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Unit 6: Forensic Anatomy :. Fingerprints. Fingerprint evidence is one of the most positive investigative means of identifying people . Dactyloscopy The study of fingerprints. Historically - PowerPoint PPT Presentation
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UNIT 6: FORENSIC ANATOMY:
FingerprintsFingerprint evidence is one of the most
positive investigative means of identifying people.
Chapter 4
DactyloscopyThe study of fingerprints
Historically William Herschel—required Indians to put their fingerprints
on contracts, and also as a means of identifying prisoners Henry Faulds—claimed that fingerprints did not change
over time and that they could be classified for identification Alphonse Bertillon—proposed body measurements as a
means of identification; termed anthropometry Francis Galton—developed a primary classification scheme
based on loops, arches and whorls. Edward Richard Henry—in collaboration with Galton
instituted a numerical classification system Juan Vucetich—developed a fingerprint classification based
on Galton’s that is used in Spanish-speaking countries
Chapter 4
Fundamental Principlesof Fingerprints
A fingerprint is an individual characteristic. (formed before birth)
A fingerprint will remain unchanged during an individual’s lifetime.(different even on identical twins)
Fingerprints have general characteristic ridge patterns that permit them to be systematically classified.
Chapter 4
Principles of fingerprints
1. fingerprints are unique 2. Fingerprints do not
change with age Fingerprints displace
unique patterns
Chapter 4
Al Copone
: tried to hid his fingerprints by dissolving his finger tips in acid.
Chapter 4
Ridge CharacteristicsMinutiae—characteristics of ridge patterns
Ridge ending Short ridge Dot or fragment Bifurcation Double bifurcation Trifurcation Bridge Island Enclosure Spur
Basic structures of fingerprints Examples of ridge characteristics used in point-by-point comparisons: Bifurcation: The point at which one ridge forks out into two separate ridges Ridge ending: The point at which a ridge ends Short ridge: A small, short ridge which looks similar to an island Enclosure: An area completely enclosed by ridges
Chapter 4
Fingerprint Minutiae
Structure of the skin
Fingerprints Have General Ridge Patterns That Permit Them to be Systematically Classified: Loops, Whorls & Arches
Loop - one or more ridges enters one side, curves and exits same side
Radial Loop - opens towards the thumb Ulnar loop - opens towards the little finger
Left Loop
Right Loop
Chapter 4
Loop A loop must have one or
more ridges entering and exiting from the same side. Loops must have one delta.
Types Radial—opens toward the
thumb Ulnar—opens toward the
“pinky” (little finger) Which type of loop is this, if it
is on the right hand? Left hand?
Whorls Whorl - forms a revolution around the center Plain Whorl - one or more ridges form a complete revolution around the center;
have two or more deltas Central Pocket Loop - variation of the plain whorl; some ridges tend to form a
loop pattern which recurves and surrounds a whorl in the center Double Loop (twinned loop) - another type of whorl; two separate loop
formations surround each other
Chapter 4
Whorl A plain or central pocket whorl
has at least one ridge that makes a complete circuit. A double loop is made of two loops. An accidental is a pattern not covered by other categories. Whorls have at least two deltas and a core.
Types Plain Central Pocket Double Loop Accidental
Arch Arch - one or more ridges enters one side, rise to a wave, and exits
the opposite side Plain Arch - smooth curved wave in the center; exits smoothly on
the opposite side Tented Arch - variation of plain arch in which the ridges at the
center are thrust upward in a more abrupt manner
Arch
Arches cont. All fingerprints can be classified into three
general groups: loops (60-65%), whorls (30-35%) and arches (5%). These form the basis for all ten-finger classification systems currently in use.
Tented Arch
Chapter 4
Arch
An arch has friction ridges that enter on one side of the finger and cross to the other side while rising upward in the middle. They do NOT have type lines, deltas, or cores.
