Forensics Science - Belle Vernon Area School District

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Define forensics science.
When did fingerprinting identification
come about?
When was the first polygraph used?
When was the FBI created?
When did the fingerprinting become
computerize?
 1.What
were the names of the victims in
the OJ Simpson case?
 What pieces of evidence was there to link
OJ to the crime scene.
 What two pieces of evidence finally
convicted Ted Bundy?
 What
are the two layers of the skin?
 Which layer is alive?
 Which layer do fingerprints come from?
 What are the three most common
fingerprints?
 Name and describe any three points on a
fingerprint.
 What
percent of finger prints are whorled?
 Name
and describe the four types of
whorled fingerprints.
 What
is the most common type of finger
print?
 Name
and describe the two types of
looped fingerprints.
 Name
the type of surfaces that dusting,
iodine & super glue fuming is best used
for?
 How
many points are needed for a positive
identification?

Sherlock Holmes, Perry Masons, Law and Order
and CSI. (Jobs like those depicted in C.S.I. don't
exist. Make sure you have realistic
expectations before diving in).

Forensic science may generally be defined as
the application of scientific, technical, or other
specialized knowledge to assist courts in
resolving questions of fact in civil and criminal
trials.

forensic biology (DNA, blood, body fluids, etc.)
 fingerprints
 hair
History Of Forensics
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Begins in BC with fingerprints in early painting of
prehistoric humans.
1784 John Toms was convicted of murder on the basis
of the torn edge of wad of newspaper in a pistol matched
the remaining piece in his pocket.
1813 Mathiew Orfila father of modern toxicology –
developed tests for the presence chemicals in the blood
and is also credits with the first attempt to use a
microscope in the assessment of blood and semen
stains.
1835 Henry Goddard first to use a bullet comparison to
catch murder
1879 Virchow first to use hair and recognize its
limitations.
1884 Alfred Dreyfus was convicted of treason in France
based on hand writing.
1901 Sir Edwards Richard Henry Fingerprint
identification
8. 1901 Henry Deforrest pioneered the first systematic use
of fingerprints in the US.
9. 1904 Oskar and Rudolf Adler developed a presumptive
test for blood.
10. 1921 John Larson and Leonard Keeler designed the
first portable polygraph.
11. 1924 August Vollmer first police crime lab in LA.
12. 1932 FBI was created.
13. 1984 Sir Alec Jefferys developed the first DNA profiling
test.
14. 1986 First case to use DNA to solve a crime
15. 1996 FBI computerize Searches for Fingerprint
database.
“The Trial of the Century”
Besides his Hall of Fame career, Simpson is
infamous for having been tried for the murder of
ex-wife Nicole Brown Simpson and her friend
Ronald Goldman in 1994. He was acquitted in
criminal court in 1995 after a lengthy, highly
publicized trial.
In 1997, Simpson was found liable for their deaths
in civil court, but to date has paid little of the
$33.5 million judgment
He gained further notoriety in late 2006 when he
wrote a book titled If I Did It. The book, which
purports to be a first-person fictional account of
the murder had he actually committed it, was
withdrawn by the publisher just before its
release.
The book was later released by the Goldman family
and the title of the book was expanded to If I Did
It: Confessions of the Killer).
www.cnn.com/US/OJ/suspect/index.html
Evidence linking him to the
murders.

DNA of Nicole Brown, Ronald Goldman, & OJ
Simpson was found at the scene.

Shoe prints found at the crime scene were from
a size 12 Bruno Magli shoe, and bloody shoe
impressions on the Ford Bronco carpet was
consistent with a Bruno Magli shoe.

Simpson wore a size 12 shoe.
Ted Bundy

Theodore Robert 'Ted' Bundy (November 24,
1946 – January 24, 1989) was an American
serial killer.

Bundy raped and murdered scores of young
women across the United States between 1974
and 1978.
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After more than a decade of vigorous denials,
Bundy eventually confessed to 29 murders,
although

he actual total of victims remains unknown.
Typically, Bundy would rape his victims, and
then murder them by bludgeoning, and
sometimes by strangulation. He also engaged in
necrophilia.

