Forensic science

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Forensic science
Physiological sciences
Forensic pathology · Forensic dentistry
Forensic anthropology · Forensic entomology · Forensic archaeology
Social sciences
Forensic psychology · Forensic psychiatry
Other specializations
Fingerprint analysis · Forensic accounting
Ballistics  · Bloodstain pattern analysis  · Body identification
DNA profiling · Forensic arts · Forensic toxicology
Forensic footwear evidence
Questioned document examination
Cybertechnology in forensics
Information forensics · Computer forensics
Related disciplines
Forensic engineering
Forensic materials engineering
Forensic polymer engineering
Fire investigation
Vehicular accident reconstruction
People in Forensics
Auguste Ambroise Tardieu
Edmond Locard
Bill Bass
Related articles
Crime scene · CSI Effect
Trace evidence · Skid mark
Use of DNA in forensic entomology

Forensic science (often shortened to forensics) is the application of a broad spectrum of sciences to answer questions of interest to the legal system.This may be in relation to a crime or to a civil action. But besides its relevance to the underlying legal system, more generally forensics encompasses the accepted scholarly or scientific methodology and norms under which the facts regarding an event, or an artifact, or some other physical item (such as a corpse, or cadaver, for example) are to the broader notion of authentication whereby an interest outside of a legal form exists in determining whether an object is in fact what it purports to be, or is alleged as being.

The word “forensic” comes from the Latin adjective “forensis” meaning of or before the forum. During the time of the Romans, 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 side of the story. The individual with the best argument and delivery would determine the outcome of the case. Basically, the person with the sharpest forensic skills would win. 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 place of "forensic science" can be considered incorrect 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".

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[edit] History of forensic science

The "Eureka" legend of Archimedes (287-212 BC) can be considered an early use of forensic anthropology. He determined that a crown was not completely made up of gold (as it was fraudulently claimed). This conclusion was reached by evaluating the density of the object using measurements of its displacement and its weight, as he was not allowed to damage the crown.The earliest account of fingerprint use to establish identity was during the 7th century. According to an Arabic merchant, Soleiman, a debtor's fingerprints were affixed to a bill, which would then be given to the lender. This bill was legally recognized as proof of the validity of the debt.[citation needed]

The first written account of using medicine and entomology to solve (separate) criminal cases is attributed to the book Xi Yuan Ji Lu (洗冤集錄, translated as "Collected Cases of Injustice Rectified"), written in Song Dynasty China by Song Ci (宋慈, 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. 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]

In sixteenth 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 which occurred in the structure of the body as the result of disease. In the late 1700s, 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, 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 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, England, 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, England, 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.[2] Later in the 20th century, several British pathologists, Bernard Spilsbury, Francis Camps, Sydney Smith and Keith Simpson would pioneer new forensic methods in Britain.

[edit] Subdivisions of forensic science

Agents of the United States Army Criminal Investigation Division investigate a crime scene
  • Computational forensics concerns the development of algorithms and software to assist forensic examination.
  • Criminalistics is the application of various sciences to answer questions relating to examination and comparison of biological evidence, trace evidence, impression evidence (such as fingerprints, footwear impressions, and tire tracks), controlled substances, ballistics, firearm and toolmark examination, and other evidence in criminal investigations. Typically, evidence is processed in a crime lab.
  • Digital forensics is the application of proven scientific methods and techniques in order to recover data from electronic / digital media. Digital Forensic specialists work in the field as well as in the lab (see Data recovery).
  • Forensic anthropology is the application of physical anthropology in a legal setting, usually for the recovery and identification of skeletonized human remains.
  • Forensic archaeology is the application of a combination of archaeological techniques and forensic science, typically in law enforcement.
  • Forensic DNA analysis takes advantage of the uniqueness of an individual's DNA to answer forensic questions such as determining paternity/maternity or placing a suspect at a crime scene.
  • Forensic entomology deals with the examination of insects in, on, and around human remains to assist in determination of time or location of death. It is also possible to determine if the body was moved after death.
  • Forensic geology deals with trace evidence in the form of soils, minerals and petroleums.
  • Forensic interviewing is a method of communicating designed to elicit information and evidence.
  • Forensic meteorology is a site specific analysis of past weather conditions for a point of loss.
  • Forensic odontology is the study of the uniqueness of dentition better known as the study of teeth.
  • Forensic pathology is a field in which the principles of medicine and pathology are applied to determine a cause of death or injury in the context of a legal inquiry.
  • Forensic psychology is the study of the mind of an individual, using forensic methods. Usually it determines the circumstances behind a criminal's behavior.
  • Forensic toxicology is the study of the effect of drugs and poisons on/in the human body.
  • Forensic document examination or questioned document examination answers questions about a disputed document using a variety of scientific processes and methods. Many examinations involve a comparison of the questioned document, or components of the document, to a set of known standards. The most common type of examination involves handwriting wherein the examiner tries to address concerns about potential authorship.
  • Veterinary Forensics is forensics applied to crimes involving animals.

