Douglas P. Lyle

Forensics For Dummies


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into a home to avoid leaving fingerprints, they wear condoms in rapes to avoid leaving behind DNA evidence, and they take other steps to avoid detection. Fortunately, a little knowledge is a dangerous thing, and as you see in the remainder of this book, criminals may avoid leaving behind one type of evidence while ignoring other, equally damning, evidence. And that’s a good thing.

From Analyzing Blood to Identifying Bugs: Forensic Science Specialists

      If you need to find out how a victim died or identify a piece of a plant found at a crime scene, you call on a forensic scientist trained in pathology or botany, respectively. Professionals who work in the various forensic biological sciences are among the most highly trained and skilled members of the forensics team. They include the following:

      ✔ Pathologist: A forensic pathologist is a licensed physician with specialty training in pathology, which deals with the nature of disease and the structural and functional changes it causes in the human body. In addition, the forensic pathologist takes subspecialty training in forensic pathology, the application of pathological science to the law.

      The forensic pathologist is in charge of the body and all the evidence that is gleaned from its examination. He uses the autopsy, police report, medical records if indicated, suspect and witness interviews, the results of crime lab evidence evaluations, and much more in the pursuit of answers. The forensic pathologist also examines living victims to determine the causes and ages of injuries, particularly in cases of assault, rape, or abuse. Part III of this book focuses on forensic pathology.

      ✔ Anthropologist: The forensic anthropologist studies human skeletal remains to determine the age, sex, and race of the deceased, identify any illnesses or injuries that the victim may have suffered, and to estimate the time of death. The forensic anthropologist examines not only the recovered bones, but also the location and circumstances in which they were found. Toxicological, chemical, and DNA analyses also are used by the forensic anthropologist. Other responsibilities may include identifying victims of mass disasters and those interred in mass graves. You can find out more about forensic anthropology in Chapter 10.

      ✔ Odontologist: A forensic odontologist (or forensic dentist) helps identify unknown corpses by matching dental patterns with previous X-rays, dental casts, or photographs. Because dental enamel is the hardest substance in the human body, forensic dental services can help with identifying homicide victims, victims of mass disasters, and skeletal remains. Forensic odontologists are called upon to match a suspect’s teeth with bite marks on the victim or on food products such as cheese or apples. Chapter 10 tells you more about forensic odontology.

      ✔ Entomologist: Entomology is the study of insects. The forensic entomologist uses knowledge of the life cycles of flies and various other insects that feed on corpses to determine the approximate time of death. Likewise, the forensic entomologist uses knowledge of insect habitats to determine whether a body has been moved from one location to another. Find out more in Chapter 11.

      ✔ Psychiatrist: The forensic psychiatrist may be asked to address someone’s sanity or competence to stand trial, sign documents, or give informed medical consent. In suicide cases, forensic psychiatrists may be asked to conduct psychological autopsies to determine possible motivations of the deceased. A forensic psychiatrist may also be asked to provide a psychological profile of an unknown perpetrator. Check out Chapter 4 for the lowdown on forensic psychiatry.

      ✔ Serologist: The serology lab deals with blood and other bodily fluids such as saliva and semen, identifying the presence or absence of antigens and antibodies in those fluids. Blood typing, paternity testing, and in some labs even DNA profiling are conducted by the serologist. Turn to Chapter 14 for more.

      ✔ Toxicologist: Toxicology is the study of drugs and poisons. The forensic toxicologist determines whether drugs or poisons are present in the living and the deceased, often to assess how those substances contributed to aberrant behavior or death. The forensic toxicologist also determines whether drivers were intoxicated or workers violated company drug-use policies. Check out Chapter 16 for the full scoop on toxicology.

      ✔ Botanist: Examining plant residues, one of the tasks performed by a forensic botanist, is sometimes crucial to solving a crime. Plant fragments, seeds, pollen, and soil may be used to place a suspect at the crime scene. For example, pollen found on the clothing of a suspect can be matched to that of a rural crime scene, thus suggesting that the suspect was in the same area. Plant and pollen evidence also can reveal that a corpse has been moved. Find out more about forensic botany in Chapter 17.

Forensic Investigation’s Head Honcho: The Medical Examiner

      Coroners and medical examiners are charged with determining the cause and manner of death, overseeing the analysis of evidence, and presenting their findings in court. They often work with the police to help guide ongoing investigations by supplying them with the results of any forensic tests that have been performed. The responsibilities of these two offices cover every aspect of investigating a death.

      

The terms coroner and medical examiner (ME) are often used interchangeably, but they are, at least theoretically, quite different (see the following section for details). Regardless of which system is employed, in death investigations many of the duties of the coroner or the ME are similar. I use the term ME throughout the remainder of this book, even though some jurisdictions employ coroners for handling the legalities of death.

       Looking at two forensic systems

      In the United States, two types of forensic investigative systems exist: the coroner system and the medical examiner system. Fortunately, the trend is toward the latter system, though it is far from perfect.

      The coroner is an appointed or elected position that, unfortunately, requires no special medical or forensic skills. The sole criterion seems to be the ability of the person seeking the office to be elected or appointed. The coroner could be the sheriff, a newspaper publisher, a neighborhood café owner, or the local funeral director. They too often possess little or no medical training or experience.

      During the past several decades, the politics of the office have evolved so that today many jurisdictions require the coroner to be a licensed physician. He may be an internist, an obstetrician, or a dermatologist but doesn’t necessarily have to be a pathologist and certainly not a forensic pathologist. Thus, the coroner may not actually be qualified to perform many of the duties of the office. This deficiency led to the creation of the medical examiner system.

      

In theory, a medical examiner (ME) is a physician licensed to practice medicine, and many are trained in pathology and forensic pathology, meaning that ideally they are medical doctors with special training in pathology and experience and training in forensic pathology. A forensic pathologist is a clinical pathologist who has taken extra forensic training. He usually heads up the crime lab and oversees all aspects of death and criminal injury. The heart of the forensic pathologist’s job is performing forensic autopsies, which are designed to help determine the cause and manner of death.

      In an ideal world, every jurisdiction would have a medical examiner who also is a board-certified forensic pathologist, qualified to fulfill all the duties of his office. The world, as you know, is not ideal, and even today in many jurisdictions nonmedically trained coroners and MEs continue serving as local public officials charged with investigating death. This solution is a practical, money-saving one because these areas simply don’t have the population base to justify the presence of a forensic pathologist. Under these circumstances, the coroner/ME has several alternatives for acquiring