Forensic Anthropology

Transcription

1 Forensic Anthropology Cutting Edge Science William R. Belcher, Ph.D., D-ABFA (No. 66)

2 CES: Forensic Anthropology ISBN: Published by Quantum Scientific Publishing a division of Sentient Enterprises, Inc. Pittsburgh, PA. Copyright 2008 by Sentient Enterprises, Inc. All rights reserved. Permission in writing must be obtained from the publisher before any part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or by any information storage or retrieval system. All trademarks, service marks, registered trademarks, and registered service marks are the property of their respective owners and are used herein for identification purposes only. Printed in the United States of America Quantum Scienti c Publishing Cover design by Andrew Miller and Laura Johnson

3 Lincoln Interactive is dedicated to helping schools meet the demands of 21st century learners. Designing, developing, and delivering high-quality curriculum that makes innovative and e ective educational experiences available anywhere, Lincoln Interactive is o ering schools and communities cu ing-edge strategies for creating and sustaining academic excellence. The Lincoln curriculum is one of the rst comprehensive elementary through high school series developed exclusively for online learning. This innovative, challenging, standards - based and peer - reviewed coursework is available to any school seeking to enhance and expand its educational services. Lincoln Interactive o ers a full slate of both basic and advanced courses. Lincoln Interactive is truly a 21st Century curriculum choice that provides engaging student centered educational experiences. Forma ed to a unique and consistent design model, Lincoln Interactive courses o er exibility in scheduling, a variety of course content, and regular feedback from highly trained, certi ed teachers. Each course provides experiences in varying learning styles. Multiple levels of interaction are available to students allowing them to receive as li le assistance as they want or as much help as they need to succeed. Pod casts, streaming video, illustrations, songs, and gaming simulations create truly engaging and interactive lessons. The Lincoln Interactive Curriculum is comprised of student friendly courses with a wide range of opportunities for academic mastery, investigation, and interaction.

4

5 UNIT ONE SECTION 01: Introduction to Forensic Sciences 2 SECTION 02: Introduction to Forensic Anthropology and Odontology 14 SECTION 03: Forensic Odontology or Forensic Dentistry 20 SECTION 04: Protecting the Evidence through Forensic Archaeology 28 SECTION 05: Human Osteology 35 SECTION 06: Preliminary Assessment of Evidence, or What is this stuff? 48 SECTION 07: Forensic Signifi cance and Minimum Number of Individuals 54 SECTION 08: Determining the Biological Sex 60 SECTION 09: How old was this person? Estimating Chronological Age of the Deceased 68 SECTION 10: Stature, or How tall was this person? 75 UNIT TWO SECTION 01: Determining Ethnic or Racial Affi liation 84 SECTION 02: Trauma 92 SECTION 03: Forensic Odontology or Forensic Dentistry 99 SECTION 04: The Identifi cation Process: Creating a Biological Profi le 108 SECTION 05: Forensic Anthropology Laboratories: Civilian 117 SECTION 06: Forensic Anthropology Laboratories: Military 121 SECTION 07: Military Case Studies: August A Mass Grave in the Pacifi c 128 SECTION 08: A Country in Confl ict: Capacity Building in Forensic Archaeology in the Republic of Colombia 135 SECTION 09: Assisting in Identifi cation and Investigation in Paradise 141 SECTION 10: The Hollywood Factor and Reality 147 APPENDICES APPENDIX A: Answer Key CLIV APPENDIX B: Glossary CLXXI APPENDIX C: Human Bones CLXXXVIII Table of Contents

6

7 Forensic Anthropology Cutting Edge Science

8

9 unit Introduction to Forensic Sciences 1.2 Introduction to Forensic Anthropology and Odontology 1.3 Forensic Odontology or Forensic Dentistry 1.4 Protecting the Evidence through Forensic Archaeology 1.5 Human Osteology 1.6 Preliminary Assessment of Evidence, or What is this stuff? 1.7 Forensic Signifi cance and Minimum Number of Individuals 1.8 Determining the Biological Sex 1.9 How old was this person? Estimating Chronological Age of the Deceased 1.10 Stature, or How tall was this person?

10 1.1 Introduction to Forensic Sciences 2 Section One: Introduction to Forensic Sciences Defi ne forensics Describe the three different types of evidence of evidence Describe several different areas of specialty in forensic science 1 Explain the general process involved in the physical analysis Introduction The goal of this section is to provide an outline of the broader topics of the forensic and investigative sciences as used in crime scene investigation and analytical sciences. This is an exciting field that is only a small part of the overall field of crime scene and forensic investigation. Many of the forensic sciences work hand-in-hand to help solve crimes or even determine if a crime has been committed. What is Forensics? Forensics in general is a form of argumentative discourse. This is why your high school debate team is often called a forensic team. How does this fit with criminal investigation? Well, it refers to the argumentative aspect of the legal system and refers to discussions that are suitable for discussion in a judicial format. Within the Forensics Module, we will use forensics in terms of this latter definition; that has to do with the scientific and medical methods used for legal questions. Forensic science refers to the use of a variety of investigation and scientific procedures used to assist the law enforcement and legal community or, as is often described the medico-legal community. Forensic investigation uses a wide variety of techniques ranging from visual observation and recording these ideas into a notebook to the most sophisticated form of DNA analysis. Forensic analysis, particularly in a laboratory setting, has the primary goals of examining, identifying, and comparing potential evidentiary items using a wide scope of scientific techniques and procedures. Through this analysis, an attempt is made to link suspect, victim, and crime scene through this material and biological evidence.

