Forensic Science

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Forensic Science
1.1Overview on Forensic Science
Forensic science (often shortened to forensics) is the application of a broad spectrum of sciences to answer questions of interest to a legal system. This may be in relation to a crime or a civil action. The word forensic comes from the Latin adjective forensis, meaning "of or before the forum." In Roman times, a criminal charge meant presenting the case before a group of public individuals in the forum. Both the person accused of the crime and the accuser would give speeches based on their sides of the story. The individual with the best argument and delivery would determine the outcome of the case. This origin is the source of the two modern usages of the word forensic – as a form of legal evidence and as a category of public presentation. In modern use, the term "forensics" in the place of "forensic science" can be considered correct as the term "forensic" is effectively a synonym for "legal" or "related to courts". However the term is now so closely associated with the scientific field that many dictionaries include the meaning that equates the word "forensics" with "forensic science".

1.2 History of Forensic Science
1.2.1 Antiquity and the Middle Ages The ancient world lacked standardized forensic practices, which aided criminals in escaping punishment. Criminal investigations and trials relied on forced confessions and witness testimony. However ancient sources contain several accounts of techniques that foreshadow the concepts of forensic science that is developed centuries later, such as the "Eureka" legend told of Archimedes (287–212 BC). The first written account of using medicine and

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entomology to solve (separate) criminal cases is attributed to the book of Xi Yuan Lu (translated as "Washing Away of Wrongs"), written in Song Dynasty China by Song Ci (1186–1249) in 1248. In one of the accounts, the case of a person murdered with a sickle was solved by a death investigator who instructed everyone to bring his sickle to one location. (He realized it was a sickle by testing various blades on an animal carcass and comparing the wound.) Flies, attracted by the smell of blood, eventually gathered on a single sickle. In light of this, the murderer confessed. The book also offered advice on how to distinguish between a drowning (water in the lungs) and strangulation (broken neck cartilage), along with other evidence from examining corpses on determining if a death was caused by murder, suicide or an accident. 1.2.2 Modern history In the 16th-century Europe medical practitioners in army and university settings began to gather information on cause and manner of death. Ambroise Paré, a French army surgeon, systematically studied the effects of violent death on internal organs. Two Italian surgeons, Fortunato Fidelis and Paolo Zacchia, laid the foundation of modern pathology by studying changes that occurred in the structure of the body as the result of disease. In the late 18th century, writings on these topics began to appear. These included A Treatise on Forensic Medicine and Public Health by the French physician Fodéré and The Complete System of Police Medicine by the German medical expert Johann Peter Franck. In 1776 a Swedish chemist Carl Wilhelm Scheele devised a way of detecting arsenous oxide, simple arsenic, in corpses, although only in large quantities. This investigation was expanded, in 1806, by German chemist Valentin Ross, who learned to detect the poison in the walls of a victim's stomach, and by

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English chemist James Marsh, who used chemical processes to confirm arsenic as the cause of death in an 1836 murder trial. Two early examples of English forensic science in individual legal proceedings demonstrate the increasing use of logic and procedure in criminal investigations. In 1784, in Lancaster, John Toms was tried and convicted for murdering Edward Culshaw with a pistol. When the dead body of Culshaw was examined, a pistol wad (crushed paper used to secure powder and balls in the muzzle) found in his head wound matched perfectly with a torn newspaper found in Toms' pocket. In Warwick in 1816, a farm labourer was tried and convicted of the murder of a young maidservant. She had been drowned in a shallow pool and bore the marks of violent assault. The police found footprints and an impression from corduroy cloth with a sewn patch in the damp earth near the pool. There were also scattered grains of wheat and chaff. The breeches of a farm labourer who had been threshing wheat nearby were examined and corresponded exactly to the impression in the earth near the pool. Police started using fingerprints for evidence when Juan Vucetich solved a murder case in Argentina by cutting off a piece of door with a bloody fingerprint on it. Later in the 20th century several British pathologists, Bernard Spilsbury, Francis Camps, Sydney Smith and Keith Simpson pioneered new forensic science methods in Britain. In 1909 Rodolphe Archibald Reiss founded the first school of forensic science in the world: the "Institut de police scientifique" at the University of Lausanne (UNIL).

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Forensic Scientist Job Description
2.1 Overview
Forensic scientists investigate crimes by collecting crime scene evidence and using the natural sciences to analyze the data they recover. Forensic science technicians are often required to go to the crime scene and collect the physical evidence that can be found. They work closely with government officials and police detectives in order to help solve crimes. Additional tasks for forensic scientists may include:

Reconstructing crime scenes

 Collecting and analyzing DNA samples  Reporting investigative findings  Examining firearms and bullets  Analyzing textual evidence  Taking fingerprints  Interpreting laboratory findings  Keeping logs and records

Operating all laboratory equipment

Most forensic scientists specialize in certain types of evidence such as DNA analysis, firearm research and weapons testing, examining fiber, hair, tissue, or body fluid substances. They often work with chemicals, fluid samples and firearms that demand safety precautions. However, the risk of harm or contamination within these working conditions is minimal.

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2.2 Major Roles of Forensic Science in Criminal Justice Administration:
2.2.1 Crime-Solving Contributions Forensic science contributes to solving crimes through investigative activities like determining the cause of death, identifying suspects, finding missing persons and profiling criminals. 2.2.2 Determining Cause of Death Forensic pathologists determine someone's cause of death by performing autopsies. During these procedures, they examine fluids and tissues from a body to find out the cause of death and the manner of death (for example, natural causes or homicide). 2.2.3 Identifying Suspects Forensic scientists can identify suspects by analyzing evidence found at the scene of a crime---such as fibers, hairs, blood and fingerprints. These methods are also used to exonerate the innocent. 2.2.4 Finding Missing Persons Forensic artists can help find people who have been missing for long periods of time through the process of image modification. In this technique, a photograph is aged to illustrate what someone may look like years after last being seen. This is also a tool that is used to find criminals who have eluded justice.