Types Plain Tented
Chapter 4
Primary ClassificationThe Henry—FBI Classification
Each finger is given a point value based on whorl patterns
right left
Chapter 4
Primary Classification
Assign the number of points for each finger that has a whorl and substitute into the equation:
right right left left left index ring thumb middle little + 1
right right right left left thumb middle little index ring +1
That number is your primary classification number
=
Chapter 4
Comparison
There are no legal requirements in the United States on the number of points. Generally, criminal courts will accept 8 to 12 points of similarity.
Chapter 4
Methods of detecting fingerprints:
The method used depends on the type of print and the type of surface the print is found on
1. Light enhanced: used oblique lighting or a laser to see hidden prints
2. Powder: black is still the most common
3. Iodine fuming: oldest development used on porous material ex paper
Chapter 4
4. Ninhydrin: used on porous surfaces, can be used for developing prints as old as 15yrs. Development is sprayed on and develops overnight
5. Physical developers: ex silver nitrate, used on surfaces that had previously been wet
6. Superglue fuming: cyanoacrulate fumes, preserves the print
Laser Light Without Chemical Treatment
Chapter 4
Latent Prints Latent fingerprints are those that are not visible to
the naked eye. These prints consist of the natural secretions of human skin and require development for them to become visible.
Most secretions come from three glands: Eccrine—largely water with both inorganic
(ammonia, chlorides, metal ions, phosphates) and organic compounds (amino acids, lactic acids, urea, sugars). Most important for fingerprints.
Apocrine—secrete pheromones and other organic materials.
Sebaceous—secrete fatty or greasy substances.
Chapter 4
Developing Latent Prints Developing a print requires substances that interact
with secretions that cause the print to stand out against its background. It may be necessary to attempt more than one technique, done in a particular order so as not to destroy the print.
Powders—adhere to both water and fatty deposits. Choose a color to contrast the background.
Iodine—fumes react with oils and fats to produce a temporary yellow brown reaction.
Chapter 4
Developing Latent Prints
Ninhydrin—reacts with amino acids to produce a purple color.
Silver nitrate—reacts with chloride to form silver chloride, a material which turns gray when exposed to light.
Cyanoacrylate—“super glue” fumes react with water and other fingerprint constituents to form a hard, whitish deposit.
In modern labs and criminal investigations, lasers and alternative light sources are used to view latent fingerprints. These were first used by the FBI in 1978. Since lasers can damage the retina of the eye, special precautions must be taken.
Chapter 4
First thing to do after visualizing a fingerprint
First photograph the print, then you can lift it
Chapter 4
Iodine Fingerprint
Chapter 4
Ninhydrin Fingerprint
The Super Glue Method of developing latent fingerprints
Cyanoacrylate Fingerprints
Chapter 4
Other Prints
Ears—shape, length and width Voice—electronic pulses measured on a
spectrograph Foot—size of foot and toes; friction ridges on the foot Shoes—can be compared and identified by type of
shoe, brand, size, year of purchase, and wear pattern.
Chapter 4
Other Prints
Footprints are taken at birth as a means of identification of infants.
Chapter 4
Other Prints
Lips—display several common patterns
Short vertical lines Short horizontal lines Crosshatching Branching grooves
A More Recent Crime
A bank robber was startled by an alarm just as the teller handed her the money. She grabbed it and in her haste to get away, ran smack dab into a glass door. Nevertheless, she recovered and got away. Subsequent examination of the door revealed a red lipstick imprint of the perpetrator’s mouth. Later police picked up a suspect, but needed evidence to link her to the robbery.
http://www.hbo.com/autopsy/episode/episode_6_the_telltale_imprint.html
Lip PrintsLip prints are different and can be used to identify suspects. There are several general patterns:
Lip PrintsWhat happened?Of several suspects, one was identified by matching his lip print to that on the bank door. The lipstick used by the suspect could also have been compared to the residue on the door. How?
Chromatography of Lipsticks
Thin layer chromatograph (TLC) can be used to separate the components of a lipstick. The chromatograms can then be compared for a match.