In stark contrast to the brutality of his crimes,
Bundy was frequently described as educated
and charming. His friends and acquaintances
would remember him as a handsome and
articulate young man.
Ted Bundy Time Line
January 4 - July 14,1974– Washington State
October 2, 74 – May 6,1975 –Utah State
Arrested August 16, 1975 Escaped from Aspen Jail by jumping from
the library, found 8 days latter driving a car weaving in and out of
traffic.
Escaped again in December 30, 1977
Bundy crawled over to a spot directly above the jailer's linen closet
— the jailer and his wife were out for the evening — dropped down
into the jailer's apartment, and walked out the door.
January 15 – February 9 1978 Florida State (Chi Omega) - Bundy
traveled to Lake City, Florida. While there, he abducted, raped, and
murdered 12-year-old Kimberly Leach, throwing her body under a
small pig shed.
Two pieces of evidence proved crucial.
First, Chi-Omega member Nita Neary, getting back
to the house very late after a date, saw Bundy
as he left, and identified him in court.
Second, during his homicidal frenzy, Bundy bit
Lisa Levy in her left buttock, leaving obvious bite
marks. Police took plaster casts of Bundy's teeth
and a forensics expert matched them to the
photographs of Levy's wound. Bundy was
convicted on all counts and sentenced to death.
Oklahoma City Bombing
April 19, 1995 aimed at the Alfred P. Murrah Federal Building, a U.S.
government office complex in downtown Oklahoma City, Oklahoma.
The attack claimed 168 lives and left over 800 injured.
Timothy McVeigh arrest 90 minutes later from a vin number from a
bomb car.
Teeth from victims helped identified 25% of the bodies.
Madrid Bombings

Three of the trains set off from Alcala de Henares, about
12km to the east of Madrid. The fourth originated from
Guadalajara, but passed through the station en route for
the city.

On the morning of 11 March 2004 (three days before
Spain's general elections), killing 191 people and
wounding 2,050.

That afternoon, detectives looked more carefully at the
white van. They collected fingerprints, and under the
passenger seat they found a plastic bag with seven
detonators matching the type used in the bombings
The Verdict
History of Fingerprints
1.
The oldest known documents showing fingerprints date
from third century B.C. China.
2.
In ancient Babylon (dating back to 1792-1750 B.C.),
fingerprints pressed into clay tablets marked contracts.
3.
The earliest written study (1684) is Dr. Nehemiah’s
paper describing the patterns he saw on human hands
under a microscope, including the presence of ridges.
4.
In 1788, Johann Mayer noted that the arrangement of
skin ridges is never duplicated in two persons. He was
probably the first scientist to recognize this fact.
History of Fingerprints
5.
Nine fingerprint patterns were described in
1823 by Jan Evangelist Purkyn.
6. Sir William Herschel (shown at the right), in
1856, began the collection of fingerprints and
noted they were not altered by age.
7. Alphonse Bertillon created a way to identify
criminals that was used in 1883 to identify a
repeat offender.
8. In 1888, Sir Francis Galton (shown at the
right), and Sir Edmund Richard Henry,
developed the fingerprint classification system
that is still in use in the United States.
In 1686, Marcello Malpighi, a professor of anatomy at the University of Bologna,
noted in his treatise; ridges, spirals and loops in fingerprints.
In 1823, John Evangelist Purkinje, a professor of anatomy at the University of
Breslau, published his thesis discussing 9 fingerprint patterns.
In 1882, Gilbert Thompson of the U.S. Geological Survey in New Mexico, used his
own thumb print on a document to prevent forgery.
In Mark Twain's book, "Life on the Mississippi", a murderer was identified by the use
of fingerprint identification.
Sir Francis Galton, a British anthropologist and a cousin of Charles Darwin, began
his observations of fingerprints as a means of identification in the 1880's.
Juan Vucetich, an Argentine Police Official, began the first fingerprint files based on
Galton pattern types.
Juan Vucetich made the first criminal fingerprint identification in 1892. He was able
to identify Francis Rojas, a woman who murdered her two sons and cut her own
throat in an attempt to place blame on another.
The Fingerprint Branch at New Scotland Yard (London Metropolitan Police) was
created in July 1901 using the Henry System of Classification.
First systematic use of fingerprints in the U.S. by the New York Civil Service
Commission for testing. Dr. Henry P. DeForrest pioneers U.S. fingerprinting.
The New York State Prison system began the first systematic use of fingerprints in
U.S. for criminals.
1905, U.S. Army begins using fingerprints.
1907, U.S. Navy begins using fingerprints.
1908, U.S. Marine Corps begins using fingerprints.
By 1946, the FBI had processed 100 million fingerprint cards in manually maintained
files; and by 1971, 200 million cards.
2007, The largest AFIS repository in America is operated by the Department of
Homeland Security's US Visit Program, containing over 74 million persons'
fingerprints, primarily in the form of two-finger records.
History of Fingerprints
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Fingerprints offer an infallible means of personal identification.
That is the essential explanation for their having supplanted other
methods of establishing the identities of criminals reluctant to
admit previous arrests.

