Fingerprints

Fingerprinting



A fingerprint is a patterned impression left by friction ridges and furrows of a human finger. The collection of fingerprints from a crime scene is a significant method of forensic science. Since no two people have exactly the same pattern, fingerprints can be used as a key identification tool. Besides identifying criminals, fingerprint analysis is used for biometric security, background checks and identifying the deceased after a natural disaster. Fingerprinting was developed in the early 20th century and now days is usually used in absence of DNA samples since fingerprint analysis is only useful if the perpetrator's print is already on file to compare with.

Types:

__Exemplar-__ Exemplar fingerprints are ones that were deliberately retrieved from the suspect, usually when under arrest or when required to be entered into a system. They are taken by using ink on paper or electronically through Live Scan. For criminal purposes, an exemplar print from each finger will be taken. __Latent-__ Latent prints refer to any fingerprints that are accidentally left and are usually invisible to the human eye as they are formed by body oils. These prints require electronic, chemical and/or physical processing in order to be visible. Latent prints are commonly distorted, overlapped or smudged so they can be difficult to use for identifying perpetrators. __Patent-__ Similar to latent prints, patent fingerprints are accidental however, they are visible to the human eye. They are caused by an outside material such as ink, dirt, and blood. Patent prints are collected through photography. __ Plastic- __ Although uncommon in the forensic field, plastic fingerprints are impressions left on soft surfaces that do not return to their original shape and therefore create a perfect mould.

History:

Fingerprints offer an infallible means of personal identification. This is the key explanation for fingerprints, which has replaced other methods of establishing the identities of criminals who are reluctant to come forth admitting previous offences. Though visible human characteristics tend to change, fingerprints are significantly persistent. Barring injuries, surgery causing deep scarring, or diseases such as leprosy, which damage the layers of friction ridge skin (injuries, scarring and diseases tend to exhibit obvious signs of unnatural change), finger and palm print features have never been shown to move about or change throughout the life of a person. Fingerprints weren't used as a method for identifying criminals until the 19th century. In 1858, an Englishman named Sir William Herschel, was working as the Chief Magistrate of the Hooghly district in Jungipoor, India. In order to reduce fraud, he had the residents record their fingerprints when signing business documents. In earlier civilizations, branding and at times maiming was used to mark the criminal for what he or she was/had done. The thief was deprived of the hand which committed the thievery. Ancient Romans executed the tattoo needle to identif y and prevent desertion of mercenary soldiers from their ranks. Before the mid ­1800's, law enforcement officers with extraordinary visual memories, dubbed "camera eyes," identified previously arrested offenders by their sight alone. Photography lessened the burden on memory, but was not the answer to the criminal identification problem. Personal appearances was easily manipulated and changed. Around 1870, French anthropologist Alphonse Bertillon constructed a system to measure and record the dimensions of certain bony parts of the body. These measurements were reduced to a formula which, would apply only to one person and would not change during his/her adult life. In 1905 the U.S army began using fingerprints and genetic identification, following by the U.S. Navy in 1907. As of January 2015, the Unique Identification Authority of India operates the world's largest fingerprint (multi­modal biometric) system, with over 734 million (73.4 crore) fingerprint, face and iris biometric records.

How It's Done:

First, the prints are collected through a variety of methods. The most common type of prints, latent fingerprints, are stereotypically collected by dusting the smooth surface with a powder of black granular, aluminum flake or black magnetic. Then the now visible prints are photographed next to a forensic measurement scale and lifted and placed onto a card. However, this method is very susceptible to contamination so other methods such as an alternate light source (ALS), cyanoacrylate and chemicals are used. Using an alternate light source is becoming a more common method for investigators. They use laser or LED devices that emit a specific wavelength. A variety of spectra are produced and the prints are now able to be photographed or further processed with the use of powders or dyes. Cyanocrylate is a superglue that is used for processing prior to the use of powders or dyes. The non porous surface is exposed to cyanoacrylate vapours that stick to any prints present. This allows the prints to be viewed with oblique ambient light. To reveal latent prints on porous surfaces such as paper, chemicals like ninhydrin are used. Ninhydrin reacts with specific components of the latent print and causes them to turn purple. Another common chemical developer, 1,2-diazafluoren-9-one (DFO) causes fingerprints to glow when exposed to a blue-green light. From there, the prints are analyzed, compared, evaluated and verified. Computers use algorithms to match patterns and databases such as the FBI's Integrated Automated Fingerprint Identification System are used. The system holds more than 72 million prints.



Education and Career:

A fingerprint technician is a type of forensic laboratory analyst who processes and examines fingerprint evidence in criminal investigations. A position as a fingerprint technician usually requires a 4-year degree, job training, experience and professional certification. fingerprint technician works to reconstruct the circumstances and events surrounding a crime scene, with the ultimate goal of uncovering the truth, based on evidence. This involves collecting, examining, analyzing and comparing partial or latent fingerprint evidence to identify suspects and victims in criminal cases. At a crime scene, in the morgue or in the laboratory, a fingerprint technician uses various techniques to collect fingerprint evidence and will receive fingerprint cards and records for comparison and examination. This occupation requires a bachelor's degree in a natural science or forensic science and significant job training to attain a position in a crime laboratory. Bachelor's degree programs in forensic science combine multi-disciplinary science coursework in chemistry, biology, physics and statistics with forensic science and criminal justice. Extensive laboratory work and internships with local crime laboratories or other agencies serve a vital role in providing students with hands-on technical expertise. The salary ranges from fifty thousand up to seventy thousand and possibly higher depending on the field and area. Common bachelor programs chosen by individuals interested in a career in fingerprint analysis include:
 * 1) Bachelor of Arts in Social and Criminal Justice, Forensics
 * 2) Bachelor of Science in Criminal Justice, Forensics
 * 3) Bachelor of Science in Biological Sciences
 * 4) Bachelor of Science in Forensic Science

State v. Jennings:

On September 19, 1910, Clarence Hiller was shot and killed in his house by an intruder. The railing in the house was recently painted and four fingerprints were found. Thomas Jennings was found in the area and when questioned gave conflicting answers. He was searched and a loaded revolver was found. He was immediately arrested and since he had a criminal record his fingerprints were on file. The prints were compared and at the trial, four fingerprint experts testified that the pints were a conclusive match. Jennings was sentenced to death for murder on February 1, 1911. Shortly after this case, the use of fingerprint analysis became more popular across America. This case also set a precedent that fingerprint evidence was admissible in court.

Bibliography: http://murderpedia.org/male.J/j/jenning-thomas.htm http://www.forensicsciencesimplified.org/prints/ http://fingerprintinggsc.weebly.com/ Daluz, Hillary Moses. //Fundamentals of Fingerprint Analysis//. N.p.: n.p., n.d. Print.

By: Janine & Emma