Chapter 4
Other Prints
Teeth—bite marks are unique and can be used to identify suspects. These imprints were placed in gum and could be matched to crime scene evidence.
Chapter 4
Visible prints
Print left behind by either leaving the ridge impression or removing dust in a pattern defined by your print
A fingerprint embedded in soft material is called a plastic print
Chapter 4
Other Prints
The blood vessel patterns in the eye may be unique to individuals. They are used today for various security purposes.
: Human Remains
“There is a brief but very informative biography of an individual contained within the skeleton, if you know how to read it…”
—Clyde Snow, Forensic Anthropologist
Forensic anthropologists apply standard scientific techniques developed in physical anthropology to identify human remains, and to assist in the detection of crime.
Forensic anthropologists frequently work in conjunction with forensic pathologists, odontologists, and homicide investigators to identify a decedent, the manner of death, and/or the postmortem interval.
In addition to assisting in locating and recovering suspicious remains, forensic anthropologists work to suggest the age, sex, ancestry, stature, and unique features of a decedent from the skeleton.
forensic anthropologists
The identification of skeletal, badly decomposed, or otherwise unidentified human remains is important for both legal and humanitarian reasons.
Forensic anthropologists frequently work in conjunction with forensic pathologists, odontologists, and homicide investigators to identify a decedent, the manner of death, and/or the postmortem interval.
, forensic anthropologists work to suggest the age, sex, ancestry, stature, and unique features of a decedent from the skeleton.
The Pathologist
Determines the time of death. This can be done most accurately if the body is found within the first 24 hours of death
Uses certain indicators such as algor, livor and rigor mortis.
Rigor Mortis Temperature Stiffness Approximate Time of body of body Since Death
• Warm
• Warm
• Cold
• Cold
• Not stiff
• Stiff
• Stiff
• Not stiff
•Not dead more than 3 hrs
•Dead between 3 and 8 hrs
•Dead 8 to 30 hours
•Dead more than 30 hours
The rigidity of skeletal muscles after death.
Livor Mortis Livor mortis is the settling of blood, resulting in a
reddish or purplish color pattern. Lividity can indicate the position of the body after
death. When lividity becomes fixed, then the distribution of the pattern will not change even if the body’s position is altered.
Lividity usually becomes fixed between 10 and 15 hours after death.
Algor MortisAlgor mortis is the cooling rate of the body after death. At a crime scene, the body temperature is obtained through:
Rectal temperature Liver temperature
Glaister equation:98.4°F - internal temperature/1.5 = hours elapsed since death
Generally the body cools 1 to 12 degrees Fahrenheit until it reaches the surrounding temperature
Effects that Influence Algor Mortis
Temperature of the surrounding environment
Type of clothing on the body Wetness of the clothing Air movement Layers of clothing Size of the individual
Forensic Anthropology
The identification of skeletal, badly decomposed, or otherwise unidentified human remains is
important for both legal and humanitarian reasons.
Forensic Anthropology
A forensic anthropologist may provide basic identification information of skeletonized or badly decomposed remains.
From a whole bone or part of a bone, the scientist may be able to determine:
An age range Sex Race Approximate height Cause of death, disease, or anomaly
OsteologyStudy of bones206 bones in an adult humanFunction of bones:
Provides structure and rigidity Protects soft tissue and organs Serves as an attachment for muscles Produces blood cells Serves as a storage area for minerals Can detoxify the body by removing heavy metals and other foreign elements
from the blood
AGE:Osteologist have developed methods to
determine an individual’s age at the time of death by the skeletal remains.
Age Determination
Most accurate estimations from: Teeth Epiphyses or growth plates Pubic symphysis Cranial sutures: the three major cranial sutures appear as distinct lines in youth and
gradually close from the inside out.
Investigators always use an age range because of the variation in people and how they age.The investigator does not want to eliminate any possibilities for identification.
