic science thanks to the popular media. More law enforcement officers are coming to understand that forensic evidence can help their cases, more juries are expecting it at trial, and as a result government crime labs are being asked to do more examinations on more evidence. Second, practice standards in many regions have evolved to meet the needs of crime lab certification. Nationwide, many of the larger government crime labs and lab systems are suffering excruciating independent reviews and scrambling to meet the criteria set by the American Society of Crime Lab Directors Laboratory Accreditation Board (ASCLD/LAB) in order to claim this coveted credential in court. To meet ASCLD/LAB criteria, more of the diminishing lab budget must be spent on quality control, adequate workspace, and adequate evidence tracking and storage. Additionally, each person must complete a proficiency test on each type of evidence he analyzes each year. This slows the amount of time forensic scientists have to work on case material and can, in extreme cases in which there are staff shortages, put the examination of evidence on hold for periods of time. The accreditation process is not easy, and it even requires some labs to simply start over and build entirely new multimillion-dollar facilities. This to say nothing of the requirement to hire more adequately qualified personnel, bringing front and center the problem of too few qualified candidates available with less money to pay them. Additionally, new forensic analytical techniques are not encouraged because they must be “proven methods”—refinements of methods are not allowed. This works against the intention of the scientific method and stamps out the spark of creativity because many of the past advances in crime lab analysis were the result of “experimentation” with actual case materials and trying something new. Third, the public funding of state crime labs constantly suffers at the hands of wary voters who tend to lack enthusiasm for raising taxes to help fund education, let alone forensic science.

With all of these factors at work, many government crime labs do not have the time, the resources, or the personnel to perform their regular analytical casework. As a consequence, backlogs have mounted in almost all areas of forensic analysis. In this environment, the extra time and commitment required for crime reconstruction is an added expense that becomes difficult for administrators to justify.

The Paradigm of Sides
The paradigm of sides challenges forensic scientists on two fronts, presenting a false choice in which they are invited to abandon their chosen profession for advocacy. First, there is the obvious division between the prosecution and the defense. More than a few forensic scientists work in an environment that rewards them for thinking and behaving as though there is a morally right side of the courtroom and a morally wrong side of the courtroom. By choosing fidelity to one side of the courtroom over another, the forensic scientist not only loses that which defines science, namely objectivity, but the forensic scientist also presumes a role in court not meant for any expert or witness - that of the trier of fact. It is not the place of the forensic scientist to decide who is worthy of a defense, who is legally or actually guilty, or how they should be punished. These are moral and legal conclusions, which brings us to the second part of the paradigm of sides: the division between scientific fact and legal truth. The forensic scientist is an educator to the court. It is the role of the forensic scientist to establish scientific fact and explain what it means to an investigator, attorney, judge, or jury in the context of a given case. Moreover, the scientific facts should be the same no matter which side the forensic scientist is working for. It is the role of the judge and jury, not the forensic scientist, to form legal conclusions about who is guilty of what, and what the penalty should be based on the totality of evidence.

Although often confused, scientific fact and legal truth are not the same thing. Scientific fact is established through careful examination using the scientific method. Legal truth is determined by the trier of fact, based on available and admissible evidence, as well as their understanding of the law. This is made abundantly clear in cases of wrongful conviction, in which a person may be found legally guilty of a crime without having actually committed it. Juries do not, consequently, determine the ultimate facts of a case, only the legal facts. This distinction becomes important when one considers the roles played in our justice system by directed verdicts, appellate courts, supreme courts, gubernatorial pardons, and DNA exonerations, all of which have the power to influence or overturn a juries estimation of the facts and its final verdict. Subsequently, the abilities of a forensic scientist are not measured in arrests, convictions, or even acquittals, as will be made evident throughout this work. Forensic science, although a servant to court, must serve itself first in order to have any intrinsic value. When science chooses a side other than itself in any conflict or dispute, it is no longer science but advocacy.

The majority of forensic scientists have no trouble understanding the gravity involved in navigating the paradigm of sides on this level and would rather resign from a case or an agency than sacrifice their objectivity and integrity. The true forensic scientist knows that his first onus is to his profession, and that if there is no science, there can be no forensic science.

This community understanding is all well and good until it is remembered that a fair number of forensic scientists work in government crime labs that are housed within, or directly supervised by, police agencies or district attorney’s offices. In terms of the actual reconstruction of crime, police and prosecutors are faced with the reality that the scientists they employ may not always agree with their theories regarding a case. In fact, in some instances, the evidentiary findings of the crime lab may hamper or even disprove an important point upon which a police or prosecution theory is built. For some government agencies, this internal evidence-based self-correction is a welcome adjustment to the course of a criminal investigation and any future prosecution. However, history has shown that this is not always so. Not all government crime labs enjoy an open or healthy relationship with their law enforcement and prosecutorial supervisors. Also, a significant number of government agencies remain hesitant to put their scientists in a position in which they can reconstruct the crime in its entirety and then be called by the defense as witnesses against them.