11 3 Introduction to Forensic Sciences 1.1 How does the term forensic differ in its use in a legal setting and the way it may be used in your school? CONCEPT CHECK ONE Evidence What is evidence? Well, as defined here, it includes physical or biological evidence. Physical evidence is defined as something that exists in a physical sense that is used in a court of law or criminal investigation that will be used in an argument to determine the matter of truth. Biological evidence is any item of evidence that originate from the biological world. Another form of evidence is referred to as trace evidence. Trace evidence includes those forms of evidence that can be extremely small, such as fibers or hair. Evidence also includes the relationships of different aspects of evidence to each other as well as the physical setting in which they are found. Crime Scene Investigation The entire forensic process begins with a crime scene or alleged crime scene. It is the responsibility of the crime scene investigators to oversee the entire process of documentation of the crime scene as well as the collection of the evidence. While many smaller jurisdictions in the United States have general crime scene investigators as an additional duty, larger metropolitan districts have entire teams, with each member specialized in specific forms of evidence collection and documentation. Crime scene investigation often begins with interviewing witnesses. This may be especially important to reconstructing events that occurred at the scene and is usually conducted by specially trained individuals.

12 1.1 Introduction to Forensic Sciences 4 What are the different types of evidence? CONCEPT CHECK TWO Physical Analysis of Evidence There are many types of forensic analyses that can take place in the field and in laboratories. The discussion of different types of analyses below is not meant to be complete or exhaustive, but really include topics you all may be familiar with because of television dramas or other readings. Any type of scientific analysis that can be used in a legal setting can be a form of forensic science. While extremely important, some of the more obscure (that is, not seen on television dramas) would be forensic geology and forensic engineering. For example, on August 1, 2007, the I-35W Bridge in Minneapolis, Minnesota collapsed during rush hour and, eventually, it was known that 13 people were killed, over 100 were injured, and much personal property was destroyed. The analysis of how that structure failed can be considered forensic engineering. Usually, evidence that is collected during an investigation is brought back to the laboratory. Care is taken to avoid possible contamination, particularly of samples like DNA (see below), but also that the chain of custody or chain of evidence is not broken. A chain of custody documents all individuals that have had access to evidence from the time of its collection to its possible presentation to a jury or other legal body in a court of law. Most of the evidence that is analyzed in a laboratory setting is called trace evidence. We often say that the devil is in the details. That means that through very detailed analyses of small pieces of evidence, we may be able to accomplish the tasks related to linking evidence to a victim, a perpetrator, and the scene. Any analyst must always consider the context of the evidence; however, most scientists are not concerned with the outcome of the legal action and are focused more on the analysis. This allows the analyst to remain blind in their approach to the analysis. Often blind samples are given in laboratories for a variety of reasons. This process maintains the objectivity of the analyst and it also may serve as a check to the analytical procedures. One important rule in dealing with trace evidence is called the exchange or transfer principle. This idea states that when two objects or substances come in contact with each other, portions of the other object or substance are transferred to the other. Thus, through detailed analysis we can identify these materials and then link them.

13 5 Introduction to Forensic Sciences 1.1 Specialty Areas in Forensic Science Toxicology is the analysis of foreign substances that are found in biological samples. It can include the use of chemical analyses (including analytical chemistry and clinical chemistry) and pharmacology. These analyses are used to aid medico-legal investigations into death, poisoning, or drug use. With the rise of illegal drug use, and their related deaths, in the United States, this accounts for most of the work in forensic or crime laboratories. Samples are usually related to possible drug samples at a scene as well as body fluids or biological tissue samples. Fibers are another important form of trace evidence. Fibers can originate from various sources either at the scene or on a person. The primary goal is to link a victim or alleged perpetrator to a scene through fibers found on or in areas associated with either person or scene. Through the use of a comparison microscope (or stereomicroscope), it is possible to compare physical attributes of samples found at various scenes and control samples taken from a variety of substances. This allows the analyst to determine the type of fiber and its possible origin. Also, through various comparisons, it may be possible to link fibers to a specific, individual source. For example, the fibers that compose duct tape may be examined. Specific fiber and tear patterns may be specifically matched between a piece found at a scene and the roll from which it was torn. This would allow a connection to be made between the scene and the roll of tape and, by extension, the owner of that roll of tape. Fingerprint identification has a long history in the use of forensic sciences. Some individual place the first use of fingerprinting as a form of identification back to 14th century Persia! Although much later, in the late 1800s, the use of fingerprints as a form of identification was presented to English police divisions and eventually adopted as a form of identification. Fingerprinting is based on the patterns seen in friction ridges in the skin. While generally referred