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2.2.5 Profiling Criminals Forensic psychologists use profiling to help find suspects. By analyzing a crime scene, they are able to determine a criminal's patterns and personality in an effort to narrow the suspect pool. 2.2.6 Fingerprint Evidence Forensic scientists help collects and examine finger prints from the crime scene. This is done to find the person whose finger prints were collected from the crime scene. 2.2.7 Ballistics Forensic scientist ascertains whether a particular fire arm was used or not while committing a crime. He is also to examine the types of fire arms and ammunitions used in commission of a crime. He has also to establish the facts with regard to firing ranges, distance, direction, and angle of firing. 2.2.8 DNA Evidence In 1986, DNA evidence is used for the first time in connection with a crime by Sir Alec Jeffreys who developed the first DNA profiling test. DNA profiling was introduced for the first time in a U.S. criminal court in 1987. Based on RFLP analysis, Tommy Lee Andrews was convicted of a series of sexual assaults in Orlando, Florida. By 1998, the FBI had introduced a DNA database.

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Since then, there have been many refinements in DNA techniques and systems different types of DNA have emerged like MtDNA and so called Touch DNA.

The Importance of Forensic Science in Crime Investigations
3.1 Overview
Forensic science plays an integral role in the criminal justice system. Well-trained forensic scientists and medical examiners can be the determining factor in the ability of evidence to adequately represent the facts of a case. Forensic science can be used in almost any criminal case; however, investigations of homicide, rape, and arson are those that benefit the most from forensic science. In complicated cases, and even in relatively simple ones, the most minute of details can become paramount to a successful prosecution or defense. Forensic scientists are trained to analyze crime scenes, evidence, and personal testimony to create a visualization of how a crime occurred. An understanding of the circumstances surrounding a crime is pivotal to ensuring that the correct charges are brought against the correct person. The mishandling or misinterpretation of evidence can be devastating to the goals of the criminal justice system and can result in the wrongful conviction of innocent persons and the failure to convict the true perpetrator, which is why you need a skilled criminal defense lawyer if you’ve been convicted of a criminal offense. Conversely, correctly applied forensic science ensures that justice is served and innocent persons remain free. One person who is often overlooked in the forensic science field is the medical examiner. In homicide cases, medical examiners employ forensic science to determine the cause of death. Sometimes, the determinations of the medical examiner can show that a victim died of natural causes or by something other than a defendant’s hand. This evidence can literally be a lifesaver to a person facing a homicide charge. An example like this makes it easy to see the importance of forensic science.

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Imagine a world where criminals run freely. Detectives and police officers collect evidence much the same way as they do today, but there is one main difference. Science is not used. Due to the lack of scientific analysis, there would not be a lot of useful evidence. Without the use of science, criminals could not be convicted of their crimes, ranging from common theft to a homicidal rampage, unless there was an eyewitness present at the crime scene when the crime occurred. Murderers would continue killing, thieves would continue stealing, and drug traffickers would continue dealing. Fortunately, in today's world, science is used in solving crimes. Clues a criminal leaves behind can be traced to themselves through scientific evidence. This field of science dealing with criminal investigation is known as forensic science, which roughly means the application of science to law. Forensic science can be used to determine many things from the evidence when it is collected properly without any contamination. The people that need to learn the methods of collecting the evidence for forensic science analysis are those from law enforcement agencies that come into contact with the crime scenes frequently. Unfortunately, nine times out of ten, this person is an officer from a police department, which is lacking in evidence collection training. In other words, scientific concepts and principles are used to convict criminals of their crimes. Due to the great importance of forensic science in the conviction of criminals, the basic ideas and concepts need to be taught to officers of local police departments so that evidence can be collected without contamination in order to keep criminals from continuing to commit crimes that linger on forever in the minds of the victim’s families and the nation's psyche. Throughout history, evidence has been used to convict criminals of the crimes that they have committed. Today’s society has improved upon the methods of the past to

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bring about more precise and accurate techniques. These techniques are more commonly known as the field of forensic science. Richard Saferstein writes a more specific definition than what was previously given in his book ‘Criminalistics: An Introduction to Forensic Science’, which says that forensic science is the application of science to those criminal and civil laws that are enforced by the police agencies in a criminal justice system. Law aims at the just resolution of human conflict. Truth and justice, we might venture to say, having different aims, use different methods to achieve them. Unfortunately, this convenient account of law and science is itself neither true nor just. For law must know what the truth is within the context of the legal situation: and science finds itself ever engaged in resolving the conflicting claims of theorists putting forward their own competing brands of truth (Cowan 5). This quote roughly means that the law needs to find the truth to resolve; human conflict; and one method of doing so is to use the field of science.

3.2 The Roles of Forensic Scientist in Detection of Criminals
Forensic Science can be defined as Criminalistics Science. Along with the development of science and technology the pattern of our society has also changed to cope with the day to day development. According the criminal also often uses different techniques for commission of various crimes within our society. So it has become a problem for the law enforcing agencies to check the potentiality of crimes. For such checking the need of forensic science becomes an essential prerequisite on the part of the investigative agencies. The operation of forensic science is nothing but the application of techniques and methods of basic science techniques and methods of basic science for various analyses of exhibits associated with crimes. The scientific examination of a forensic scientist adjoins a missing link or strengthens a weakly in the chain of investigation by furnishing an impartial and

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establishes evidence, thereby helping the court to come to a conclusion regarding the criminals and their punishments. The field of study or examination of forensic scientist is very wide, diverse and unpredictable. Generally the duties and responsibilities of forensic scientist are very hazardous, onerous and risk bearing. Because they are to deal with the material exhibits pertaining to various nature of crimes such as murder, rape, blood, saliva, firearms, ammunitions, explosives, and explosives substances, liquor, hashish, opium, adulterated petrol, kerosene, diesel, etc. and other chemical vehicles involved in accidents, various types of paints. Weapons used in burglary, arson, etc. different types of poisons and poisons and poisonous substances, hair, skeletal remains and other plant or animal remnants. Apart from these, forensic scientists are also to examine the forged signatures and documents along with the photographic analysis of all materials exhibits. Any material exhibit encountered in the way of investigation needs to be thoroughly examined to prove or disprove its association a particular crime or criminal. Practically the forensic scientist are to examine the material exhibits connected with various nature of crimes covering all sections of I. P. C. and other relevant acts and laws of the land. Unlike other research and analytical materials, forensic scientists are required to work with limited quantity and amount of materials generally left behind or carried away by criminals. For better collection of exhibits for various range of studies, forensic scientist are often summoned to the scene of crime so as to assist the investigation agencies in determining clue by means of scientific analysis. So far I have discussed about the duties and roles of forensic scientists as a whole and in general. Now I will discuss about the roll and nature of forensic scientist of different branches in connection with their respective and specialized field of work. Let us discuss first about the forensic physicist. Generally the material exhibits which are obtained at the scene of crime are examined by the scientist of this division. Besides comparative studies of various impressions and marks of tools etc.