The paradigm of sides presents the forensic scientist with a false choice between prosecution or defense; between scientific fact or legal truth. Pressure to choose can be brought to bear in many ways—personal, professional, and financial. Furthermore, the pressure on a forensic scientist in such environments, to be part of the “team” and help “get the bad guys,” can be seductive and overwhelming to the point of assimilation. As discussed later in this book, the rewards for assimilation are great, and the consequences for failing to assimilate can be equally great.

Overspecialization, diminishing budgets, and the paradigm of sides—in such ways the practice and implementation of crime reconstruction has, with some exceptions, faded from many crime labs and been moved into the hands of others.

The authors view this with neither frown nor favor,but rather agree to recognize that it is so; all manner of reconstruction opinions find their way into court from a variety of sources. However, in many instances, it has become clear that scientific reconstructions are being subverted and even intentionally excluded.  Consequently, with its departure from the crime lab, the practice of crime reconstruction is in no small danger of losing its footing on the ascending ladder that is the employment of scientific principles to evidence interpretation. Under no circumstance should this situation be acceptable. As such, the need for the development of this textbook becomes apparent.

Modern Crime Reconstruction
Modern forensic science and crime reconstruction is slowly becoming the work of police technicians trained inexpensively through short courses and lectures, as opposed to formally educated forensic scientists shepherded by mentors of quality experience. The difference between the two is significant. Forensic scientists do not just test or examine evidence and then record the results; they are meant to explore, understand, and explain its significance. Thornton (1997, p. 3) provides a succinct and accurate description:

The single feature that distinguishes forensic scientists from any other scientist is the certain expectation that they will appear in court and testify to their findings and offer an opinion as to the significance of those findings. The forensic scientist will testify not only to what things are, but to what things mean.

This is the very heart of crime reconstruction—not just what, where, and when, but also how and why.

The reconstruction of a crime from physical evidence is the culmination of a long and methodical process. It is the last step in the analytical journey each piece of physical evidence takes from the moment it is recognized at a crime scene. Those steps occur in roughly the same order for each item of evidence:

1. Recognition

2. Preservation

3. Documentation

4. Collection

5. Transportation

6. Identification/classification

7. Comparison

8. Individuation

9. Interpretation/reconstruction

Traditionally, the specific duties are broken down as follows:

Detective/investigator/forensic technician

1. Recognition

2. Preservation

Forensic technician (aka crime scene technician)

3. Documentation

4. Collection

5. Transportation

Forensic scientist/criminalist

6. Identification/classification

7. Comparison

8. Individuation

9. Interpretation/reconstruction

The problem is that these forensic titles and roles are often mixed, misunderstood, or outright confused, sometimes over many generations of professionals in a given system. As a result, forensic job titles abound, with more than one to describe the same set of duties—crime scene investigator, crime scene technician, forensic investigator, evidence technician, forensic technician, laboratory technician, laboratory specialist, forensic specialist, forensic analyst, forensic scientist, criminalist, etc. What is important to remember about titles is that they are administrative and not necessarily suggestive of a particular background, education, training, or expertise. It is the work that defines the professional. It is education, training, experience, and the quality of work products that define expertise.

For the purposes of this text, it is important to become disentangled from this avalanche of jumbled titles and return to classic definitions for the purpose of clarity.

A technician is one who is trained in specific procedures, learned by routine or repetition. A forensic technician is trained in the specific procedures related to collecting and even testing evidence found at crime scenes. This is without any need for employing or even understanding the scientific method and the principles of forensic science. This describes the police technicians documenting crime scenes and collecting evidence, and more than a few of the forensic personnel working in government crime labs.

A scientist is someone who possesses an academic and clinical understanding of the scientific method and the analytical dexterity to construct experiments that will generate the empirical reality that science mandates. A forensic scientist is one who is educated and trained to examine and determine the meaning of physical evidence in accordance with the established principles of forensic science, with the expectation of presenting her findings in court. This describes fewer and fewer of those practicing forensic science in government crime labs .

As the authors have experienced on countless cases, it is technicians, investigators, and ultimately attorneys who are actually providing a majority of crime reconstructions in court, often with little understanding of forensic science or the scientific method, to say nothing of the natural limits of physical evidence. Crime lab personnel are performing any necessary laboratory analysis, but police and prosecutors are taking the final step to explain events and their relationships in court. This has the net effect of elevating the lay testimony of investigators and forensic technicians to that of the forensic scientist and of reducing the expert findings of the forensic scientist to the level of the technician.

Without the proper scientific foundation, technicians and detectives performing crime reconstructions may do so without a sense of what good science is and what constitutes the difference between assumptions, opinions, theories, and facts. To say nothing of failing to understand the actual science beneath the methods or instruments they employ in the search for evidence, a reality that often causes their explanations of false positions and false negatives to be works of useful fiction. In a related fashion, they also tend to fail with regard to grasping the necessity for testing their theories, and for continually attempting to falsify them against the revelations of experimentation and newly developed information. A scientist knows that confirmation of one’s theories is easy to find, especially if that is all one seeks. Good science is not about trying to prove one’s theories but, rather, working tirelessly to disprove them through falsification (Popper, 1963).