14 1.1 Introduction to Forensic Sciences 6 to as fingerprinting, these ridges occur on finger pads, toe pads, and over most surfaces of the palms and soles of the hands and feet. These are thought to be specific to individuals, but this has been questioned lately in U.S. courts as background statistical research on the uniqueness of friction ridges has not been demonstrated. Additionally, the validity of analyses has not been established in a scientifically reliable sense in a legal sense. Fingerprints can occur in three general types: latent prints which are left on a surface at a scene by chance or random act; patent prints are left at a scene through the transfer of the print by a foreign ma- Give some examples of trace evidence and the ways in which they are analyzed. CONCEPT CHECK THREE terial (such as blood) on the friction ridge; and, plastic prints which occur when a friction ridge is preserved in a plastic material such as clay or sediment. DNA fingerprinting. So-called DNA fingerprinting has all but superseded standard friction ridge work for identification of individuals. If any form of body fluid or biological tissue was left at a site, it may be possible to identify an individual, whether it is a victim or a person that was at the scene of the crime. DNA evidence is now used routinely to link individuals to a scene. DNA is a complex molecule found in two sources of all living cells. Most human cells are of complex type of eukaryotic cell that consists of various organelles and structures cytoplasm within a cellular wall. The most important of these structures, for our purposes are the cell nucleus and the mitochondria. Within the cell, the DNA that controls individual characteristics and has components contributed from both parents occurs in the nucleus. This is usually re-

15 7 Introduction to Forensic Sciences 1.1 ferred to as nucleic or genomic DNA. The DNA found in the nucleus is formed through fertilization when the complete DNA structure is brought together. The other major form of DNA found in cells occurs in the organelles known as the mitochondria, found in the cytoplasm outside of the nucleus. Mitochondria are considered the DNA is a complex, nucleic acid that contains genetic material or information that is used in the development growth, and maintenance of all living things. The DNA molecule model looks like a twisted ladder the double helix model. Structurally, DNA is composed of chains of nucleotides with a spine formed of sugars and phosphates. These sugars and phosphates form the rungs of the ladder. One of four complementary bases is attached to each sugar, thus, creating the rungs of the ladder. These bases encode the information that is necessary for life to exist and replicate. Through the process of mitosis, simple cell division occurs that allows the cells to replace those that are needed or lost during growth and injury. Through the process of meiosis, sex cells or gametes are produced that are various combinations of half of the genetic complement needed for life. During fertilization, these sex cells are combined to produce the complete complement. Due to the amount of variation that can occur during meiosis and during fertilization, the amount of diversity for each human is staggering. From the development and fertilization of gametes, it is possible to have a possible 70 trillion different combinations. Thus, each individual is considered unique. ENRICHMENT SECTION powerhouse of the cell and convert sugars and carbohydrates to energy that are necessary for the survival of the cell. The mitochondria contain short strands of DNA that are not involved in the reproductive process. In fact, mitochondrial DNA (mtdna) only comes from the maternal line or from the mother. Based on this uniqueness, biological samples, including hard and soft tissues and bodily fluids, contain unique genetic codes that can be

16 1.1 Introduction to Forensic Sciences 8 traced back to individuals with a high level of certainty. Bodily fluids such as blood and semen are the premier samples found at various times of crime scenes. Through DNA analysis or DNA fingerprinting, it is possible to compare samples found at a crime scene with an individual and determine a likely match. Because of the small amounts of genetic material, the possibility of contamination by inadvertent contact by the investigators or analysts is great. Much effort has been expended to control the contamination as well as the physical custody of these samples. Many samples have been contaminated or not allowed to be used as evidence due to the lack of control (chain of custody) of the samples from the scene to the laboratory. Identification of unknown human remains uses the same type of DNA fingerprinting. However, skeletonized remains contain little nucleic DNA or may be difficult to sample due to size or condition. Nevertheless, a less specific type of DNA, mtdna can be extracted from boney tissues. This is less specific because it does not represent an individual. Mitochondria are only inherited from the mother and the source of mitochondria occurs in the egg only. Because mtdna is inherited from the mother only, the sequences can be shared between siblings. So if we need to obtain a family blood reference sample, we can go to a victim s siblings or mother. If the victim is a female, we can obtain samples from her children (if she had any); however, we cannot obtain this type of sample from Discuss the differences between genomic DNA and mitochondrial DNA and where they might be used in forensic analyses. CONCEPT CHECK FOUR a man s children as their mtdna would originate from the mother and would not match his sequences. Therefore, we must obtain a sample from a sister s children. This type of analysis often requires the use of a genealogist to assist in the tracking down suitable relatives for an appropriate blood sample. Of course, these genealogists are called forensic genealogists!