Age Determination Using Cranial Sutures
Sagittal suture completely closed Males—26 or older Female—29 or older
Sagittal suture is complete open Male—less than 32 Female—less than 35
Complete closure of all three major sutures Male—over 35 Female—over 50
Sagittal suture
Lambodial Coronal
Age Determination Using Basilar Suture
Basilar Suture Technically known as the
synchondrosis spheno-occipitalis, closes in females as young as 14 and in males as young as 16. If the suture is open, the individual is generally considered 18 or younger.
Age Determination
Using EpiphysisStage of Unionof Medial Clavicle
Male Female
Non-union without separate epiphysis
21 or younger 20 or younger
Non-union with separate epiphysis
16-21 17-20
Partial union 17-30 17-33
Complete union 21 or older 20 or older
Age Determination Using Epiphysis
Stage of Unionof the Iliac Crest
Male Female
Non-union without separate epiphysis
16 or younger 11 or younger
Non-union with separate epiphysis
13-19 14-15
Partial union 14-23 14-23
Complete union 17 or older 18 or older
Cranial development in children ages 0-5 years of age
The calvarium is much larger in relation to the face and mandible at this stage in life
The teeth are very important indicators of age in children this young because developmental patterns are well known.
Dental development in children ages 0-5 years of age
The stage of dental development seen here is approximately in the fifth year of life.
The deciduous teeth are becoming more spaced, the first and second deciduous molars are fully erupted, and you can see the sixth
COMPARISON OF A 5 YEAR AND A NEONATAL SKULL
AGE DIFFERENCES
Examples of skeletal development in young adults, ages 18-23.
Examples of skeletal development in older adults, ages 60-70+
Examples of skeletal development in older adults, ages 60-70+
COLLAPESED VERTEBRA BODY
COMPARISON OF A 5 YEAR OLD SKULL AND THAT OF A 60+ YEAR OLD
SEX: Another determination that must be made is the sex of
the individual. Often, skeletons are found after there has been too much deterioration to determine the sex of the
individual.
DETERMINING SEX BASED ON SKULL CHARACTERISTICS
DETERMINING SEX FROM THE FEMUR:
Gender Differences in Bones
The pelvis of the female is wider. Males have a narrow subpubic angle (A) and a narrow pubic body (B).
Gender Differences
The ribcage and shoulders of males are generally wider and larger than that of females. In addition, about one person in twenty has an extra rib. This is more common in males than in females.
Gender Differences
In males the index finger is sometimes shorter than the third finger. In females, the first finger is sometimes longer than the third finger. This is not often used as an indicator of gender as there are many exceptions.
Is this a male or female hand according to the above rule?
RACE: Determining the race of a skeleton can be very difficult. It is based on the common characteristics of individual races rather
than on hard fast rules. Because race can be a very important factor to identify the individual it
is usually considered. Generally, the most important bone for race determination is the skull. The following table gives you an idea of the type of criteria used by
scientist.
CHARACTERISTICS FOR DETERMINING RACE
Characteristic Mongoloid American Indian Caucasoid Polynesian Negroid
Cranial Form broad medium-broad medium highly variable long
Soggital Outline high,globular
medium-low sloping
fronthigh,roundeq medium highly variable
Nose Form medium medium narrow medium broadNasal Bone
Size small med/ large large medium med/small
Incisor Form shoveled shoveled blade blade blade
Orbital Form round Rhomboid rhomboid rhomboid round
Mandible robust robust medium robust rocker form
gracile oblique angle
Chin Projection moderate moderate prominent moderate reduced
Race Characteristics
Caucasoids—have a long, narrow nasal aperture, a triangular palate, oval orbits, narrow zygomatic arches and narrow mandibles.
Negroids—have a wide nasal aperture, a rectangular palate, square orbits, and more pronounced zygomatic arches. The long bones are longer, have less curvature and greater density.
Mongoloids—have a more rounded nasal aperture, a parabolic palate, rounded orbits, wide zygomatic arches and more pointed mandibles.