Holistic Crime Reconstruction
This textbook is aptly titled Crime Reconstruction. It is not a manual intended to explain the technical mechanics of searching or processing crime scenes or to delineate the rote procedures related to instrumental laboratory analysis. There are plenty of texts available that adequately cover these very important considerations, without which reconstruction would be impossible. As already discussed, holistic crime reconstruction is the development of actions and circumstances based on the system of evidence discovered and examined in relation to a particular crime. It is best conceived as the function of a forensic generalist. Our purpose is to educate students and prepare generalist practitioners of the forensic sciences as to the manner in which interpretations regarding evidence may be legitimately achieved and expressed.

As we have suggested, not everyone agrees with the forensic generalist model. One of the philosophical arguments against the generalist is that “one cannot be an expert in everything.” As already stated, we do not propose that to perform crime reconstruction one needs to be an expert in all forensic disciplines. We propose that forensic reconstructionists must become an expert in only one: the interpretation of the evidence in context. If students wish to pursue further knowledge about examination and analysis in a particular discipline, then there are several excellent publications that are available for that purpose. However, there has never been a textbook devoted only to the interpretation of evidence in context—the proofs, the perils, and the prevarications. Consequently, those studying and performing crime reconstruction have perhaps lacked some advanced measure of informed guidance on the subject. It is our collective goal to assist with filling that void.

Crime reconstruction, to be accurate, must be based on a close scientific examination of the physical evidence and the surrounding environment. These examinations must be the result of applying the scientific method. Interpretations of the meaning of subsequent results must be clearly derived by logic and critical thinking. We will try to explain these concepts so that students can understand that crime reconstruction is not just mere observation and speculation. We will also give students several ways to approach the problem of how reconstruction may be competently performed. Throughout this work we have included reconstruction techniques, interpretation guidelines, and even practice standards.

Also, students will come to appreciate that the crime scene is a dynamic location; it does not remain virginal or static, as a “frozen moment of time,” but rather it is constantly subject to change. The greater the time interval between the crime, the documentation, and examination of the scene, the greater the changes may be. These changes we have referred to as evidence dynamics. To be ignorant of the problems inherent in the interpretation of the evidence due to evidence dynamics can result in serious misinterpretation errors.

Different areas of physical evidence offer opportunities for reconstruction. Bloodstains, firearms, arson, and trace evidence all contribute to the whole. We have included chapters on each of these types of evidence by some of the leading experts in these fields.

Finally, there are chapters on ethics and expert testimony so that students may understand how to comport themselves professionally and what truly waits for them in the courtroom. The perspectives of the forensic scientist and the attorney are provided. As readers will come to appreciate, these considerations are far from trivial.

It is important for students of forensic science to learn that no one discipline can truly stand alone in a reconstruction. Each form of evidence must be in agreement with the other forms that are present. Each part must be meticulously established and then considered not just on its own but also in its place as part of the greater whole. What is it, how does it fit, and what does it mean in context—these are the questions asked by a reconstructionist.

Given this holistic approach, the authors have come to view reconstruction as the work of one who is sufficiently educated, trained, and experienced to understand the total body of forensic evidence and analysis in a case. That is, again, the forensic generalist. The generalist–reconstructionist, it must be understood, need not know how to perform all of the forensic examinations that were conducted. They need not have the ability to operate a camera to view a photograph; they need not have the ability to extract DNA and amplify it to comprehend a DNA analyst’s report; they need not have the ability to perform an autopsy to understand the cause and manner of death, and appreciate the trajectory of the projectiles that passed through the body. Rather, they must be able to understand what the results of forensic examinations are, how they were reached, what they mean, and how they may be integrated to create of picture of events. Integration of findings is key because crime is best reconstructed when forged by a collaboration of the forensic evidence, and not a reliance on one single examination or discipline. To rely on one piece of evidence, or one theory, without placing it in context is not only potentially misleading but also a disservice to the justice system that the forensic scientist ultimately serves. It is our collective hope that this text will be worthy of that service and will assist the next generation of forensic generalists with the difficult tasks that are before them.

 

REFERENCES

DeForest, P., Gaennslen, R., and Lee, H. (1983). Forensic science: An introduction to criminalistics. New York: McGraw-Hill.

Gross, H. (1906). Criminal investigation. Madras, India: Ramasawmy Chetty.

Gross, H. (1924). Criminal investigation. London: Sweet & Maxwell.

Inman, K., and Rudin, N. (2000). Principles and practice of criminalistics: The profession of forensic science. Boca Raton, FL: CRC Press.

Popper, K. (1963). Conjectures and refutations. London: Routledge &Keagan Paul.

Thornton, J. (1997). The general assumptions and rationale of forensic identification. In D. L. Faigman, D. H. Kaye, M. J. Saks, and J. Sanders (Eds.), Modern scientific evidence: The law and science of expert testimony (Vol. 2). St. Paul, MN: West.

Savino, J., and Turvey, B. (2004). Rape investigation handbook. Boston: Elsevier.

Turvey, B. (1999) Criminal Profiling: An Introduction to Behavioral Evidence Analysis, London: Elsevier Science.


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Last update: 06/13/2006