17 9 Introduction to Forensic Sciences 1.1 Tool marks include unique aspects of tools that leave trace evidence at a scene. These tools may be used to create a clandestine burial, create blunt force or sharp force trauma on a body, or create any sort of mark at a scene. These marks can be general marks that identify a type of instrument (such as a type of shovel or pick) or they can exhibit individuating or specific marks that help identify an individual item (sometimes to a specific manufacturer, other times to a individual tool). Through the life of a tool, it can be reshaped or damaged through use. These activities usually leave a very specific signature on the tool that can be transferred to a variety of surfaces or media (including human biological tissue). Through specific macroscopic and microscopic analysis, it may be possible to match marks to the tools or at least get a general idea of the type of tool used at a scene. Ballistics is the science that deals with the physical characteristics of projectiles (including, but not limited to motion, behavior, and effects). A major use of ballistics in forensic sciences is to reconstruct projectile patterns as well as the comparison of projectiles found at a scene with a suspected weapon or system of discharge. Primarily this is done through the use of a comparison microscope where the different patterns seen on an evidentiary projectile are compared to one shot from a suspected weapon. These marks are the result of microscopic wear that occur during the life of a weapon. These marks are transferred to a lead projectile as it leaves the weapon. We discussed forensic sciences in a very broad manner in this section. Forensics is a form of argumentative discourse. In the forensic sciences, this means that the work done by experts in each area must be usable in a judicial setting, such as a court of law, for arguing the truth of the case being judged. Because the forensics analyses are being used to determine the truth of a situation, the forensic scientists must follow precise and documentable procedures in performing all of their analyses. Evi-

18 1.1 Introduction to Forensic Sciences 10 dence must be gathered, protected and documented through the chain of custody to ensure that true findings are presented to the court. There are many different forms of forensic science, including ballistics, fingerprinting, tool marks, DNA, toxicology and a number of other fields of expertise, that contribute to the overall picture developed of a case as it is analyzed.

19 11 Introduction to Forensic Sciences 1.1 VOCABULARY ACCIDENTAL Refers to deaths that are related to various causes that cannot be related directly or indirectly to specific individuals. BALLISTICS The science that deals with the physical characteristics of projectiles (including, but not limited to motion, behavior, and effects). BIOLOGICAL EVIDENCE Any item of evidence that originate from the biological world. BLIND SAMPLES Samples of evidence submitted for examination that are not identified in such a way that the analyst knows where they came from. This minimizes the introduction of bias into the analysis. CHAIN OF CUSTODY Documents all individuals that have had access to evidence from the time of its collection to its possible presentation to a jury or other legal body in a court of law. DNA Deoxyribonucleic Acid, a complex, nucleic acid that contains genetic material or information that is used in the development growth, and maintenance of all living things. DNA FINGERPRINTING Using any form of body fluid or biological tissue was left at a site to identify the individuals who were at the site by analyzing their DNA. DNA evidence is now used routinely to link individuals to a scene. EVIDENCE Something that exists in a physical sense that is used in a court of law or criminal investigation that will be used in an argument to determine the matter of truth. EUKARYOTIC An organism that has internal membranes and a cytoskeleton, including a membrane-bound structure called the nucleus. FIBER Another important form of trace evidence. Fibers can originate from various sources either at the scene or on a person.

20 1.1 Introduction to Forensic Sciences 12 VOCABULARY FINGERPRINTING Based on the patterns seen in friction ridges in the skin on the hands and used to identify individuals. FORENSIC ANALYSIS Has the primary goals of examining, identifying, and comparing evidentiary items using a wide scope of scientific techniques and procedures. FORENSIC INVESTIGATION Uses a wide variety of techniques ranging from visual observation and recording these ideas into a notebook to the most sophisticated form of DNA analysis. FORENSICS The use of a variety of investigation and scientific procedures used to assist the legal community. HOMICIDE Refers to a victim s death related to the direct and deliberate actions of others. LATENT PRINTS Are left on a surface at a scene by chance or random act. MEIOSIS Process of producing sex cells, or gametes, which are various combinations of half of the genetic complement needed for life. MITOCHONDRIAL DNA (MTDNA) Is found in the mitochondria and only comes from the maternal line or from the mother. MITOSIS Simple cell division occurs that allows the cells to replace those that are needed or lost during growth and injury. NATURAL DEATH Natural refers to conditions that are naturally occurring and are usually related to age or disease. NUCLEIC (GENOMIC) DNA The DNA that controls individual characteristics and has components contributed from both parents occurs in the nucleus.

