Forensic Science, also known as Forensics, is the application of science to law. It uses highly developed technology to uncover scientific evidence in a variety of fields. Modern forensic science has a broad range of applications. It is used in civil cases such as forgeries, fraud or negligence. The most common use of forensic science is to investigate criminal cases involving a victim, such as assault, robbery, kidnapping , rape, or murder.
Forensic science is also used in monitoring the compliance of various countries with such international agreements as the Nuclear Non-Proliferation Treaty and the Chemical Weapons Convention and to learn whether a country is developing a secret nuclear weapons program. It can help law enforcement officials determine whether any laws or regulations have been violated in the marketing of foods and drinks, the manufacture of medicines, or the use of pesticides on crops. It can also determine whether drinking water meets legal The medical examiner is the most important individual in an investigation of a crime involving a victim.
It is the responsibility of the medical examiner to visit the crime scene, conduct an autopsy (examination f the body) in cases of death, examine the medical evidence and lab reports, study the victims history, and put all the information together in a report to be Medical examiners are usually physicians specializing in forensic pathology, the study of structural and functional changes in the body as a result of injury. Their training and qualifications most often include a medical degree and an apprenticeship in a medical examiners office. In the field of forensic science, there are many subspecialties.
They include odontology (the study of teeth), anthropology(the study of human eings), psychiatry, biology, chemistry, physics, toxicology (the study of poisons), and pathology (the examination of body tissues and fluids). The medical examiner may call upon forensic scientists who are specialized in these fields for help in a crime investigation. Toxicology is a branch of forensic science that deals with the adverse effects of drugs and poisonous chemicals found in the home, at work or in the environment. All drugs have toxic effect but the effect is most often minor.
The toxic effect of drugs may produce only a little discomfort or they may be serious enough to cause death. One of the most common cases of death by Pathology is the branch of forensic science that determines the nature and course of diseases by analyzing body fluids and tissues. Pathology is divided into clinical and anatomic pathology. Clinical pathologists contribute to the diagnosis of diseases by measuring chemicals and cells in blood, sputum, bone marrow and urine. Anatomic pathologists perform autopsies and analyze tissues taken from patients during surgery or by biopsy.
The medical examiner investigates many different types of violent crime to determine whether a violent death was an accident, a suicide, or a omicide. In cases involving gunshot wounds, the medical examiner looks for gunpowder residues on the clothing of the victim and around wounds. The information is used to determine whether the gun was fired by the victim of In the case of knife wounds, the medical examiner must distinguish between a cut (an injury that is longer than deep) and a stab wound (an injury that is deeper than long).
He must also be able to identify a defense wound which is a cut caused when a victim grabs the knife in self-defense. Cuts are associated with suicide. The body of the victim usually has numerous parallel uts which indicate hesitant wounds or repeated hesitant trials before the final cut is made. Homicides typically consist of one deep gash. Medical examiners are also called upon to investigate cases of asphyxiation or death form lack of oxygen in the blood. Asphyxiation may be caused in a number of different ways, such as hanging , which can be an accident, homicide or suicide, or strangling which is homicide.
Damage to the victims air passage by an object in the throat or compression of a victims chest by a person or an objector the replacement of oxygen in the red blood ells by another gas such as carbon monoxide poisoning. That too can be a result of an accident, homicide or suicide. In a death involving carbon monoxide poisoning a closed garage door and no marks on the body are usually taken as an indication of suicide. The presence of tools around the car and grease on the victims hands is an indication of an accidental death.
The presence of a wound caused by a blow to the head or if there is no carbon monoxide in the blood of he victim indicates a homicide that was made to look like a suicide. Forensic science uses sophisticated lab techniques to detect the resence of substances in the victim, the suspected criminal, or at the crime scene. In determining whether alcohol was involved in a crime, the amount of alcohol in the blood can be measured in two ways. The first is to measure the amount of alcohol exhaled in the breath of the person. This reveals the concentration of alcohol in the person’s blood.
Blood alcohol level can also be determined by blood tests, usually through chromatography. In this method, the blood sample is vaporized by high temperature, and the gas is sent through a column that separates the different chemical compounds present in the blood. Gas chromatology also detects the presence of barbiturates, cocaine, amphetamines, and heroin. When a body is discovered in a lake, stream, river or ocean, and the lungs are filled with water, the medical examiner must determine if the drowning occurred where the body was found or somewhere else.
A standard microscope that can magnify objects to 1500 times their size is used to look for diatoms. Diatoms are single cell algae that are found in all natural bodies of water. If there are no diatoms, it can be concluded that the drowning took place in a bathtub or sink since diatoms are filtered from tap A scanning electron microscope that can magnify objects 100,000 times is used to detect tiny gunpowder particles present on he hand of a One of the oldest techniques of forensic science is dusting the scene of a crime for fingerprints.
In one method of obtaining a fingerprint, a technician spreads fine powder over a surface with a brush or magnetic wand. The powder sticks o proteins secreted by the sweat glands on the skin ridges of the fingertip When the excess powder is removed, an outline of the contours of the ridges remains. The print may also be chemically treated to reveal the ontours. Since no two fingerprints are the same, fingerprinting is a positive Other evidence that may be found at a crime scene is blood, hair, skin, or semen. Human bite marks can also serve as evidence.
Bites can be found on the victims body or in pieces of food or gum found at the crime scene. A forensic scientist can fill the impression caused by the bite marks with a liquid plastic. The cast will form an accurate replica of the assailants teeth which is then compared with a cast of the suspects teeth. District attorneys call forensic scientists to give their expert testimony n a trial concerning what they find from an autopsy and what they write in the lab reports. Expert testimony is the statement given by a specialist who has been recognized as having expert knowledge about evidence in the case.
An expert witness is allowed to give an opinion about whether or not the evidence is valid. An expert witness may also quote the statements of other experts to support an opinion. Ordinary witnesses are restricted to giving statements about what they actually saw or heard. The medical and legal approach to dealing with crimes began in England during the 12th century. King Richard I established the Office of the Coroner. The coroners main job was to keep a record of all criminal affairs in the county and investigate all deaths that were believed to be a homicide or suicide.
The need for more scientific investigation of unnatural deaths became evident and the coroners began asking doctors for help. Over time medical schools started to prepare doctors in that specific field. In 1807, the University of Edinburgh in Scotland instituted a Department of Legal Early American colonists Bought the coroner system with them. As medical involvement in investigating violent and unexplained deaths increased, communities began requiring that coroners have specific academic training.
In 1877, Massachusetts replaced the coroners office with the Office of the Medical Examiner, which was to be headed by a physician. Soon many other states followed. In 1915 New York City established a program where the medical examiner was authorized to investigate all deaths that occurred to people who appeared to be in good health, that resulted from criminal Computer technology now allows law enforcement officers o record ingerprints digitally and to transmit and receive information for quick identification.
Recent developments in technology allows scientists o examine the deoxyribonucleic acid (DNA) or genetic material of blood, hair, skin, or semen to see if they belong to the victim or the suspected criminal. Using polymerase chain reaction (PCR), a lab can clone the DNA from a very small Forensic science as practiced today is a field of science medicine that uses electron microscopes, lasers, ultraviolet and infrared light, advanced chemical techniques and computerized databanks to analyze and research evidence.