The science of fingerprint Identification stands out among all
other forensic sciences for many reasons, including the
following:
Has served all governments worldwide during the past 100
years to provide accurate identification of criminals. No two
fingerprints have ever been found alike in many billions of
human and automated computer comparisons. Fingerprints
are the very basis for criminal history foundation at every
police agency.
Established the first forensic professional organization, the
International Association for Identification (IAI), in 1915.
Established the first professional certification program for
forensic scientists, the IAI's Certified Latent Print Examiner
program (in 1977), issuing certification to those meeting
stringent criteria and revoking certification for serious errors such as
erroneous identifications.
Remains the most commonly used forensic evidence worldwide - in
most jurisdictions fingerprint examination cases match or outnumber
all other forensic examination casework combined.
Continues to expand as the premier method for identifying persons,
with tens of thousands of persons added to fingerprint repositories
daily in America alone - far outdistancing similar databases in growth.
Outperforms DNA and all other human identification systems to
identify more murderers, rapists and other serious offenders
(fingerprints solve ten times more unknown suspect cases than DNA
in most jurisdictions).
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Other visible human characteristics change - fingerprints do not. In
earlier civilizations, branding and even maiming were used to mark
the criminal for what he was. The thief was deprived of the hand
which committed the thievery. The Romans employed the tattoo
needle to identify and prevent desertion of mercenary soldiers.
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Before the mid-1800s, law enforcement officers with extraordinary
visual memories, so-called "camera eyes," identified previously
arrested offenders by sight. Photography lessened the burden on
memory but was not the answer to the criminal identification
problem. Personal appearances change.

Around 1870, a French anthropologist devised a system to measure
and record the dimensions of certain bony parts of the body. These
measurements were reduced to a formula which, theoretically,
would apply only to one person and would not change during his/her
adult life.
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This Bertillon System, named after its inventor, Alphonse Bertillon,
was generally accepted for thirty years. But it never recovered from
the events of 1903, when a man named Will West was sentenced to
the U.S. Penitentiary at Leavenworth, Kansas. It was discovered
that there was already a prisoner at the penitentiary at the time,
whose Bertillon measurements were nearly the same, and his name
was William West.
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Upon investigation, there were indeed two men who looked exactly
alike. Their names were Will and William West respectively. Their
Bertillon measurements were close enough to identify them as the
same person. However, a fingerprint comparison quickly and
correctly identified them as two different people. (Per prison records
discovered later, the West men were apparently identical twin
brothers and each had a record of correspondence with the same
immediate family relatives.)
What Are Fingerprints?
 All fingers, toes, feet, and palms are covered in small
ridges.
 These ridges are arranged in connected units called
dermal, or friction, ridges.
 These ridges help us get or keep our grip on objects.
 Natural secretions plus dirt on these surfaces leave
behind an impression (a print) on those objects with
which we come in contact.
What makes a fingerprint?
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1) Ridge patterns and the details in small areas of
friction ridges are unique and never repeated.
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2) Friction ridges develop on the fetus in their definitive
form before birth.
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3) Ridges are persistent throughout life except for
permanent scarring.
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4) Friction ridge patterns vary within limits which allow
for classification.
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Identical twins have the same DNA configuration but
they do not have identical friction ridge configuration.
The skin
There are approximately 2,700
ridge "units" per square inch of
friction skin.
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The Epidermis (E) is stratified
(layered), squamous (flat)
epithelial tissue 5 layers thick
and...

The Dermis is much thicker than
the epidermis and consists of two
layers - the Papillary layer (DPL)
an area of loose connective tissue
extending up into the epidermis as
dermal pegs (DP) and the deeper
reticular layer (DRL).
Formation of Fingerprints
 An animal’s external tissue (skin) consists of (a) an inner
dermis and (b) an outer epidermis.
 The creation of fingerprints occurs in a special layer (the
basal layer) in the epidermis where new skin cells are
produced.
 Fingerprints probably begin forming at the start of the
10th week of pregnancy.
 Because the basal layer grows faster than the others, it
collapses, forming intricate shapes.
There are three main types of fingerprints:
visible prints, latent prints and impressed
prints.
Visible prints are also called patent prints and are left in some medium,
like blood, that reveals them to the naked eye. They can be when
blood, dirt, ink or grease on the finger come into contact with a
smooth surface and leave a friction ridge impression that is visible
without development.
Latent prints are not apparent to the naked eye. They are formed from
the sweat from sebaceous glands on the body or water, salt, amino
acids and oils contained in sweat. The sweat and fluids create prints
must be developed before they can be seen or photographed. They
can be made sufficiently visible by dusting, fuming or chemical
reagents.
Impressed prints are also called plastic prints and are indentations left
in soft pliable surfaces, such as clay, wax, paint or another surface
that will take the impression. They are visible and can be viewed or
photographed without development.
Characteristics of
Fingerprints
 Forensic examiners look for the presence of a core (the
center of a whorl or loop) and deltas (triangular regions
near a loop).
 A ridge count is another characteristic that distinguishes
one fingerprint from another. The count is made from
the center of the core to the edge of the delta.
Key points to fingerprints