21 13 Introduction to Forensic Sciences 1.1 VOCABULARY PATENT PRINTS Are left at a scene through the transfer of the print by a foreign material (such as blood) on the friction ridge. PLASTIC PRINTS Occur when a friction ridge is preserved in a plastic material such as clay or sediment. SUICIDE Refers to those deaths that are related to a victim causing their own death through either direct or indirect means. TOOL MARKS Include unique aspects of tools that leave trace evidence at a scene. TOXICOLOGY The chemical analyses of chemicals that are found in biological samples. TRACE EVIDENCE Very small pieces of evidence used to investigate alleged crimes. UNKNOWN Refers to those deaths that are related to factors that cannot be determined.

22 1.2 Introduction to Forensic Anthropology and Odontology 14 Section Two: Introduction to Forensic Anthropology and Odontology 2 List the characteristics that can be determined by forensic Defi ne and discuss forensic anthropology anthropologists in regards to recovered remains Defi ne forensic odontology and discuss its usefulness in the medico-legal community Physical anthropology is a unique discipline that has contributed much to forensic investigation over the last two centuries. Physical anthropology is also known as biological anthropology. Physical anthropologists study biological evolution, genetic inheritance, human adaptability and variation, primatology, primate morphology and the fossil record of human evolution. Forensic sciences, including forensic anthropology, are becoming more and more popular due to various television dramas, novels, and movies. This section gives a more detailed overview on forensic anthropology and forensic odontology (or dentistry). What is forensic anthropology? Forensic anthropology is the application of physical anthropology and its techniques to assist in the investigation of human (and often nonhuman) remains in order to provide more information to a medical examiner or coroner s office. The investigation of human skeletal materials answers many questions about what may have happened to a person or group of people. While a forensic anthropologist cannot give a legal opinion on the CAUSE of death, they do offer information that can be used to understand the mode or manner of death. While the cause of death can be tied to many different contributing factors, the primary cause of death is failure of the heart to supply the amount of blood flow necessary for life. Of course, this may be related to drugs, trauma, disease, etc. But only a medical examiner (or coroner in some jurisdictions) can make that legal definition in most jurisdictions. However, forensic anthropologists can use evidence of skeletal trauma and condition to understand the mode of death. There are five different modes (manners) of death: natural, suicide, homicide, accidental, and unknown. It should be pointed out that these are general definitions and specific jurisdictions may differ from those discussed here.

23 15 Introduction to Forensic Anthropology and Odontology 1.2 Natural refers to conditions that are naturally occurring and are usually related to age or disease. Suicide refers to those deaths that are related to a victim causing their own death through either direct or indirect means. Homicide refers to a victim s death related to the direct and deliberate actions of others. Accidental refers to deaths that are related to various causes that cannot be related directly or indirectly to specific individuals. Finally, unknown refers to those deaths that are related to factors that cannot be determined. What are the main classifi cations for mode/manner of death? CONCEPT CHECK ONE What can a Forensic Anthropologist tell investigators? The information that can be provided by the forensic anthropologist can be illustrated in the form of questions. The answers to those questions are used to develop a biological profile of the victim, along with other relevant records, such as medical and dental records. A biological profile is the reconstructed life and death of the individual, including biological sex, chronological age, ante-mortem trauma, ancestry, and stature. Are these remains human? Most of the remains that are seen by a forensic anthropologist are usually animal bones found by responsible citizens who turn them over or report these remains to the local police. Most mammals have the same general type of bones and many do look alike (even a trained forensic anthropologist may mistake a skeletonized bear paw with a human hand). Many forensic anthropologists either rely on colleagues who have training in comparative osteology or faunal (animal) analysis; some forensic anthropologists may even have extensive

24 1.2 Introduction to Forensic Anthropology and Odontology 16 training in the identification of animal bones. Additionally, through the analysis of bone histology (its microscopic structures), we can examine the type of bone and its structure. Human and non-human bones differ in their structure. How many people are represented? Mammals have what is called a bilateral (or paired) skeleton. This means that mammals have a left side and a right side. Because of this situation, it is possible to distinguish bones from different sides of the body (for example, while the left and right humerus are similar, we can tell which side they came from based on the different orientations of the bone itself). Forensic anthropologists can count the number of left and right bones of the same kind (left and right femora or thigh bones for example) and see what the minimum number of people (Minimum Number of Individuals or MNI) are needed to account for this number. Other sources of information that can be used to get a better idea of the MNI are bone size, age, and general condition). What is the biological sex of this person? One of the most important aspects of the skeleton that need to be ascertained is the biological sex of the individual. This differs from the gender of the individual as gender may refer to outward sexual attitude, characteristics, clothing, and behavior while, in general, biological sex is usually male or female (there are some exceptions to this, of course). Primarily the differences between males and female are manifest in the pelvic region (this should go as no surprise as the female pelvis has evolved to birth a large-brained child as well as walking erect) as well as musculature marks on bones such as the femur (upper leg) and occipital/nuchal (neck) region of the skull. How old was this person? People change as they age. We can usually look at a person and see what age, even generally, they are. This same situation occurs in bone tissue. By looking at different bones, we can get

