Forensic Science - Case Study Example

Application of Forensic Science Mass disasters usually happen in a thunderclap. In cases involving airplane crashes, floods, fires, and bombs, which are all virtually instantaneous, the medical examiner or coroner is suddenly faced with a phalanx of the dead with essentially no warning. The task of forensic science is to identify victims and causes of mass disasters. A traditional definition for "mass disaster" is that it is any event resulting in six or more deaths at the same time and in the same place from one basic cause (Taylor, 2005). A more recent definition is attuned to local conditions: a mass disaster is an event that causes such a number of essentially simultaneous deaths in the same location that the facilities and personnel available to handle and process them are overwhelmed. Mass disasters are also usually accompanied by a large number of injuries, and that the injured must be speedily removed from the scene, stabilized, and transported to medical facilities for further treatment (Housley, 2006). All of this must be done while the law enforcement authorities secure the scene to block access to looters, those who would "just like to help," and the morbidly curious. Forensic science is closely connected with other sciences which help to identify victims and causes of mass disasters. The main fields include DNA and TrueAllele ® Technology, dental identification of victims, forensic pathology and forensic engineering, forensic anthropology and toxicology, entomology and disaster management. The stage of scene investigation involves photograph of a place and bodies dozens of times, from every angle, making sure to capture every item and surface in at least a couple of photographs. They also may shoot video narrating as they go (Payne-James 2004). This video is being sent live to technicians in the crime lab. Usually, a folder containing all the necessary paperwork is placed with each and accompanied the body through initial processing. Each body is then assigned a case number, weighed, and placed in the inside cooler or the refrigerated truck outside. A master chart shows the location of each body and the status of the work done on it (Payne-James 2004). The main method used by forensic specialists is autopsy. There is little the medical examiner can do at the scene. Back in the office and autopsy room, an examiner will examine the body in minute detail, looking for evidence of injuries that were inflicted right before or even after death. The examiner will remove from the body any hairs or fibers that do not appear to be the victims (Costello 2006). The examiner will search for needle punctures and examine the victims hands. Any skin under the fingernails or any hairs or fibers on his hands can be valuable evidence. The medical examiner will remove and weigh the victims internal organs. The limitation of this method is that after mass disasters only parts of bodies remain (Housley, 2006). The skills of the odontologist can be utilized for a positive identification only when there are adequate antemortem records for comparison with a body. While these are usually charts prepared by the victims dentist, records may also consist of x-rays of the mouth and teeth, summary written records, or, on occasion, photographs that can be matched to the victims teeth (Bowers, 1995). Forensic odontologists can make very rapid identifications from such records and their input is invaluable in the processing of victims of mass disasters. Even without dental records, odontologists can provide useful information about the quality and origin of the dental care, as well as offering some perspective on the demography of the decedent. While skeletons often yield only the most minute clues about the time and manner of death, persistence and some luck often can lead to positive identification of the remains. If the records of those who are missing are good enough, forensic anthropologists and odontologists (forensic dentists) can identify remains with remarkable accuracy. Dental records provide the best identification, followed by X rays of injuries that have healed (Bowers, 1995). Working with as little as a handful of bones and the crowns of one or two teeth, forensic scientists have identified the victims of disasters new and old, homicide victims, those who “disappeared” during the brutal reign of terror in Argentina, and victims of “ethnic cleansing” in the former Yugoslavia, Rwanda, and other countries (Housley, 2006). In a celebrated case, forensic scientists were instrumental in identifying the notorious Nazi Angel of Death, Josef Mengele. In addition, by using both forensic odontological and anthropological techniques and DNA samples, investigators have been able to match the tiniest remains to almost all of the victims of major disasters in the 1990s, including the ValuJet crash in the Everglades, the TWA explosion off the coast of Long Island, and the Oklahoma City bombing. When skeletal evidence is all that remains, each of the bodys 206 bones and 32 teeth can tell a story about the life of its former owner—that persons osteobiology (Housley, 2006). Injuries are recounted through healed fractures. Illness can be inferred from such deformities as bowed legs (a sign of rickets), the telltale shortness of a polio victims limbs, the skeletal damage caused by such diseases as syphilis or tuberculosis, or by bone infections such as osteomyelitis. The injuries involved in skull fractures can also reveal potential controversies in forensic interpretation (Housley, 2006). Racial features also differ. Forensic anthropologists often use features of the eye sockets and nose to categorize people in one of three racial groups: Mongoloid (broadly defined as Asian), Negroid (African), and Caucasoid (European). In Negroids and Mongoloids, the ridge of the nose often is broad in relation to height; in Caucasoids, it is narrower. The skull also gives clues to a skeletons