What differences do you notice between these three skulls? Can you
determine race?
RACE DETERMINATION NEGROID: AMERICAN INDIAN:
CAUCASIAN SKULL
Retention of the metopic suture is generally a caucasoid trait
STATURE: Stature refers to a person’s height. By measuring the length, density and width of bones,
osteologist can make a fairly good estimate of an individual’s stature.
Often estimations are made with just a single bone. However, the fewer the bones, the less exact is the guess.
Estimation of Height
The height of a person can be calculated by using the length of certain long bones, including the femur, tibia, humerus, and radius. Below are the equations to determine average measurements for both male and female. (All measurements are in centimeters)
Male Female
femur x 2.23 + 69.08 femur x 2.21 +61.41tibia x 2.39 + 81.68 tibia x 2.53 + 72.57humerus x 2.97 + 73.57 humerus x 3.14 + 64.97radius x 3.65 + 80.40 radius x 3.87 + 73.50
OdontologyThe identity of an individual can be determined by comparing a person’s teeth to their dental records. Unusual features including the number and types of teeth and fillings, the spacing of the teeth, and/or special dental work (bridges, false teeth, root canals) help to make a positive identification.
Odontology andIdentification
Teeth are often used for body identification because: They are the hardest substances in the body They are unique to the individual X-rays are a good record of teeth
DISEASES AND ABMORMALITY ANALYSIS
Further work may be needed to identify the skeletal remains. Thus osteologist look for more unique qualities
about the bones. This would include bone disease, or damage
PHOTO 1. SHOWS ARTHRITIS PHOTO 2 SHOWS PERIDONTAL DISEASE
PHOTO 3 SHOWS DENTURES PHOTO 4 SHOWS HEALED FRACTURE
SURGICAL RECONSTRUCTION
The surgical reconstruction of the face is very distinctive and provided a solid identification
GUNSHOT WOUNDS
Carnivores: This is a full view of the damaged femur. Notice how the ends
seem to be the preferred part of the bone
Teeth can leave many different types of markings on bones. Here are two examples of the marks that a canine tooth can leave. Canines create holes which go through to the marrow (a), or
impressions like this one (b).
Habitual, strenuous activity Ball and socket joints present a special risk because they allow greater mobility thereby
increasing the risk of injury to the soft tissues and bone.
The head of the humerus and glenoid cavity shown in this photograph were in complete contact for many years prior to this individual's death.
The surfaces are smooth and shiny, indicating that the joint capsule and cartilage had worn away, allowing bone on bone contact in the cavity.
Skeletal information Know difference between axial and appendicular skeleton Know that the hyoid bone is crushed during strangulation Know about fontanels Know the types of vertebrae ( cervical-7, thoracic -12,
lumbar-5, sacrum, coccyx) Know the different types of fractures of bones
Skeletal information
Difference between male and female pelvis: 1 female heavier and rougher bones Pubic arch greater than 90 female less 90 male Male pelvis narrow and deep Cavity of male pelvis smaller than female
Facial Restoration
After determining the sex, age, and race of an individual, facial features can be built upon a skull to assist in identification. Erasers are used to make tissue depths at various points on the skull. Clay is used to build around these markers and facial features are molded.
The Body FarmThe nickname of a two and a half acre research facility in Tennessee developed in 1980 by Bill Bass where bodies are placed in various conditions and allowed to decompose. Its main purpose is to observe and understand the processes and timetable of postmortem decay. Over the years it has helped to improve the ability to determine "time since death" in murder cases.Hic locus est ubi mortui viveuntes docent. This is the place where the dead teach the living.