25 17 Introduction to Forensic Anthropology and Odontology 1.2 a general idea of the age of a person. Up until around age 25, we look at growth of tissues, like long bones of the arms and legs. As we get older, those bones get longer because they are actually composed of three or more pieces (mostly the two ends on a shaft of bone). As we age, those bones grow and when we get to a certain age, the pieces fuse together and no longer grow. This age is different for males and females as well as different ethnic populations. After about age 25, we are looking at degeneration or damage to bone tissue. This wear-and-tear on bones can be calculated and give us a rough idea of the age of the individual. Important bones for this include the hip bones, especially where the two sides of the hips rub against each other or other bones. What was this person s ancestry or ethnicity? Most modern physical anthropologists don t use concepts such as race because they recognize that variation in the human appearance (phenotype) as a continuum. Race is a social concept that is applied and related to appearance, religious, as well as economic settings. However, forensic anthropologists routinely use this concept in discussing skeletal remains because race is a social concept and used in today s society to describe individuals. Thus, if we have a missing person s report and we are attempting to identify possibilities, we have to use these concepts. For example, if we have a report that says an individual is white we must be able to distinguish this, if possible, based on skeletal information. A lot of research in forensic anthropology has been focused on defining these sociallydefined characteristics as they may appear in bone tissue. How tall was this person? Basically, if a person has long bones, he or she was probably a tall person. But through research done over the past 100 years, we can take a measurement of a bone and determine with some certainty how tall that individual was. Of course, this varies based on ethnicity and gender. However, some bones are better to use for this analysis than others. Most of our height is related to the length of our legs, so it is better to determine the height (or stature) of an individual based on leg bones instead of arm bones (although this can be done it s just not as accurate). What is a biological profi le? CONCEPT CHECK TWO

26 1.2 Introduction to Forensic Anthropology and Odontology 18 Forensic Odontology Forensic odontology (or dentistry) includes the analysis of materials related to dentition in a legal setting. Three different aspects are the primary areas of interest: the estimation of age based on tooth development and growth, the analysis of various characteristics of teeth in order to identify specific individuals, and bite-mark analysis. ENRICHMENT SECTION For aging, forensic dentists will examine the growth sequences of deciduous (not permanent) dentition and its replacement by permanent teeth. For identification purposes, forensic odontology is the preferred method of positive identification. The comparison of after-death (post-mortem) radiographs (xrays) with before death (ante-mortem) radiographs is the primary way of identifying specific individuals. While this will be discussed more in a subsequent section, tooth restoration, including various types of fillings, caps, partial dentures, and dentures, may provide a point-by-point comparison of the shape of various fillings. Other forms of comparison include the shape of roots and pulp cavities. Due to the individual shape of teeth as well as modifications that occur during life, primarily breakage, it is possible to identify someone based on bite marks. Bite marks are very personal lines of evidence that are often left on victims of physical and/ or sexual abuse, particularly children. Thus, much of bite-mark analysis done by forensic odontologists is related to child abuse. Defi ne the terms forensic anthropology and forensic odontology. Summarize how they are similar and how they are different from one another. CONCEPT CHECK THREE

27 19 Introduction to Forensic Anthropology and Odontology 1.2 VOCABULARY FORENSIC ANTHROPOLOGY The application of physical anthropology and its techniques to assist in the investigation of human (and often non-human remains) in order to provide more information to a medical examiner or coroner s office. FORENSIC ARCHAEOLOGY Using the techniques of archaeology to find out what happened on a recent crime scene in order words, to reconstruct all the human and other behaviors that have caused a scene to look the way it does when an investigator arrives on the scene. FORENSIC ODONTOLOGY (or dentistry) includes the analysis of materials related to dentition in a legal setting.

28 1.3 Forensic Archaeology and Crime Scene Investigation 20 Section Three: Forensic Archaeology and Crime Scene Investigation anthropology Discuss the importance of preserving the scene during an investigation Describe how archaeological methods are used analyze evidence at a scene Defi ne forensic archaeology and compare it with forensic 3 This section presents basic information on the proper use of archaeological techniques in the investigation of crime scenes. The primary concern of crime scene investigation is the collection and preservation of evidence. Because archaeology is concerned with the context, or physical setting, of material evidence, it is uniquely qualified as a scientific discipline to be used in the collection of legal evidence. Additionally, one of the main principles of archaeology focuses on the temporal (time-based) reconstruction of past events and behavior. Through the examination of the physical relationships of evidence to the landscape and to other pieces of evidence, it is possible to reconstruct the events that led up to the creation and modification of this crime scene. What is Forensic Archaeology? In North America, archaeology is generally considered one of the four sub-disciplines of anthropology. Anthropology is the study of human diversity, both cultural and social as well as physical. Archaeology is the reconstruction and interpretation of past human behavior based on the material remains of that behavior. The other sub-disciplines of archaeology include physical anthropology (the study of human and related primate biology as well as the origins of the human species), cultural or social anthropology (the study of human societies and cultural interactions), and linguistics (the study of human verbal and non-verbal communication). Forensic archaeology is the application of archaeological techniques and strategies to sites or scenes in a medical or legal setting. These settings can include any sort of legal setting. While forensic archaeology has primarily been used for the excavation and recovery of human remains in various settings (isolated burials to mass disasters), it can have other uses, for example, in the investigation of arson. We will focus more