age. The basilar joint (where the two main bones of the skulls underside meet) fuses in the late teens. Another clue to age is in the long bones of the arms and legs (Housley, 2006). For instance, where the knob and shaft of the femur (the large upper leg bone) meet any areas of cartilage, the degree of calcification indicates maturation. Incomplete calcification signals that full maturity has not been reached. Once the skeleton is fully adult, microscopic analysis of bone degeneration is necessary to try to pinpoint age. Certainly one important limitation of this method is that the forensic anthropologist cannot analyze skeletal material that he or she does not have. Recovery is thus the essential first link in skeletal analysis. If no more than the skull and femur had been found of Ms. Garcia, the identification could still have been made on the basis of the skull x-rays and a dental comparison, but would that comparison ever have been made when the operating hypothesis was that the remains were probably male rather than female? Perhaps not. The Garcia case also reminds us that one of the persistent problems in the identification of the skeletons of the young is that they are less likely than older people to have undergone medical treatment. Until and unless a person seeks treatment for a broken bone or some other ailment, no medical records will exist. Youngsters and even young adults are infrequently x-rayed and as a consequence useful antemortem records will rarely be found for children. We were fortunate that the OMI investigators were able to ferret out, first, the skull x-ray that made identification possible and, later, the dental x-rays that confirmed it. Forensic anthropologists are often challenged by their cases to probe into the misty realms of the unknown. The work recounted here consumed many hours of looking at other skulls, required library and lab work and the cooperation of others. But such challenges also provide forensic anthropologists with an opportunity for testing assumptions and validating methods. Taking these small steps into the unknown leads to new discoveries about the skeleton. Many details of skeletal anatomy and development remain to be uncovered (Housley, 2006). The FBI has conducted hair and fiber analysis since the 1940s, and each year its examiners consult on more than 40,000 cases for local law-enforcement agencies. Because of the small size of trace evidence, the difficulty of establishing individualization and comparison, and the need to establish statistical probabilities that the evidence in question actually was in contact with a victim or an accused, this evidence often is not collected and, even when it is, it is often either not used at all or not used properly in court. There are four varieties of fibers: animal, vegetable, mineral, and synthetic (Housley, 2006). Microscopic examination is done using a comparison microscope, which has two plates for samples that are being compared, and a polarized-light microscope and a fluorescence microscope, both of which allow the examiner to look at the fiber under conditions that negate the effect of dye, so that true characteristics can be determined. Polarized-light microscopes act like polarized sunglasses, removing certain light waves from the spectrum that passes through the lens to the viewers eye. Fluorescent microscopes remove other light waves. In England, the Central Research Establishment of the Home Office Forensic Science Service has created a database of more than 13,000 fibers and their frequency of appearance. Again, the limitation of this method is inadequate databases and limited access to databases of other countries (Housley, 2006). For instance, in the early 1970s in northern Colorado, the Big Thompson River, already swollen with heavy rains, was hit with a torrential downpour around Estes Park. A wall of water scoured the steep canyon, leaving more than thirty dead. With the aid of forensic anthropologist, all were identified. In this flood, some bodies were carried miles downstream and badly battered, adding to the difficulty of identification. In the summer of 1993, great floods again ravaged the Midwest, disrupting transportation, communication, and peoples lives. An unexpected side-effect was what might be thought of as a historical mass disaster (Housley, 2006). While eight hundred bodies ought to qualify as a mass disaster, the fact that they had been dead and buried for thirty to seventy years prior to the disaster took a little edge off of the urgency that normally attends such affairs. These "bodies" ranged from isolated single bones to virtually complete bodies in coffins. They were dated by the type of coffin and the artifacts found with them. In under two weeks, the seven-person anthropology team examined 407 individuals, making two positive identifications and finding many examples of diseases both of bones and soft tissue. They found not only skeletonized but mummified remains and bodies with soft tissue still left, but could get no correlation between time of interment and the condition of the body (Okoye & Wecht 2007). DNA analysis of victims of mass disaster is considered the most beneficial and accurate. DNA typing quickly acquired the title of “genetic fingerprinting” (Okoye & Wecht 2007). Police and prosecutors often tout the technique as foolproof, the best possible way to match crime scene body-fluid samples to a particular victim or suspect. If DNA can be extracted from a specimen, it is then mixed with a restriction enzyme that cuts the DNA chain at specific sites. The restriction fragments that are created by this process vary in length, and a few of them contain the polymorphic DNA segment (Kaye, 2006; Housley, 2006).). These scientists argue that the chances are usually one in millions or billions that two individuals would present an identical DNA print; the odds vary, depending on the population in question because there are racial and gender