Facial Reconstruction
When skeletal remains are found, and the victim remains unidentified after traditional
means of identification fail, investigators may call upon the forensic artist to utilize the three-dimensional facial reconstruction
technique
Subject, age 4 yrs. Subject, age 11 yrs. Subject, age12 yrs, sisters ages 14 and 22 yrs
Mother, age 4 yrs Mother, age 11 yrs Mother, age 14 yrs Parents ages 22 yrs
Subject aged to 22 yrs Life Photo age 22 yrs
Death Photo Computer Sketch Sketch from Body Life Photo
Three-dimensional Facial Reconstruction
Frontal View of Skull
Three-dimensional facial reconstruction
techniqueThe three-dimensional process is initiated by placing the skull on a workable stand, where the skull can easily be tilted and turned in all directions
By utilizing proper tissue depth data can be used to determine race, gender, and age
Artificial eyes are placed in the skull’s eye sockets, centered and at the proper depth
three-dimensional facial reconstruction
techniqueInformation such as geographic location of where the deceased lived, his or her lifestyle, and the various information provided to the artist by the Forensic Anthropologist and other professionals, is heavily relied upon when completing the reconstruction.
Hair is accomplished by means of a wig, or by applying clay to represent hair.
Various items (props), such as glasses, clothing, hats, etc. may be applied to better accentuate the features of the individual
three-dimensional facial reconstruction
techniqueThe tissue markers are glued directly onto the skull. Clay will be systematically applied directly on the skull, following
the skull's contours; paying strict attention to the applied tissue markers
Various measurements are made, and logged, to determine nose thickness/length, mouth thickness/width, and eye placement
three-dimensional facial reconstruction
techniqueUpon completion, the sculpture is photographed. All procedures are documented and working notes
collected. When executed properly, this technique is proven to have a
high success rate.
Unidentified White Male
The victim was discovered on February 15, 2002 in Hillsborough County, Florida. Estimated Date of Death is 5 or 6 months prior to the discovery of the body. Skeletal remains used for reconstruction purposes
Unidentified White Male
Estimated age: 55 - 65 years old
Approximate Height and Weight: 5'8"; weight unknown
Distinguishing Characteristics: Brown hair. Evidence of old (healed) facial trauma near the right eye.
Dentals: All teeth missing well prior to death.
Clothing: Tattered white plastic pants with elastic waistband, dark pin-striped men's suit jacket, and a "Faded Glory" brand, entirely tattered t-shirt.
Unidentified White Female
The victim was discovered on December 6, 1995 in Jacksonville, Onslow County, North Carolina.
State of remains: Skeletal. Estimated Date of Death:
Less than 2 years prior to discovery.
The department has not ruled the death a homicide because there was little evidence.
Unidentified White Female Vital Statistics
Estimated age: 32 - 38 years old Approximate Height and Weight: 5'6" Distinguishing Characteristics: Hair may have been brown. Dentals: Expensive and extensive dental work. Tooth 19 had a root canal and had been cut for a
crown, the crown was missing. She had protruding teeth. Clothing: Around her remains, investigators found two New York Transit Authority tokens, two
keys with a partially burned key tag, a pair of broken glasses and several coins. The clothing found was a pair of white Nike tennis shoes, size 9; black Lee jeans and a red sweatshirt. Near the body was a thin 18 k gold necklace, two gold bangle bracelets and two gold hoop earrings.
Instructions for Facial
Reconstruction LabAfter you have completed your facial reconstruction, your
group will need to turn in a report with photograph of face if possible with the following information:
Identify your missing personInclude case historyInclude vital statisticsSee next page for example
Unidentified Black Female The victim was discovered on December 16, 1999 in Tampa, Hillsborough County, Florida. Estimated Date of Death: Several years + Skeletal remains Remains consist of skull/jawbone only
Vital Statistics Estimated age: 20 - 40 years old
Other: Voodoo materials located.
Case History On December 16, 1999 the skeletal remains of a black female was located in a public storage facility in Tampa. Remains consist of skull/jawbone only. According to The Department of Anthropology at the University of South Florida, "the mandibular molar displays some enamel crown wear suggesting a diet not typical of modern Americans, perhaps with more grit than is customarily found today in this country. "
Read Forensics true crime scene investigation pg 71-76 Jesus