29 21 Forensic Archaeology and Crime Scene Investigation 1.3 on the aspects of forensic archaeology used to investigate and record outdoor crime scenes. Forensic archaeology is a relatively new term applied to something that is basically standard archaeology, the appropriate excavation and recovery of sites or remains, which has been used for years to assist police. In the old days, a forensic anthropologist would often call upon an archaeologist colleague to assist in the recovery of human remains, usually the excavation of a clandestine (or hidden) grave. This was often a natural collaboration between two professionals, and allowed a great deal of information on the grave and other types of sites to be recovered. The types of information recorded were different to most standard police investigators, but the results were the same - to answer the questions: What happened here? Today, many archaeologists have specialized in a type of consulting archaeology that focuses on serving the legal and law enforcement community. One of the main goals of archaeology is to find out what happened in the past usually we are talking about a couple hundred to several thousand or more years. But in forensic archaeology, we want to use the techniques of archaeology to find out what happened on a recent crime scene in order words, to reconstruct all the human and other behaviors that have caused a scene to look the way it does when an investigator arrives on the scene. These kinds of behaviors can relate to the initial crime and anything (such as animals modifying a set of human remains) that may alter the initial crime scene and need to be taken into account to reconstruct the crime. This portion of the module deals with forensic archaeology, while other portions deal with the analysis of possible human and human biological evidence through forensic anthropology. So what s the difference? Well, it depends on your point of view. In this course, these two disciplines are viewed separately primarily based on the learned skill set or experience of the investigator or analyst that is necessary for different scientific observations and interpretations. In some countries, universities or colleges, or even official government titles, the two terms are used interchangeably. That seems confusing! Here we will say that forensic archaeology uses archaeological techniques and relates to material evi-

30 1.3 Forensic Archaeology and Crime Scene Investigation 22 dence and understanding the physical context of evidence, while forensic physical anthropology concerns the medical and legal examination of the physical remains of humans, particularly hard tissues such as bone and teeth. Forensic archaeology focuses on understanding the formation of assemblages of biological and/or material evidence created by criminal activity within a broader context of a landscape. These collections of evidence are the result of human behavior after they have been left (or deposited) on the landscape. Natural processes, including decomposition, gravity (colluvial), water movement (fluvial), as well as insect and animal activity result in modifications to the scene and human remains. Insects are part of the decomposition process in because they act as scavengers and carnivores, contributing to the scattering of remains. This is part of understanding the postmortem interval. The postmortem interval is an important aspect of reconstructing a crime and can include such observations as the degree of decomposition as well as the stage of insect growth (this is usually accomplished by a specialist, known as a forensic entomologist). Archaeological endeavors include the recovery and recording of material and/or biological evidence that preserves the integrity of the spatial and temporal context (space and time components) of the scene. Forensic archaeologists are best used at all outdoor crime scenes where the physical evidence is becoming incorporated into the natural environment. ENRICHMENT SECTION Insects are part of the decomposition process in that through their scavengers and carnivores scattering remains. This is part of understanding the postmortem interval. The postmortem interval is an important aspect of reconstructing a crime and can include such observations as the degree of decomposition as well as the stage of insect growth (this is usually accomplished by a specialist, known as a forensic entomologist). There are well-established processes that insect life follows once a living thing has died. These processes are dependent on the conditions the corpse is exposed to, including light, dark, heat, cold, dry, and moist. Flies are most active in bright light, slowing down in cloudy conditions and being inactive at night. Flies are also most active in hot conditions. Heat also seems to speed up larval growth and species succession. Different species of insects are attracted to different conditions. For example, blow fly maggots stay away from moist areas while other insects, such as wasps, butterflies and some beetles are attracted to the moistest areas. However, the number of cells that express the CD34

31 23 Forensic Archaeology and Crime Scene Investigation 1.3 antigen has been found to correlate with successful bone marrow and cord blood transplantation. Dr. Jerry Payne described 6 levels of decay in his studies of the effects of insect activity on dead piglets in the 1960s: fresh, bloated, active decay, advanced decay, dry decay, and remains. These levels of decay are based on the fact that the different gases formed at each stage of decay attract different types of insects. Fresh refers to the newly dead animal. The insects have not yet become active. Bloated refers to the state where gas builds up inside the carcass and it becomes bigger because of the pressure of the gas. Blow flies and flesh flies become active at this stage. They lay eggs and feed on the flesh. Active decay occurs when the fly larvae get through the abdominal cavity and deflate the corpse. This results in liquids leaving the corpse and soaking into the ground, which attracts rove beetles and clown beetles, which bury themselves beneath the carcass. The odor of decay also attracts house flies. As the fluid begins to ferment, emitting a sweet smell, butterflies, bees and moths are also attracted to the scene. Advanced decay is starts when most of the soft tissue is gone. The odor decreases except for some ammonia smell. The maggots begin to abandon the carcass and were preyed upon by more beetles. At the end of this phase, the carcass looks dry. Dry decay starts with a noticeable shift of odor to that of wet fur and old leather. New types of insects begin to arrive: skin beetles, hide beetles, checkered beetles, as well as mites, roaches, soil beetles, springtails, and gnats. The remains phase consists of hair, bits of dry skin, bleached bones, and teeth. Centipedes and millipedes live under the bones and ants may visit to take away skin or hair scraps. ENRICHMENT SECTION