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used in commission of crime are also made in this division. Determination of forced engine or chassis marks or restoration of an erased number upon metallic dates are also determined by the scientist of this division. Analysis of paints and glass articles, stamp impressions of forest authorities can be examined by these scientists to establish the facts for the determination of clues of commission of crimes and criminals. Secondly the scientist of forensic chemistry is also equally busy determining clues of crime and detection of criminals by their various methods of analysis. For instance it is the forensic chemist who has to determine purity of petrol, diesel and kerosene from samples. They are also to determine the quality of liquor, opium, ganja and other chemicals, analysis of explosive and the like. From their various methods of analysis, they have to establish facts basing upon which the investigating officers can detect the clues of a particular crime. Forensic biologists have also been playing an important role in examining biological exhibits oriented with crime. It is the biologist who has to analyze the biologist material exhibit starting from a micro organism to a higher plant or an animal and also their parts and products. From the skeletal remains, a biologist has to determine the sex, origin, stature, and age of the deceased. He is to identify from the skull by using superimposition method and thereby help the investigating authority in coming to a conclusion with the regard to a particular crime. In case of a suspected death case, the biologist is to ascertain the cause of death. He is also to analyze various poisonous plant materials in cases where plant poison is administered in the commission of crimes. A Serologist plays equally important role in establishing facts in respect of various crimes. In case of a murder where knife and other weapons are involved, it is the serologist who is to ascertain whether the particular weapon is stained with human blood or not. Form the findings of a serologist, the investigating officer can get a

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definite clue in a particular case, depending on which the investigating officer can identify the culprit of the crime. It is the serologist who has to establish the facts of disputed paternity cases by testing the blood group in question. Now, coming to the ballistics branch of forensic science it may be stated that a ballistic expert is the only person who ascertains whether a particular fire arm was used or not while committing a crime. He is also to examine the types of fire arms and ammunitions used in commission of a crime. He has also to establish the facts with regard to firing ranges, distance, direction, and angle of firing. After obtaining the opinion of a ballistic expert the investigating officers can come to a reasonable conclusion in respect of a particular crime. Apart from the different fire arms and ammunitions a ballistic expert is also to examine the explosive substance which is nowadays very often used for committing heinous crimes. A toxicologist determines the clues of the crime in which poison is used. In any such case, be it accidental suicidal or intentional, a toxicologist analyses the viscera and other relevant materials from which he establishes the quality and quantity of poison used. From the report of a toxicologist, the investigating officer can usually obtain vital clues for detecting the criminals involved. Similarly, the Court also gets positive evidence for coming to a conclusion in any particular case. A document expert examines the various types of documents directly or indirectly involved in a forgery case. The forgery cases may be of different types, but all these are examined by the handwriting expert. From the report of a document examiner, the investigating agency can definitely detect the real culprit of a particular case. Apart from the forged signatures or documents, a handwriting expert often gives opinion on typed papers, time of writing and the age of the ink used for writing a questionable document. So the opinion of a handwriting expert also helps the court to a conclusion in meeting the ends of justice.

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Like all others branches of science, personnel of the photography division also play a vital role in determining clues of crimes and detecting the criminals. It is the forensic photographer who establishes the connecting link of various clues of a crime by their Photographic evidence. In case of a crime where the facts of erasure are involved, it is only the photographic evidence by which the facts of easement can be established with any degree of precision. Thereby they are also helping the courts to come to a definitive opinion with regard to the case. From the above discussion it can be concluded that the forensic scientist by the very nature of his work is duty bound for the establishment of justice for the society. As a matter of fact forensic scientists are playing a vital role in reducing the potentiality of crime and also in determining the root causes of crime in our society.

3.3 Collection and Preservation of Evidence
Once the crime scene has been thoroughly documented and the locations of the evidence noted, then the collection process can begin. The collection process will usually start with the collection of the most fragile or most easily lost evidence. Special consideration can also be given to any evidence or objects which need to be moved. Collection can then continue along the crime scene trail or in some other logical manner. Photographs should also continue to be taken if the investigator is revealing layers of evidence which were not previously documented because they were hidden from sight. Most items of evidence will be collected in paper containers such as packets, envelopes, and bags. Liquid items can be transported in non-breakable, leak proof containers. Arson evidence is usually collected in air-tight, clean metal cans. Only large quantities of dry powder should be collected and stored in plastic bags. Moist or wet evidence (blood, plants, etc.) from a crime scene can be collected in plastic containers at the scene and transported back to an evidence receiving area if the

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storage time in plastic is two hours or less and this is done to prevent contamination of other evidence. Once in a secure location, wet evidence, whether packaged in plastic or paper, must be removed and allowed to completely air dry. That evidence can then be repackaged in a new, dry paper container. UNDER NO CIRCUMSTANCES SHOULD EVIDENCE CONTAINING MOISTURE BE PACKAGED IN PLASTIC OR PAPER CONTAINERS FOR MORE THAN TWO HOURS. Moisture allows the growth of microorganisms which can destroy or alter evidence. Any items which may cross contaminate each other must be packaged separately. The containers should be closed and secured to prevent the mixture of evidence during transportation. Each container should have: the collecting person's initials; the date and time it was collected; a complete description of the evidence and where it was found; and the investigating agency's name and their file number. Each type of evidence has a specific value in an investigation. The value of evidence should be kept in mind by the investigator when doing a crime scene investigation. For example, when investigating a crime he or she should spend more time on collecting good fingerprints than trying to find fibers left by a suspect's clothing. The reason is that fingerprints can positively identify a person as having been at the scene of a crime, whereas fibers could have come from anyone wearing clothes made out of the same material. Of course if obvious or numerous fibers are found at the point of entry, on a victim's body, etc., then they should be collected in case no fingerprints of value are found. It is also wise to collect more evidence at a crime scene than not to collect enough evidence. An investigator usually only has one shot at a crime scene, so the most should be made of it. The following is a breakdown of the types of evidence encountered and how the evidence should be handled:

