Vocabulary
Make a flashcard or make a vocabulary page
(see example) in your notebook for each of the
following words:
• Forensic Science
• Anthropometry
• Locard’s Exchange Principle
• Expert Witness
History of
Forensic
Science
Sherlock Holmes, 1887
“I've found it. I've found it," he shouted to my companion, running
toward us with a test tube in hand. "I have found a reagent which is
precipitated by hemoglobin and by nothing else. . . . The old guaiacum
test was very clumsy and uncertain. So is the microscopic examination
for blood corpuscles. The latter is valueless if the stains are a few
hours old. Now, this appears to act as well whether the blood is old or
new. Had this test been invented, there are hundreds of men now
walking the earth who would long ago have paid the penalty for their
crimes. . . . Criminal cases are continually hinging upon that one
point. A man is suspected of a crime months perhaps after it has been
committed. His linen or clothes are examined and brownish stains
discovered upon them. Are they blood stains, or rust stains, or fruit
stains, or what are they? That is a question which has puzzled many
an expert, and why? Because there was no reliable test. Now we have
the Sherlock Holmes test, and there will no longer be any difficulty.”
INTERACTIVE
• After reading the quote from Sherlock
Holmes…write at least 3 sentences about the
quote.
– What do you think?
– Summarize his statement.
– Does anything surprise you?
Definition
• Forensic Science is the
application of science
to the criminal and
civil laws that are
enforced by police
agencies in a criminal
justice system.
• 3 A.D.
Forensics in History
– China; woman suspected of murdering her husband
and then burning the body—claiming he died in an
accidental fire
– Investigators noticed there were no ashes in the
husband’s mouth
– Pig test: burned one alive, burned a dead pig
– Pig that was burned alive had ashes in the mouth, pig
that was already dead when burned did NOT have
ashes in the mouth
– There for the wife was convicted of her husband’s
murder.
Forensics in History
• 1690s, Salem Witch Trials
– Person confessed
– Person was tortured until they confessed
– Sink/Swim test
Video Clip—Salem Witch Trials
• Mid 1700s
Forensics in History
– Age of Enlightenment
– US Declaration of Independence, Constitution
– Innocent until proven Guilty
Forensics in History
• 1800s
– More Science used to examine evidence
– 1879: Anthropometry—created by Alphonese
Bertillon, a systematic procedure of taking body
measurements to distinguish one individual from
another.
– Anthropometry was considered the most accurate
form of personal identification until fingerprinting.
Forensics in History
• 1892, Galton
– First proof that fingerprints are unique to the
individual
– Created the first system of identification by
fingerprints
Forensics in History
• 1880s, Sherlock Holmes
– The character of Sherlock Holmes applied new
techniques such as serology (study of blood),
fingerprinting, firearm identification, and document
examination long before they were used in real
criminal investigations
• 1901, Blood Typing
– Dr. Karl Landsteiner discovered that blood could by
grouped into types A, B, AB, and O
– Blood types could be useful in identifying or
eliminating suspects in an investigation
Forensics in History
• 1910, Questioned Documents
– Albert Osborn wrote a book on document examination.
The book is still used today.
• 1910, Locard’s Principle
– “When two objects come into contact with each other, a
cross-transfer of materials occurs.”
– Locard strongly believed that every criminal can be
connected to a crime by the dust particles carried from the
crime scene.
– Case: someone had made counterfeit coins, there were 3
suspects. Locard examined all 3 person’s clothing under a
microscope. He located small metallic particles which
matched the metallic elements of the coins on all of the
garments. All 3 were convicted.
Edmond Locard
• "Wherever he steps, whatever he touches, whatever he
leaves, even unconsciously, will serve as a silent witness
against him. Not only his fingerprints or his footprints, but
his hair, the fibers from his clothes, the glass he breaks,
the tool mark he leaves, the paint he scratches, the blood
or semen he deposits or collects. All of these and more,
bear mute witness against him. This is evidence that does
not forget. It is not confused by the excitement of the
moment. It is not absent because human witnesses are. It
is factual evidence. Physical evidence cannot be wrong, it
cannot perjure itself, it cannot be wholly absent. Only
human failure to find it, study and understand it, can
diminish its value."
Forensics in History
• 1932, FBI Crime Lab
– FBI crime lab opened under J. Edgar Hoover
Forensics in History
• 1984, DNA
– DNA Typing and Identification was discovered by Sir
Alec Jeffries
INTERACTIVE
• Draw a timeline of the events you recorded in
your notes.
Forensics in Court
• Ultimately all the forensic evidence must be
admissible and hold up in a court of law
• Expert Testimony: testimony given by individuals
with a certain skill or knowledge
• Expert Witness: An individual whom the court
determines to posses a certain skill or knowledge.
Example: entomologist, serologist
• Expert Testimony
INTERACTIVE
• Write a 1 paragraph summary of the “History
of Forensics”