32 1.3 Forensic Archaeology and Crime Scene Investigation 24 Describe the differences between forensic anthropology and forensic archaeology. CONCEPT CHECK ONE Protecting the Integrity of the Scene In order to investigate a scene, an investigator must first ensure the protection of the scene and its evidence. We need to control the amount of disturbance that can occur from unauthorized individuals or natural events. This can be a very difficult job as many people want to have access to a scene. Only those individuals such as the team leader and the investigators should have primary access to the scene. All others, including the media and even possible family members of the deceased, should be kept in a buffer zone, well away from the primary zone of investigation. The primary activity of investigators is the recovery of evidence and recording of the three-dimensional location of each piece of evidence. Following this documentation, this evidence must be packaged in a way that will preserve it physically as well as in an evidentiary manner, especially if it must travel some distance to the analysis facility or laboratory. The evidence must be protected and secured in a manner that protects its contamination and integrity. Usually this is done through packaging in paper or plastic bags; these evidence containers are then labeled with unique information including a case number or scene designator as well as the date and name or initials of the investigator. In summary, the primary goals of forensic archaeology while at a scene include: Locate scene(s) Identify, record, and collect contextual evidence, which is any evidence that has meaning in relationship to the overall scene. For example, a bat would be an interesting piece of contextual evidence if the victim died of blunt force trauma. Identify, record, and collect physical evidence, which includes weapons, clothing, and anything else that could be relevant to the recovery.

33 25 Forensic Archaeology and Crime Scene Investigation 1.3 Why is it important to protect a forensic/crime scene until the investigation is completed? CONCEPT CHECK TWO Archaeological Methods The key assumption concerning all forms of archaeology is that it is destructive in nature. To excavate a site is to destroy it. You can never place all the dirt and other artifacts back in exactly the same places. The very act of excavation destroys the very information we seek. Thus, record keeping and documentation in the form of photography, videography, maps, sketches, and notes are essential and actually form the basis of the evidence of your activities at a scene. The various types of documentation should be treated like other forms of evidence and may be subpoenaed into court or may be needed to verify the conclusions offered in court. Key lines of evidence include the spatial relationships between individual items of evidence and spatial relationships between items of evidence and their physical setting. These relationships can only be observed when the evidence is in situ that is, in their original placement as found. The excavation team may be the only people ever to see these relationships of evidence to each other and their physical setting. This is why the documentation must be done immediately and with a high degree of accuracy. The quality of the excavation can be measured by the amount of information that is collected as well as the number of items of evidence. Discuss how archaeological methods are used to support crime scene analyses and why use of proper methodology is important to maintain the integrity of the fi ndings? CONCEPT CHECK THREE Archaeological methods are crucial for detailed and accurate collection of data and analysis of a crime scene. The methods used to excavate ancient cites have been adapted for use in excavating crime scenes or burial sites. Forensic archaeology is just one branch of forensic sciences that support law enforcement officials who are working to solve crimes.

34 1.3 Forensic Archaeology and Crime Scene Investigation 26 VOCABULARY ANTHROPOLOGY The study of human diversity, both cultural and social as well as physical. ARCHAEOLOGY The reconstruction and interpretation of past human behavior based on the materials remains of that behavior. ASSEMBLAGE A specific group of items, often found together; in these terms a group of evidence found together at a scene. COLLUVIAL Movement of materials through processes related to gravity, such as sliding down a hill slope from an original location. CONTEXT The physical setting of evidence and the spatial relationships between those items; how the items relate to each other and their environmental setting. FORENSIC ARCHAEOLOGY The application of archaeological techniques and strategies to sites or scenes in a medical or legal setting. FLUVIAL Movement of materials through processes related to flowing water, such as sheet wash after a rain storm or a stream/river. FORENSIC ENTOMOLOGY The study of insects and their growth cycles related to medical and legal investigations; this is usually done to determine the postmortem interval at a scene. IN SITU A Latin term that means in place. In archaeology, this implies that the evidence is still in its original place and context as it was upon discovery and that it has not been moved prior to its documentation. STRATIGRAPHY The study of or physical relationship of strata (sing. Stratum) that deals with the formation, composition, distribution, and succession of strata.