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3.3.1 Fingerprints Fingerprints (also includes palm prints and bare footprints) are the best evidence to place an individual at the scene of a crime. Collecting fingerprints at a crime scene requires very few materials, making it ideal from a cost standpoint. All non-movable items at a crime scene should be processed at the scene using gray powder, black powder, or black magnetic powder. Polaroid 665 black and white film loaded in a Polaroid CU-5 camera with detachable flash should be used to make one-to-one photographs of prints which do not readily lift. All small transportable items should be packaged in paper bags or envelopes and sent to the crime lab for processing. Because of the "package it up and send it to the lab" mentality, some investigators skim over collecting prints at a crime scene. Collecting prints at the crime scene should be every investigator's top priority. Fingerprints from the suspect as well as elimination fingerprints from the victim will also be needed for comparison (the same holds true for palm and bare footprints). 3.3.2 Bite Marks Bite marks are found many times in sexual assaults and can be matched back to the individual who did the biting. They should be photographed using an ABFO No. 2 Scale with normal lighting conditions, side lighting, UV light, and alternate light sources. Color slide and print film as well as black and white film should be used. The more photographs under a variety of conditions, the better it is. Older bite marks which are no longer visible on the skin may sometimes be visualized and photographed using UV light and alternate light sources. If the bite mark has left an impression then maybe a cast can be made of it. Casts and photographs of the suspect's teeth and maybe the victim's teeth will be needed for comparison. For more information consult a forensic dentist.

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3.3.3 Broken Fingernails Much like a bullet that has individualizing striations on it, natural fingernails have individualizing striations on them. A broken fingernail found at a crime scene can be matched to the individual it came from many months after the crime has been committed. Broken fingernails should be placed in a paper packet which is then placed in a paper envelope. It can then be transported to the crime lab for analysis. Known samples from the suspect and maybe from the victim will be needed for comparison. 3.3.4 Questioned Documents Handwriting samples can also be matched back to the individual that produced them. Known exemplars of the suspected person's handwriting must be submitted for comparison to the unknown samples. Questioned documents can also be processed for fingerprints. All items should be collected in paper containers. For more information consult a questioned documents examiner. 3.3.5 Blood and Body Fluids If using the RFLP method of DNA analysis, then blood and seminal fluid can be matched back to an individual with a high degree of probability. Currently, if using the PCR method of DNA analysis or conventional serological techniques then blood and some body fluids can be said to come from a certain population group to which the individual belongs. As PCR technology advances, these population groups will become smaller, eventually giving it the same discriminating power as RFLP analysis has today. Dried blood and body fluid stains should be collected in the following manner: If the stained object can be transported back to the crime lab, then package it in a paper bag or envelope and send it to the lab; if the object

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cannot be transported, then either use fingerprint tape and lift it like a fingerprint and place the tape on a lift back; scrape the stain into a paper packet and package it in a paper envelope; or absorb the stain onto 1/2" long threads moistened with distilled water. The threads must be air dried before permanently packaging. For transportation purposes and to prevent cross contamination, the threads may be placed into a plastic container for no more than two hours. Once in a secure location, the threads must be removed from the plastic and allowed to air dry. They may then be repackaged into a paper packet and placed in a paper envelope. Wet blood and body fluid stains should be collected in the following manner: all items should be packaged separately to prevent cross contamination, if the item can be transported to the crime lab, then package it in a paper bag (or plastic bag if the transportation time is under two hours), bring it to a secure place and allow it to thoroughly air dry, then repackage it in a paper bag. If the item cannot be transported back to the lab, then absorb the stain onto a small (1"x1") square of pre-cleaned 100% cotton sheeting. Package it in paper (or plastic if the transportation time is less than two hours), bring it to a secure place and allow it to thoroughly air dry; then repackage it in a paper envelope. UNDER NO CIRCUMSTANCES SHOULD WET OR MOIST ITEMS REMAIN IN PLASTIC OR PAPER CONTAINERS FOR MORE THAN TWO HOURS. Victim and suspect's known whole blood samples will have to be collected in yellow, red, or purple top "Vacutainers." Contact the lab to which the samples will be submitted for specific information. 3.3.6 Firearms and Tool Marks Bullets and casings found at the crime scene can be positively matched back to a gun in the possession of a suspect. Bullets and casings can also be examined at the crime lab and sometimes tell an investigator what make and model of weapons may have expended the casing or bullet. A bullet found at

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the crime scene can sometimes be matched back to the same lot of ammunition found in a suspect's possession. Tool marks can be positively matched to a tool in the suspect's possession. Firearm safety is a must at any crime scene. If a firearm must be moved at a crime scene, never move it by placing a pencil in the barrel or inside the trigger guard. Not only is this unsafe, but it could damage potential evidence. The gun can be picked up by the textured surface on the grips without fear of placing unnecessary fingerprints on the weapon. Before picking up the gun, make sure that the gun barrel is not pointed at anyone. Keep notes on the condition of the weapon as found and stops taken to render it as safe as possible without damaging potential evidence. The firearm can then be processed for prints and finally rendered completely safe. FIREARMS MUST BE RENDERED SAFE BEFORE SUBMISSION TO THE CRIME LAB. The firearm should be packaged in an envelope or paper bag separately from the ammunition and/or magazine. The ammunition and/or magazine should be placed in a paper envelope or bag. It is important that the ammunition found in the gun be submitted to the crime lab. Any boxes of similar ammunition found in a suspect's possession should also be placed in a paper container and sent to the crime lab. Casings and/or bullets found at the crime scene should be packaged separately and placed in paper envelopes or small cardboard pillboxes. If knives (or other sharp objects) are being submitted to the lab (for tool marks, fingerprints, serology, etc.), then the blade and point should be wrapped in stiff unmovable cardboard and placed in a paper bag or envelope. The container should be labeled to warn that the contents are sharp and precautions should be taken. This is to prevent anyone from being injured. 3.3.7 Shoeprints and Tire Tracks

