Transcript Chapter Thirteen - Technology in Investigations

Police Technology
Chapter Thirteen
Technology in Investigations
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Learning Objectives






How technology has changed crime scene
protection and evidence gathering
Basic science of DNA
Fingerprint technology
Issues surrounding DNA databases
Digital photography
Investigative software
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Forensic Science
The word forensic comes from the Latin –
Foren. Essentially, it means to debate. In
modern terms it has come to mean bringing
any science into the courtroom. Any science
or specialty brought into the courtroom such
as:

Forensic pathology or forensic accounting
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Transfer Theory
Whenever two objects
come into contact they
exchange evidence of
that contact.
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Chain of Custody



Testimony and documentation that details the
location and condition of evidence from seizure
to trial.
It assures the court that items entered into
evidence are in the same condition as when they
were seized.
The chain of custody and the procedures used
to analyze evidence are more often challenged
than the science behind the analysis.
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Daubert Test


In order for the analysis of evidence to be
used against a defendant, the court must
accept the scientific conclusion as valid.
The standard for accepting scientific
analysis is the Daubert Test – from
Daubert v Merrel Dow Pharmaceuticals,
inc.
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
In the Daubert Test
The Court asks 




Is the science derived by the scientific method?
Has the science been subjected to peer review
or publication?
Does the relevant scientific community generally
accept the science?
What is the error rate of thee scientific
technique used to gain the information?
Are there standards for controlling the
technology used to obtain the scientific
evidence?
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Crime Scenes



A crime scene is any location wherein
evidence of a crime may be located.
For instance, a search of an offender’s
home may yield evidence, but not be the
location the crime occurred.
Protocols for scene protection,
documentation and evidence recovery are
critical at all crime scenes
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Crime Scenes



Photographs provided by OBS INC.,
Specialty Vehicles
Evidence tends to
deteriorate
Investigator’s often
refer to the “golden
hour;” the time when
evidence is best
recovered.
Some jurisdictions are
taking the crime lab
to the crime scene
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Fingerprint Advances

The recovery of latent
(hidden) fingerprints
is not longer
restricted to powder:


Technology has advanced to the
point wherein some jurisdictions
use superglue fuming wands at
the crime scene

Superglue fuming
Laser applications
Unique powders
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Basics



Transfer theory demonstrates that
wherever we are – we leave behind
evidence we where there!
Perhaps our fingerprints; or,
Our bodies are constantly shedding cells,
releasing vapor containing cells and
shedding hair – we leave it everywhere
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Basics
(smaller and smaller)




Our bodies contain 100 trillion cells.
Most cells contain a center piece called a
nucleus.
The nuclei of our cells contain 23 pairs of
chromosomes which are the biological
instructions of who we are
During conception our parents contribute
one half of each pair.
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Basics
(smaller and smaller)


Inside each chromosome there are as
many as a hundred thousand pair of
genes – the fundamental building blocks
of our hereditary traits.
There are many variations for genes, but
really two classifications.


General – those that identify us as humans
Specific – those that give us individual
characteristics
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Basics
(smaller and smaller)


Our genes are made up of
Deoxyribonucleic Acid (DNA)
DNA consists of a long string of four
repeating nucleotides:




Adenine (A)
Cytosine (C)
Guanine (G)
Thymine (T)
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
This long string
of repeating
nucleotides is
called a
polymer
DNA Basics
Cells
(smaller and smaller)
Nucleus
Chromosomes
Genes
DNA
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Basics
(smaller and smaller)

The order of the four nucleotides (A, C, G,
T) within the polymer determine the
information contained therein.

Different order – different information
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Basics

A complete DNA
molecule has to
polymer strands with
four bases – it is a
tightly woven, double
helix, with 3.3 billion
pairs of nucleotides
Base Pairs
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Basics


DNA, like digital information has beginning
codes and ending codes – to tell us where
“packets of genetic data” or segments
begin and end.
With DNA, at the end and beginning of
DNA stands are A/T and G/C
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Basics



Most of our DNA is exactly the same, only
a small percentage is different from each
other.
The location where specific DNA
information is located is called a locus.
The information that is different between
individuals is called Polymorphisms – the
part examined during forensic DNA
analysis.
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Basics

DNA analysis can compare:


short repeating patterns and look at the
variation in length – called Variable
Number of Tandem Repeats (VTNR)
base pairs – called Polymerase Chain
Reaction (PCR) within Polymorphisms
(specific genes)
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Basics
Recall general and specific genes:


General genes (DNA) are called
Monomorphisms
Specific genes (DNA) are called
Polymorphisms
DNA Analysis is conducted on
Polymorphisms
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Databases


Like fingerprint information, DNA information is
converted to a numerical value for ease of
search.
Combined DNA Information System (CODIS) is
actually a combination of databases.


153 Laboratories in 49 states
Actually includes three different type of databases

Convicted Sex Offender, other offenders, missing persons
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
DNA Databases




Database Concerns
Who is included? Convicted, arrested or
suspected? It varies from state to state.
What about juveniles? While juvenile arrest
records don’t necessarily follow a juvenile into
adulthood, the DNA database does?
Since a portion of DNA information is familial – if
your sibling or parent is in the database – so is a
part of you.
What about research?
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Software
Investigative workload





Case assignment
Clue management
Witness management
Case coordination
Productivity
Screen Capture provided by Crimestar Corporation
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Software
Crime Scene Drawings
Photograph provided by Robert Eplett, California
Governor’s Office of Emergency Services
Crime scene drawings are
often used as a means of
documenting the location
of evidence, assisting in
determining the sequence
of events and explaining a
crime to a jury. Software,
some very similar to drafting
software aids in the
production of two dimension
crime scene representations.
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Software
Link Analysis

Link analysis software
can often help in
organizing the vast
amount of
information and
evidence a complex
case can produce
Screen Capture provided by Pen-Link™
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Digital Photography

Digital photography is a picture stored in the
language a computer can understand. It takes
that information and converts it into a visual
display.


It has numerous benefits like storage and analysis.
Because it is easier to manipulate a digital image than
a traditional photograph, additional software security,
procedures and protocols are necessary to maintain
the chain of custody
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
New Information
High Definition Survey

Using laser technology a three
dimensional representation of a
crime scene is created.
Photograph provided by lecia-geosystems
Hyperlink to more Information
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
New Information
High Definition Survey
Investigators, prosecutors
and juries can now return
to the scene of the crime in
a virtual world.
Reconstruction
Trials
Training
A three dimensional representation of a
seated man with a gun
Photograph provided by lecia-geosystems
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster
Police Technology
Explore Forensic Science at
www.forensicprofiles.com
Copyright 2005 - 2009: Hi Tech Criminal
Justice, Raymond E. Foster