Download FORENSIC CRIME INVESTIGATION : THE ROLE OF DNA

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project

Document related concepts

Microsatellite wikipedia , lookup

DNA profiling wikipedia , lookup

Helitron (biology) wikipedia , lookup

United Kingdom National DNA Database wikipedia , lookup

Transcript
CAMPROSA CONFERENCE
08 – 11 NOVEMBER 2011
On board M.S.C. SINFONIA
camprosa conference 8 - 11 November 2011
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
 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
 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
 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
 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
 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
 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
 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
 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
 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
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
camprosa conference 8 - 11 November 2011
INITIAL WALK THROUGH
BRIDGE WING
camprosa conference 8 - 11 November 2011
THE INVESTIGATION
SOURCE OF POSSIBLE EVIDENCE
camprosa conference 8 - 11 November 2011
EVIDENCE COLLECTION
camprosa conference 8 - 11 November 2011
SOURCE
camprosa conference 8 - 11 November 2011
SOURCE
camprosa conference 8 - 11 November 2011
SOURCE
camprosa conference 8 - 11 November 2011
FORENSIC EVIDENCE
camprosa conference 8 - 11 November 2011
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
 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
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
 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