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Shoeprints and tire tracks can be matched positively to a pair of shoes or to tires in a suspect's possession. Shoeprints and tire tracks can sometimes tell investigators what type of shoes or tires to look for when searching a suspect's residence or vehicles. Before any attempt is made at collecting shoeprints or tire tracks, one-to-one photographs should be made using a tripod, ruler, and level. The flash should be held at about 45 degree angles from the surface containing an impression. Casts can be made of impressions using dental stone. Once hardened, the cast can be packaged in paper and submitted to the lab. When photographing prints on hard flat surfaces the flash should be used as side lighting. Shoeprints on hard flat surfaces can also sometimes be lifted like a fingerprint. Dust prints on certain surfaces can be lifted with an electrostatic dustprint lifter. 3.3.8 Fracture Matches Fracture matches can positively link broken pieces at the scene with pieces found in the possession of a suspect. For example, headlight fragments found at the scene of a hit and run could be positively matched to a broken headlight (just like putting together a jigsaw puzzle) on a suspect's vehicle. Larger fragments should be placed in paper bags or envelopes. Smaller fragments should be placed in a paper packet and then placed in an envelope.

3.3.9 Hair If a root sheath is attached, then DNA analysis using PCR technology can say that this hair came from a certain percentage of the population to which the suspect belongs. If there is no root sheath, then a microscopic analysis can say that the hair has the same characteristics as the suspect's hair and is similar to his or her hair. At this point, no one can say that a hair came from a

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particular individual. Hair found at the scene should be placed in a paper packet and then placed in an envelope. If a microscopic examination is required, then 15-20 representative hairs from the suspect must be submitted to the lab for comparison. If DNA analysis if going to be used, then a whole blood sample from the suspect must be submitted to the lab in a "Vacutainer." Contact a DNA lab for more information. 3.3.10 Fibers Fibers can be said that they are the same type and color as those found in a suspect's clothes, residence, vehicle, etc. Fibers should be collected in a paper packet and placed in an envelope. Representative fibers should be collected from a suspect and submitted to the lab for comparison. 3.3.11 Paint Paint can be said that it is the same type and color as paint found in the possession of a suspect. Paint fragments should be collected in a paper packet and placed in an envelope. Representative paint chips or samples should be collected from the suspect and submitted to the lab for comparison.

3.3.12 Glass Glass can be said that it has the same characteristics as glass found in the possession of a suspect. Smaller glass fragments should be placed in a paper packet and then in an envelope. Larger pieces should be wrapped securely in paper or cardboard and then placed in a padded cardboard box to prevent further breakage. 3.3.13 Other Trace Evidence

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Sometimes during the commission of a crime, there are other items which may be transferred to a perpetrator from the scene or from the perpetrator to the scene (sheetrock, safe insulation. etc.). The guidelines for collecting the evidence and obtaining known samples are about the same as for paint and fibers. For specific information, contact your crime lab.

Forensic Science in India
4.1 Overview
Let us first cultivate the legal aspect of forensic and medical evidence in the India. As per Section 45 of Indian evidence Act 1872- When the Court has to form and opinion upon a point of foreign law or of science or art, or as to identity of handwriting or finger impressions, the opinions upon that point of persons specially skilled in such foreign law, science or art, or in questions as to identity of handwriting or finger impressions are relevant facts. Such persons are called

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experts. Further as per Section 46 of Indian evidence Act 1872- it is stated that facts, not otherwise relevant, are relevant if they support or are inconsistent with the opinions of experts, when such opinions are relevant. Thus the ingredients of section 45 and section 46 are highlights that:

The court when necessary will place its faith on skills of persons who have technical knowledge of the facts concerned. The court will rely on the bona fide statement of proof given by the expert concluded on the basis of scientific techniques. The evidence considered irrelevant would be given relevance in eyes of law if they are consistent with the opinion of experts.



Thus we see that expert evidence helps the courts to draw logical conclusions from the facts presented by experts, which are based on their opinions derived by their specialized skills acquired by study and experience. Hence, experts are routinely involved in the administration of justice particularly in criminal cases.

4.2 Highlighting the situation in the most sought after experts:
4.2.1 The Medical Experts: In India, we have adversarial system of justice administration and ordinarily medical evidence is admitted only when the expert gives an oral evidence under oath in the courts of law expect under special circumstances like:
i. ii.

When evidence has already been admitted in a lower court; Expert opinions expressed in a treatise;

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iii. iv. v.

Evidence given in a previous judicial proceeding; Expert cannot be called as witness; Hospital records like admission/discharge register, birth/death certificates etc.

In, India, it is a common perception that lot of time and effort is required to record evidence and therefore by enlarge members of the medical profession does not like to involve in medico legal cases. Some of the possible reasons put forward for this perception are:
i. ii. iii.

Undue time consumption; Repeated adjournments; Lack of work culture in the courts

Hardly, any scientific data is available to support or refute this perception in relation to medical evidence. Therefore, it was planned to undertake a pilot study to analyze the quantum of time and effort put in by medical experts to get the evidence recorded in criminal courts and other issues related to it. 4.2.2 DNA technology in Indian legal scenario: Determination of parentage: Indian courts have time and again held that the evidence for proving nonaccess must be strong, distinct, satisfactory and conclusive. DNA tests can be strong evidence as they are correct up to 99% if positive and 100% if negative. Related case laws:
 

Vasu Vs Santha 1975 (Kerala) Gautam Kundu Vs State Of West Bengal

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In the above cases the court has laid down certain guidelines regarding DNA tests and their admissibility to prove parentage.
i. ii.

That courts in India cannot order blood test as a matter of course; Wherever applications are made for such prayers in order to have roving inquiry, the prayer for blood test cannot be entertained. There must be a strong prima facie case in that the husband must establish non-access in order to dispel the presumption arising under Section 112 of the Evidence Act.



