Forensic crime investigation the role of dna prof henri fouche unisa
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FORENSIC CRIME INVESTIGATION: THE ROLE OF DNA Prof Henri Fouche UNISA. CAMPROSA CONFERENCE 08 – 11 NOVEMBER 2011 On board M.S.C. SINFONIA. INVESTIGATION.

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FORENSIC CRIME INVESTIGATION: THE ROLE OF DNA Prof Henri Fouche UNISA

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Forensic crime investigation the role of dna prof henri fouche unisa

FORENSIC CRIME INVESTIGATION: THE ROLE OF DNAProf Henri FoucheUNISA

CAMPROSA CONFERENCE

08 – 11 NOVEMBER 2011

On board M.S.C. SINFONIA

camprosa conference 8 - 11 November 2011


Investigation

INVESTIGATION

  • CRIMINAL INVESTIGATION is the quest for information that can be used as court evidence to secure the conviction of one or several suspects (LemanLanglois,2008:191)

  • FORENSIC INVESTIGATION is an investigation aimed at instituting court proceedings and where some or other scientific knowledge is applied to a legal problem (Lamprecht 2001:93)

camprosa conference 8 - 11 November 2011


Purpose of an investigation

PURPOSE OF AN INVESTIGATION

  • to establish whether an act may be labelled a crime

  • The collection of evidence to determine who is responsible and how they will be dealt with by the criminal justice system (Clark,2004:5-6)

    AN INVESTIGATION SHOULD BE ABLE TO ESTABLISH

  • The date, time and place where the crime occurred

  • The identity of the individuals involved in the planning, execution and after-effect of the misdemeanour

  • Whether there are witnesses present

  • If there is evidence of the criminal offence

  • The method of operation used to perpetrate the crime

  • If there is an indication of guilt or innocence to aid prosecuting authorities

    (Gilbert,2010:34)

camprosa conference 8 - 11 November 2011


Collecting evidence

COLLECTING EVIDENCE

  • all crime scenes, to a variable degree, contain physical evidence that may be visible to the naked eyes or so small that it can only be detected by a microscope

  • physical evidence comprises of all objects and material found in connection with an investigation that are instrumental in discovering the facts

  • the investigator should always be able to find evidence at the crime scene, linking the perpetrators to the crime scene and possibly connecting them to the elements of the crime

    (Gilbert,2010:80); (Saferstein,2004:5)

camprosa conference 8 - 11 November 2011


Locard sprinciple of exchange

LOCARD’SPRINCIPLE OF EXCHANGE

  • Edmond locard, founder of the Institute of Criminalistics in Lyon, France, believed that suspects introduce items of evidence into the crime scene and remove items with them on leaving the scene

  • This exchange of trace elements involves items such as hairs, fibres, dirt, dust, blood, body fluids, skin cells and other materials

    Source: Criminal Investigation, 2010, 8th edition, James N.Gilbert.Upper Saddle River, New Jersey

camprosa conference 8 - 11 November 2011


Forensic investigation

FORENSIC INVESTIGATION

  • A detailed forensic investigation of the crime scene offers investigators the best chance of gleaning crucial information and evidence which may lead to the solving of a case

  • Investigators are advised to take advantage of the full range of specialist services available to them

  • The recovery of forensic material from a crime scene has the potential to provide evidence to identify the perpetrators and link the suspected perpetrator to the elements of the crime

  • Source IMO Resolution A.1025(26) Adopted on 2 December 2009

camprosa conference 8 - 11 November 2011


Concepts

CONCEPTS

  • DNA is the human genetic blueprint of an individual called deoxyribonucleic acid or DNA (Gilbert,2004:313)

  • GENETIC FINGERPRINTING is identifying specific patterns in the arrangement of DNA

    (Gilbert,2010)

  • DNA MOLECULE Two strands of randomly stacked intertwined chemicals forming a double helix resembling a twisted rope. The particular appearance of the bands provide the comparative image for positive identification (Gilbert,2010)

  • CRIMINALISTICS can be defined as the application of physical and biological sciences and technology to the scientific examination of physical evidence (Benett&Hess 2001:21)

  • INDIVIDUALISATION is a process that takes place through comparison, used to establish that a disputed sample when compared is from the same origin (Marais 1992:19)

camprosa conference 8 - 11 November 2011


Dna profiling

DNA PROFILING

  • First used in genetic research & determining paternity cases in the 1970’s

  • 1985 Dr Alec Jeffreys,Univ.of Leicester, England published on identification of individuals on basis of DNA

  • 1987 First conviction obtained using DNA evidence (rapist sent to prison by England's Bristol Crown Court)