[edit] Questionable forensic techniques

Some forensic techniques, believed to be scientifically sound at the time they were used, have turned out later to have much less scientific merit, or none. Some such techniques include:

  • Comparative bullet-lead analysis was used by the FBI for over four decades, starting with the John F. Kennedy assassination in 1963. The theory was that each batch of ammunition possessed a chemical makeup so distinct that a bullet could be traced back to a particular batch, or even a specific box. However, internal studies and an outside study by the National Academy of Sciences found that the technique was unreliable, and the FBI abandoned the test in 2005.[3]
  • Forensic dentistry has come under fire; in at least two cases, bite mark evidence has been used to convict people of murder who were later freed by DNA evidence. A 1999 study by a member of the American Board of Forensic Odontology found a 63 percent rate of false identifications and is commonly referenced within online news stories and conspiracy websites.[4][5] However, the study was based on an informal workshop during an ABFO meeting which many members did not consider a valid scientific setting. [6]

[edit] Litigation science

Litigation science describes analysis or data developed or produced expressly for use in a trial, versus those produced in the course of independent research. This distinction was made by the U.S. 9th Circuit Court of Appeals when evaluating the admissibility of experts.[7]

This uses demonstrative evidence, which is evidence created in preparation of trial by attorneys or paralegals.

[edit] Forensic science in fiction

Sherlock Holmes, the fictional character created by Sir Arthur Conan Doyle in works produced from 1887 to 1915, used forensic science as one of his investigating methods. Conan Doyle credited the inspiration for Holmes on his teacher at the medical school of the University of Edinburgh, the gifted surgeon and forensic detective Joseph Bell.

Decades later, the comic strip Dick Tracy also featured a detective using a considerable number of forensic methods, although sometimes the methods were more fanciful than actually possible.

Defense attorney Perry Mason occasionally used forensic techniques, both in the novels and television series.

Popular television series focusing on crime detection, including CSI, Cold Case, Bones, Law & Order, NCIS, Criminal Minds, Silent Witness, Dexter, and Waking the Dead, depict glamorized versions of the activities of 21st century forensic scientists. These related TV shows have changed individuals' expectations of forensic science, an influence termed the "CSI effect".[citation needed]

[edit] Forensic science being challenged

Questions about forensic science, fingerprint evidence and the assumption behind these disciplines have been brought to light in some publications,[8] [9] the latest being an article in the New York Post.[10] The article stated that "No one has proved even the basic assumption: That everyone's fingerprint is unique."[10] The article also stated that "Now such assumptions are being questioned -- and with it may come a radical change in how forensic science is used by police departments and prosecutors."[10]

[edit] See also

[edit] References

  1. ^ Gernet, Jacques (1962). Daily Life in China on the Eve of the Mongol Invasion, 1250-1276. Stanford: Stanford University Press. ISBN 0-8047-0720-0. 
  2. ^ Kind S, Overman M (1972). Science Against Crime. New York: Doubleday. pp. 12–13. ISBN 0-385-09249-0. 
  3. ^ Solomon, John (2007-11-18). "FBI's Forensic Test Full of Holes". The Washington Post: p. A1. http://www.washingtonpost.com/wp-dyn/content/article/2007/11/17/AR2007111701681.html. Retrieved on 2008-03-05. 
  4. ^ Santos, Fernanda (2007-01-28). "Evidence From Bite Marks, It Turns Out, Is Not So Elementary". The New York Times. http://www.nytimes.com/2007/01/28/weekinreview/28santos.html. Retrieved on 2008-03-05. 
  5. ^ McRoberts, Flynn (2004-11-29). "Bite-mark verdict faces new scrutiny". Chicago Tribune. http://www.chicagotribune.com/news/specials/chi-0411290148nov29,1,2796064.story. Retrieved on 2008-03-05. 
  6. ^ McRoberts, Flynn (2004-10-19). "From the start, a faulty science". Chicago Tribune. http://www.baltimoresun.com/news/specials/chi-041019forensics,0,4915311.story?page=6. Retrieved on 2008-07-13. 
  7. ^ Raloff, Janet (2008-01-19). "Judging Science". Science News: pp. 42 (Vol. 173, No. 3). http://www.sciencenews.org/articles/20080119/bob10.asp. Retrieved on 2008-03-05. 
  8. ^ "'Badly Fragmented' Forensic Science System Needs Overhaul". The National Academies. February 18, 2009. http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=12589. Retrieved on 2009-03-09. 
  9. ^ "National Academy of Sciences Finds 'Serious Deficiencies' in Nation's Crime Labs". National Association of Criminal Defense Lawyers. February 18, 2009. http://www.nacdl.org/public.nsf/newsreleases/2009mn06?OpenDocument. Retrieved on 2009-03-07. 
  10. ^ a b c Katherine Ramsland (Sunday, March 6, 2009). "CSI: Without a clue; A new report forces Police and Judges to rethink forensic science". The New York Post, PostScript. http://www.nypost.com/seven/03072009/postopinion/opedcolumnists/csi__without_a_clue_158464.htm. Retrieved on 2009-03-07. 

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