The court must carefully examine as to what would be the consequence of ordering the blood test; whether it will have the effect of branding a child as a bastard and the mother as an unchaste woman.


No one can be compelled to give sample of blood for analysis.

Further the court said Blood-grouping test is a useful test to determine the question of disputed paternity. It can be relied upon by courts as a circumstantial evidence, which ultimately excludes a certain individual as a father of the child. However, it requires to be carefully noted no person can be compelled to give sample of blood for analysis against his/her will and no adverse inference can be drawn against him/her for this refusal. 4.2.3 Crime detection and DNA technology: Though there is no specific DNA legislation enacted in India, Sec.53 and Sec. 54 of the Criminal Procedure Code, 1973 provides for DNA tests impliedly and they are extensively used in determining complex criminal problems. Sec. 53 deals with examination of the accused by medical practitioner at the request of police officer if there are reasonable grounds to believe that an

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examination of his person will afford evidence as to the commission of the offence. Sec. 54 of the Criminal Procedure Code, 1973 further provides for the examination of the arrested person by the registered medical practitioner at the request of the arrested person. The law commission of India in its 37th report stated that to facilitate effective investigation, provision has been made authorizing an examination of arrested person by a medical practitioner, if from the nature of the alleged offence or the circumstances under which it is alleged to have been committed, there are reasonable grounds for believing that an examination of the person will afford evidence. Sec. 27(1) of Prevention of Terrorism Act, 2002 says when a investigating officer request the court of CJM or the court of CMM in writing for obtaining sample of hand writing, finger prints, foot prints, photographs, blood, saliva, semen, hair, voice of any accused person, reasonable suspect to be involved in the commission of an offence under this act. It shall be lawful for the court of CJM or the court of CMM to direct that such samples shall be given by the accused person to the police officer either through a medical practitioner or otherwise as the case may be.

4.3 Conclusion
There is a unanimity that medical and forensic evidence plays a crucial role in helping the courts of law to arrive at logical conclusions. Therefore, the expert medical professionals should be encouraged to undertake medico legal work and simultaneously the atmosphere in courts should be congenial to the medical witness. This attains utmost importance looking at the outcome of the case, since if good experts avoid court attendance, less objective professional will fill the gap, ultimately affecting the justice. The need to involve more and more professionals in

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expert testimony has been felt by different organizations. The American College of physician's guidelines for the physician expert witness emphasizes on broad physician participation in providing this much-needed assistance to the legal system. The college believes that more doctors should serve as experts as a component of their professional activities in order to meet the need for medical testimony. This objective of greater expert participation can only be achieved by addressing to the apprehensions that ponder the mind of medical professionals. In the light of new developments in the forensic science, the home ministry, Govt. of India constituted a committee under the chairmanship of Dr. Justice V.S Malimath to suggest reforms in the criminal justice system. This committee suggested comprehensive use of forensic science in crime investigation. According to the committee DNA experts should be included in the list of experts given in section 293(4) of Cr.P.C, 1973.

4.4 Suggestions provided by the Malimath Committee:

Sec. 313 of the CR.P.C must also be amended so as to draw adverse inference against the accused if he fails to answer any relevant material against him therefore, making it easy for the law enforcers to use DNA tests against him.


A specific law should be enacted giving guidelines to the police setting uniform standards for obtaining genetic information and creating adequate safeguards to prevent misuse of the same.


A national DNA database should be created which will be immensely helpful in the fight against terrorism. More well-equipped laboratories should be established to handle DNA samples and evidence. Efforts should be taken to create more awareness among general public, Prosecutors, judges and police machinery.



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4.5 Different aspects of the justice administration can be further improved by the following measures:
i. ii. iii.

Discouraging routine summoning of doctors; Calling expert witness at pre-scheduled time; Recording experts' testimony by alternative judicial officer in case of nonavailability of the presiding officer the court that summoned him. Amending provision of criminal procedures to have admissibility of the medical records; Recording of experts' testimony through video-conferencing.



5.1 Autopsy is the most Important Role of a Forensic Scientist
An autopsy—also known as a post-mortem examination, necropsy (particularly as to non-human bodies), autopsia cadaverum, or obduction—is a highly specialized surgical procedure that consists of a thorough examination of a corpse to determine the cause and manner of death and to evaluate any disease or injury that may be present. It is usually performed by a specialized medical doctor called a pathologist. Autopsies are either performed for legal or medical purposes. For example, a forensic autopsy is carried out when the cause of death may be a criminal matter, while a clinical or academic autopsy is performed to find the medical cause of death and is used in cases of unknown or uncertain death, or for research purposes. Autopsies can be further classified into cases where external examination suffices, and those where the body is dissected and internal examination is conducted. Permission from next of kin may be required for internal autopsy in some cases.

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Once an internal autopsy is complete the body is reconstituted by sewing it back together.

5.2 History of Autopsy
The term "autopsy" derives from the Ancient Greek autopsia, "to see for oneself", derived from αυτος (autos, "oneself") and όψις (opsis, "eye"). Around 3000 BC, the ancient Egyptians were one of the first civilizations to practice the removal and examination of the internal organs of humans in the religious practice of mummification. Autopsies that opened the body to determine the cause of death are attested at least in the early third millennium BC, although they were opposed in many ancient societies where it was believed that the outward disfigurement of dead persons prevented them from entering the afterlife (as with the Egyptians, who removed the organs through tiny slits in the body). Notable Greek autopsists were Erasistratus and Herophilus of Chalcedon, who lived in 3rd century BC Alexandria, but in general, autopsies were rare in ancient Greece. In 44 BC, Julius Caesar was the subject of an official autopsy after his murder by rival senators, and the physician's report noted that the second stab wound Caesar received was the fatal one. By around 150 BC, ancient Roman legal practice had established clear parameters for autopsies. The dissection of human remains for medical reasons continued to be practiced irregularly after the Romans, for instance by the Arab physicians Avenzoar and Ibn al-Nafis, but the modern autopsy process derives from the anatomists of the Renaissance. Giovanni Morgagni (1682–1771), celebrated as the father of anatomical pathology, wrote the first exhaustive work on pathology, De Sedibus et Causis Morborum per Anatomen Indagatis (The Seats and Causes of Diseases Investigated by Anatomy, 1769).