Endings, the points at which a ridge
stops
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Bifurcations, the point at which one
ridge divides into two
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Dots, very small ridges
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Islands, ridges slightly longer than dots,
occupying a middle space between two
temporarily divergent ridges
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Ponds or lakes, empty spaces between
two temporarily divergent ridges
Spurs, a notch protruding from a ridge
Bridges, small ridges joining two longer
adjacent ridges
Crossovers, two ridges which cross each
other
The core is the inner point, normally in the
middle of the print, around which swirls,
loops, or arches center. It is frequently
characterized by a ridge ending and
several acutely curved ridges.
Deltas are the points, normally at the lower
left and right hand of the fingerprint, around
which a triangular series of ridges center.
Fingerprint Forensic FAQs
 Can fingerprints be erased?
No, if, for example, they are removed with
chemicals, they will grow back.
 Is fingerprint identification reliable?
Yes, but analysts can make mistakes.
 Is fingerprint matching carried out by computers
in a matter of seconds?
No, but the FBI’s Integrated Automated
Fingerprint Identification System (IAFIS or AFIS)
can provide a match in 2 hours for the prints in
its Master File.
Types of prints
Arched
5 % of Pop
Looped
65% of Pop
Whorled
30% of Pop
Characteristics of
Fingerprints
 Basic patterns can be further divided:
 Arch patterns can be plain (4%) or tented (1%).
 Whorl patterns can be central pocket (2%),
double loop (4%), or accidental (0.01%).
 Even twins have unique fingerprints due to
small differences (called minutiae) in the
ridge patterns.
Whorled Finger prints

30% of fingerprints are
whorled.
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4 types of whorled
patterns
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1. Accidental
 2. Plain
 3. Double loop whorled
 4. Central pocket
Looped finger prints
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60-65%
 1. Radial Loop
 2. Ulnar Loop
Problems or disease with finger
printing
Techniques For Lifting a
Print
Dusting
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Used on smooth, non-porous
materials.
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The area is lightly and carefully
dusted with either a black or white
powder, depending on the
contrasting surface.

The dust is lifted with tape and set
against a contrasting background.

The print is preserved via
photography.
Fingerprint dusting in a lab
Iodine Fuming

Suspect material is
placed in an enclosed
cabinate along with
iodine crystals.

The crystals are heated,
and will sublimate (turn
into a gas vapor).

The vapors cause the
prints to visualize.
Fingerprint visualized with
iodine fuming.
Chemical Treatment

Ninhydrin (triketohydrindene hydrate)this chemical is sprayed onto a porous
surface via an aerosol can. Prints
begin to visualize an hour or two after
application, although the process can
be accelerated through heating the
print.
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Silver nitrate- silver nitrate is sprayed
onto the porous surface and left to dry.
Then it is exposed to ultraviolet light to
visualize the prints.
Silver Nitrate spray
bottle
Superglue Fuming
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

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Used mainly on non-porous
materials.
Superglue is placed on
cotton and treated with
sodium hydroxide.
Fumes can also be created
by heating the glue.
The fumes and the object are
contained in a closed
chamber for up to six hours.
The fumes adhere to the
print, visualizing it.
Fuming tank
Analysis of Prints

Prints are analyzed by looking for points of interest or
minutiae.
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If 8-16 match points are made, the fingerprints match.

Nowadays a computer can be used to assist this process
of matching points.

Known criminals are fingerprinted, and the prints are
filed away in a database known as the Integrated
Automated Fingerprint Identification System. If a print
is found at a crime scene, investigators look for a match
in the database.
Fingerprint Forensic FAQs
 How
are latent fingerprints collected?
The Future of Fingerprinting
 New scanning technologies and digitally
identifying patterns may eliminate analytical
mistakes.
 Trace elements of objects that have been
touched are being studied to help with the
identification of individuals.
 To help with identification, other physical
features such as eyes and facial patterns are
also being studied.
. . . . . . . . . . . . . . . . . Summary
 Fingerprints have long been used for identification, and in the mid-
1800s were recognized as unique to each person.
 Three main groups include arches, whorls, and loops.
 Basic analysis includes looking for cores, deltas, and making a ridge
count.
 Investigators search for patent, plastic, and latent prints.
 Dusting with powders or using special chemicals can make latent
fingerprints visible.
 New developments may eliminate errors by analysts.
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