  • Most used in murder and rape cases

    Source: Criminal Investigation, 2010, 8th edition, James N.Gilbert.Upper Saddle River, New Jersey

camprosa conference 8 - 11 November 2011


Case study world trade centre mass murder september 11 2001

CASE STUDY : WORLD TRADE CENTRE MASS MURDER, SEPTEMBER 11,2001

  • 2,823 victims

  • 1.2 million tons of debris processed

  • 1,400 vehicles parked within scene processed

  • Destroyed buildings searched for evidence and human remains

    Source: Criminal Investigation, 2010, 8th edition, James N.Gilbert.Upper Saddle River, New Jersey

camprosa conference 8 - 11 November 2011


Sources and location of dna

Sources and location of DNA

  • Eye glasses due to sweat or skin cells

  • Tape or ligature due to skin cells, saliva or hair

  • Dental floss, due to saliva, semen or skin cells

  • On a can due to saliva

  • On the rim of a glass due to saliva

  • The end of a cigarette butt due to saliva

  • On a washcloth, saliva, semen, hair, skin cells, blood

  • On blankets,sheets,pillows,semen,hair,skin cells, blood

  • On a hat,mask,bandanna,sweat, skin cells, hair, saliva

  • Clothing, hair, semen, blood, sweat (Gilbert,2004:316)

camprosa conference 8 - 11 November 2011


Samples

SAMPLES

  • Blood most commonly tested (liquid or dried stain)

  • Semen (sperm cell contains DNA)

  • Hair (root material contains cells necessary for analysis)

  • Successful extraction more dependant on size and condition of sample than age

  • Samples successfully obtained from 2,400 year old Egyptian mummy

  • Case study – Titanic victims buried in Canada

camprosa conference 8 - 11 November 2011


Samples1

SAMPLES

  • DNA can be found in almost any cell of the human body

  • Can be obtained from items such as telephones, briefcases, car keys and gloves (low-copy DNA) New techniques allow criminalists to compare far fewer cells for a successful match

  • Small samples of low copy DNA pose greater risk of contamination as extraneous DNA more easily mixed into and confused with suspect DNA

    Source: Criminal Investigation, 2010, 8th edition, James N.Gilbert.Upper Saddle River, New Jersey

camprosa conference 8 - 11 November 2011


Collection body fluid detection dog

COLLECTIONBODY FLUID DETECTION DOG

camprosa conference 8 - 11 November 2011


Initial walk through

INITIAL WALK THROUGH


Bridge wing

BRIDGE WING

camprosa conference 8 - 11 November 2011


The investigation

THE INVESTIGATION


Source of possible evidence

SOURCE OF POSSIBLE EVIDENCE

camprosa conference 8 - 11 November 2011


Evidence collection

EVIDENCE COLLECTION

camprosa conference 8 - 11 November 2011


Source

SOURCE

camprosa conference 8 - 11 November 2011


Source1

SOURCE

camprosa conference 8 - 11 November 2011


Source2

SOURCE

camprosa conference 8 - 11 November 2011


Forensic evidence

FORENSIC EVIDENCE

camprosa conference 8 - 11 November 2011


Dna database south africa

DNA DATABASE: SOUTH AFRICA

The South African Police Service Annual Report for 2010/2011 indicates that during the period of the report

  • 63 627 DNA samples were received for analysis

  • 100 026 DNA samples were analysed

  • 92% of DNA samples were analysed within 35 days

    Biology section- responsible for analysis of evidentiary material of biological origin,e.g. Body fluids, human tissue and hair with the aim of human identification through forensic DNA analysis and microscopial comparison

camprosa conference 8 - 11 November 2011


South african police service

SOUTH AFRICAN POLICE SERVICE

  • The South African Police Service Annual Report for 2010/2011 indicates that evidence collection kits were introduced to facilitate the collection and laboratory processing of DNA samples and that these kits have assisted in protecting the integrity of exhibits and to ensure improved results in the laboratory.

camprosa conference 8 - 11 November 2011


Malmo declaration international conference on piracy at sea 17 19 october 2011 malmo sweden

MALMO DECLARATION INTERNATIONAL CONFERENCE ON PIRACY AT SEA 17 – 19 OCTOBER 2011, MALMO,SWEDEN

The participants at the International Conference on piracy at Sea (ICOPAS)

CALL ON companies and individuals to:

  • Facilitate prosecutions by assisting the International Police Organisation (INTERPOL) response teams, where possible, in preserving evidence at the scene of the crime

camprosa conference 8 - 11 November 2011


In conclusion

IN CONCLUSION

  • Most significant breakthrough in forensic science since the development of fingerprints

  • DNA can identify an individual to a certainty of one in a trillion

  • DNA has demonstrated the innocence of a significant number of accused suspects

  • Used to solve cold cases

  • Can be used to create data base similar to national fingerprint system

    Source: Criminal Investigation, 2010, 8th edition, James N.Gilbert.Upper Saddle River, New Jersey

camprosa conference 8 - 11 November 2011


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