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The great nineteenth-century medical researcher Rudolf Virchow, in response to a lack of standardization of autopsy procedures, established and published specific autopsy protocols (one such protocol still bears his name).

5.3 Purpose of Autopsy
The principal aim of an autopsy is to determine the cause of death, the state of health of the person before he or she died, and whether any medical diagnosis and treatment before death was appropriate. In most Western countries the number of autopsies performed in hospitals has been decreasing every year since 1955. Critics, including pathologist and former JAMA editor George Lundberg, have charged that the reduction in autopsies is negatively affecting the care delivered in hospitals, because when mistakes result in death, they are often not investigated and lessons therefore remain unlearned. When a person has given permission in advance of their death, autopsies may also be carried out for the purposes of teaching or medical research. An autopsy is frequently performed in cases of sudden death, where a doctor is not able to write a death certificate, or when death is believed to result from an unnatural cause. These examinations are performed under a legal authority (Medical Examiner or Coroner or Procurator Fiscal) and do not require the consent of relatives of the deceased. The most extreme example is the examination of murder victims, especially when medical examiners are looking for signs of death or the murder method, such as bullet wounds and exit points, signs of strangulation, or traces of poison. Many religions such as Judaism and Islam usually discourage the performing of autopsies on their adherents. Organizations such as Zaka in Israel and Misaskim in the USA generally guide families how to ensure that an unnecessary autopsy is not made. 5.3.1 In Medicine:

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Autopsies are important in clinical medicine as they can identify medical error and assist continuous improvement. A study that focused on myocardial infarction (heart attack) as a cause of death found significant errors of omission and commission, i.e. a sizable number cases ascribed to myocardial infarctions (MIs) were not MIs and a significant number of non-MIs were actually MIs. A large meta-analysis suggested that approximately one-third of death certificates are incorrect and that half of the autopsies performed produced findings that were not suspected before the person died. Also, it is thought that over one fifth of unexpected findings can only be diagnosed histological, i.e. by biopsy or autopsy, and that approximately one quarter of unexpected findings, or 5% of all findings, are major and can similarly only be diagnosed from tissue. One study found that "Autopsies revealed 171 missed diagnoses, including 21 cancers, 12 strokes, 11 myocardial infarctions, 10 pulmonary emboli, and 9 endocarditic, among others". Focusing incubated patients, one study found "abdominal pathologic conditions--abscesses, bowel perforations, or infarction--were as frequent as pulmonary emboli as a cause of class I errors. While patients with abdominal pathologic conditions generally complained of abdominal pain, results of examination of the abdomen were considered unremarkable in most patients, and the symptom was not pursued".

5.4 Types of Autopsy
There are three main types of autopsies:

Medico-Legal Autopsies or Forensic or coroner's autopsies seek to find the cause and manner of death and to identify the decedent. They are generally

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performed, as prescribed by applicable law, in cases of violent, suspicious or sudden deaths, deaths without medical assistance or during surgical procedures.

Clinical or Pathological autopsies are performed to diagnose a particular disease or for research purposes. They aim to determine, clarify, or confirm medical diagnoses that remained unknown or unclear prior to the patient's death.


Anatomical or academic autopsies are performed by students of anatomy for study purpose only.

5.5 Forensic Autopsy:
Autopsy room of the Charité BerlinA forensic autopsy is used to determine the cause of death. Forensic science involves the application of the sciences to answer questions of interest to the legal system. In United States law, deaths are placed in one of five manners:  Natural  Accident  Homicide  Suicide  Undetermined In some jurisdictions, the Undetermined category may include deaths in absentia, such as deaths at sea and missing persons declared dead in a court of law; in others, such deaths are classified under "Other". But, medical examiners also attempt to determine the time of death, the exact cause of death, and what, if anything, preceded the death, such as a struggle. A forensic autopsy may include obtaining

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biological specimens from the deceased for toxicological testing, including stomach contents. Toxicology tests may reveal the presence of one or more chemical "poisons" (all chemicals, in sufficient quantities, can be classified as a poison) and, the quantity of those chemicals. Because post-mortem deterioration of the body, together with the gravitational pooling of bodily fluids, will necessarily alter the bodily environment, toxicology tests may overestimate, rather than underestimate, the quantity of the suspected chemical. Most states require the State medical examiner to complete an autopsy report and many mandate that the autopsy be videotaped. Following an in-depth examination of all the evidence, a medical examiner or coroner will assign a manner of death as one of the five listed above, and detail the evidence on the mechanism of the death.

5.6 Clinical Autopsy:
Clinical autopsies serve two major purposes. They are performed to gain more insight into pathological processes and determine what factors contributed to a patient's death. Autopsies are also performed to ensure the standard of care at hospitals. Autopsies can yield insight into how patient deaths can be prevented in the future. Within the United Kingdom, clinical autopsies can only be carried out with the consent of the family of the deceased person as opposed to a medico-legal autopsy instructed by a Coroner (England & Wales) or Procurator Fiscal (Scotland) to whom the family cannot object.

5.7 Process of Autopsy
Similar to those used in medical or forensic autopsies. The body is received at a medical examiner's office or hospital in a body bag or evidence sheet. A new body

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bag is used for each body to ensure that only evidence from that body is contained within the bag. Evidence sheets are an alternate way to transport the body. An evidence sheet is a sterile sheet that the body is covered in when it is moved. If it is believed there may be any significant residue on the hands, for instance gunpowder, a separate paper sack is put around each hand and taped shut around the wrist. There are two parts to the physical examination of the body: the external and internal examination. Toxicology, biochemical tests and/or genetic testing often supplement these and frequently assist the pathologist in assigning the cause or causes of death. 5.7.1 External Examination: At many institutions the person responsible for handling, cleaning, and moving the body is often called a diener, the German word for servant. In the UK this role is performed by an Anatomical Pathology Technologist who will also assist the pathologist in eviscerating the deceased and reconstruction after the autopsy. After the body is received, it is first photographed. The examiner then notes the kind of clothes and their position on the body before they are removed. Next, any evidence such as residue, flakes of paint or other material is collected from the external surfaces of the body. Ultraviolet light may also be used to search body surfaces for any evidence not easily visible to the naked eye. Samples of hair, nails and the like are taken, and the body may also be radio graphically imaged. Once the external evidence is collected, the body is removed from the bag, undressed, and any wounds present are examined. The body is then cleaned, weighed, and measured in preparation for the internal examination. The scale used to weigh the body is often designed to accommodate the cart that the body is transported on; its weight is then deducted from the total weight shown to give the weight of the body.