differences in polymorphic strands, and various features are more common or less so. Thus, these scientists believe there is virtual certainty that the accused is guilty. The main limitation is inadequate databases: many countries do not have DNA databases at all which creates problems for forensic scientists (Kaye, 2006; Sasser, 2000). Fingerprints are often used as the main identification tool. The yare unique; they are proof positive of identity. Millions of Americans have their fingerprints on file: The military takes fingerprints of every member, to aid in identification after death, while the intelligence agencies routinely fingerprint employees as an aid in any subsequent espionage or counterespionage investigation that might need to be conducted. Lawenforcement agencies routinely fingerprint everyone who is arrested and charged with a crime. This system produces the best few possible matches, which then can be examined closely by trained human fingerprint analysts (Housley, 32). AFIS (automated fingerprint identification systems0 can match reference fingerprint cards either to fingerprint cards taken at the time of a new arrest or to latent prints—fingerprints that occur in the normal course of touching objects—removed from a crime scene. For fingerprints on paper, cardboard, unpainted wood, and other porous surfaces, fingerprint technicians often use chemical fuming techniques. Iodine fuming has been used for more than half a century. Iodine crystals vaporize rapidly when subjected to heat and produce violet fumes that are absorbed by skin oils. When a sample is put in an iodine fuming cabinet or “shot” with an iodine fume gun, any latent prints will absorb the iodine fumes and become visible, appearing yellowish-brown against the background. The prints are visible only as long as the fumes last, so they must be photographed immediately. In addition, old prints often dont develop well using iodine, and the vapors are toxic to the technician and corrosive to other materials (Payne-James et al 2004). Physical identification can be used to identify victims of mass disasters. They involve tattoo, piercing, birthmakes, scars, etc. every person have specific physical characteristics, including a particular head size and shape. For instance, tattoos allow to identify social position of a person and background, possible name or orientation, etc. Tattoos help to identify family and lifestyle, country and occupation (Bowers, 1995). For instance, after the tsunami in Taiwan forensic professionals were faced with real difficulties to identify victims of the disaster. Difficult conditions and great number of victims worsened the situation. Over 1000 UK officers went to work on the case estimated total deaths 297,000. The main problems were difficult conditions of work, different cultures, multi-national response and inadequate international databases. The main techniques used were odontology, fingerprints and DNA analysis. UK police and government spent Ј50 million pounds, but results were not sufficient. Out of 297,000 bodies examined only 180 were identified. Thai soldiers were the first emergency forces involved in operations. Unique culture, rituals and religion raised cultural concerns and disrupted identification. Like in case of the tsunami bodies were initially kept in the hot sun (48 degrees) outside which accelerated decomposition process. Initial examination could be physically based but this was being lost due to decomposition. Fingerprinting was used as one of the main tools of identification but as most bodies had come into contact with water and decomposed the results were inaccurate. The boiling method was used to improve the results. With tsunami case, DNA examination resulted in 6,000 failed results as the bodies were so badly decomposed. Odontology was the most effective method in victims’ identification. Thus, the main problem was that the Thai population did not have dental records and a database. However, it was later discovered that the locals had an extra bone in the mouth, which was used to ID them. In sum, mass disasters cannot be predicted, but the task of forensic science is to develop new methods of victims identification and scene investigation. The most important is that the medical investigators facility should be well planned and running smoothly. With enough room and good equipment available to process and autopsy the bodies, procuring another location and moving supplies and equipment there is unnecessary. The impact of disasters can be moderated somewhat by extensive and careful advance planning. By this means, it is possible to ameliorate some of the widespread confusion that descends like a blanket when disaster strikes. Every method and technique has certain limitations which prevent forensic professional from objective and accurate investigation. In this case, it is important to improve communication and relationships between different fields of forensic science and bring in outside experts. Bibliography 1. Bowers, M.C. 1995, Manual of Forensic Odontology. Forensic Pr. 2. Costello, B. R.H., Axton, J., Gold, K.J. 2006, A New Forensic Picture Polygraph Technique for Terrorist and Crime Deception System. Journal of Instructional Psychology, 33 (4), p. 230. 3. Housley, J. 2006, Treating Victims of Mass Disaster and Terrorism. Hogrefe & Huber Publishing. 4. Kaye, D.H. 2006, Behavioral Genetics Research and Criminal DNA Databases. Law and Contemporary Problems, 69 (1-2), pp. 259-260. 5. Okoye, M. I., Wecht, C. H. 2007, Forensic Investigation and Management of Mass Disasters. Lawyers & Judges Publishing Co. Inc. 6. Payne-James, J., Byard, R., Corey, T. 2004, Encyclopedia of Forensic and Legal Medicine. Academic Press Inc., U.S. 7. Sasser, R. 2000, DNA Databases: When Fear Goes Too Far. American Criminal Law Review, 37 (3), p. 1219. 8. Taylor, A.J.W. 2005, Management of Dead Bodies in Disaster Situations. New Zealand Journal of Psychology, 34 (2), p. 135. Read More