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If not already within an autopsy room, the body is transported to one and placed on a table. A general description of the body as regards ethnicity, sex, age, hair color and length, eye color and other distinguishing features (birthmarks, old scar tissue, moles, etc.) is then made. A handheld voice recorder or a standard examination form is normally used to record this information. In some countries e.g. France, Germany, and Canada, an autopsy may comprise an external examination only. This concept is sometimes termed a "view and grant". The principles behind this being that the medical records, history of the deceased and circumstances of death have all indicated as to the cause and manner of death without the need for an internal examination.[citation needed] 5.7.2 Internal Examination If not already in place, a plastic or rubber brick called a "body block" is placed under the back of the body, causing the arms and neck to fall backward whilst stretching and pushing the chest upward to make it easier to cut open. This gives the prosector, a pathologist or assistant, maximum exposure to the trunk. After this is done, the internal examination begins. The internal examination consists of inspecting the internal organs of the body for evidence of trauma or other indications of the cause of death. For the internal examination there are a number of different approaches available:

A large and deep Y-shaped incision can be made

starting at the top of each shoulder and running down the front of the chest, meeting at the lower point of the sternum. This is the approach most often used.

A T-shaped incision made from the tips of both

shoulder, in a horizontal line across the region of the collar bones to meet at the sternum (breastbone) in the middle.

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A single vertical cut is made from the middle of the

neck (in the region of the 'adam's apple' on a male body) In all of the above cases the cut then extends all the way down to the pubic bone (making a deviation to the left side of the navel). Bleeding from the cuts is minimal, or non-existent, because the pull of gravity is producing the only blood pressure at this point, related directly to the complete lack of cardiac functionality. However, in certain cases there is anecdotal evidence to prove that bleeding can be quite profuse, especially in cases of drowning. At this point, shears are used to open the chest cavity. It is also possible to utilize a simple scalpel blade. The prosector uses the tool to saw through the ribs on the lateral sides of the chest cavity to allow the sternum and attached ribs to be lifted as one chest plate; this is done so that the heart and lungs can be seen in situ and that the heart, in particular the pericardial sac is not damaged or disturbed from opening. A scalpel is used to remove any soft tissue that is still attached to the posterior side of the chest plate. Now the lungs and the heart are exposed. The chest plate is set aside and will be eventually replaced at the end of the autopsy. At this stage the organs are exposed. Usually, the organs are removed in a systematic fashion. Making a decision as to what order the organs are to be removed will depend highly on the case in question. Organs can be removed in several ways: The first is the en masse technique of letulle whereby all the organs are removed as one large mass. The second is the en bloc method of Ghon. The most popular in the UK is a modified version of this method which is divided into four groups of organs. Although these are the two predominant evisceration techniques in the UK variations on these are widespread.

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One method is described here: The pericardial sac is opened to view the heart. Blood for chemical analysis may be removed from the inferior vena cava or the pulmonary veins. Before removing the heart, the pulmonary artery is opened in order to search for a blood clot. The heart can then be removed by cutting the inferior vena cava, the pulmonary veins, the aorta and pulmonary artery, and the superior vena cava. This method leaves the aortic arch intact, which will make things easier for the embalmer. The left lung is then easily accessible and can be removed by cutting the bronchus, artery, and vein at the hilum. The right lung can then be similarly removed. The abdominal organs can be removed one by one after first examining their relationships and vessels. Some pathologists, however, prefer to remove the organs all in one "block". Then a series of cuts, along the vertebral column, are made so that the organs can be detached and pulled out in one piece for further inspection and sampling. During autopsies of infants, this method is used almost all of the time. The various organs are examined, weighed and tissue samples in the form of slices are taken. Even major blood vessels are cut open and inspected at this stage. Next the stomach and intestinal contents are examined and weighed. This could be useful to find the cause and time of death, due to the natural passage of food through the bowel during digestion. The more area empty, the longer the deceased had gone without a meal before death. The body block that was used earlier to elevate the chest cavity is now used to elevate the head. To examine the brain, an incision is made from behind one ear, over the crown of the head, to a point behind the other ear. When the autopsy is completed, the incision can be neatly sewn up and is not noticed when the head is resting on a pillow in an open casket funeral. The scalp is pulled away from the skull in two flaps with the front flap going over the face and the rear flap over the back of the neck. The skull is then cut with

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what is called a Stryker saw, named for its manufacture, to create a "cap" that can be pulled off, exposing the brain. The brain is then observed in situ. Then the brain's connection to the cranial nerves and spinal cord are severed, and the brain is then lifted out of the skull for further examination. If the brain needs to be preserved before being inspected, it is contained in a large container of formalin (15 percent solution of formaldehyde gas in buffered water) for at least two but preferably four weeks. This not only preserves the brain, but also makes it firmer allowing easier handling without corrupting the tissue. 5.7.3 Reconstitution of the Body: An important component of the autopsy is the reconstitution of the body such that it can be viewed, if desired, by relatives of the deceased following the procedure. After the examination, the body has an open and empty chest cavity with chest flaps open on both sides, the top of the skull is missing, and the skull flaps are pulled over the face and neck. It is unusual to examine the face, arms, hands or legs internally. In the UK, following the Human Tissue Act 2004 all organs and tissue must be returned to the body unless permission is given by the family to retain any tissue for further investigation. Normally the internal body cavity is lined with cotton wool or an appropriate material; the organs are then placed into a plastic bag to prevent leakage and returned to the body cavity. The chest flaps are then closed and sewn back together and the skull cap is sewed back in place. Then the body may be wrapped in a shroud and it is common for relatives of the deceased to not be able to tell the procedure has been done when the deceased is viewed in a funeral parlor after embalming.

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