Forensics
What are prints collected on?
"tenprint" cards
Other Areas of Forensic Science
- Forensic Art - Forensic Psychiatry - Forensic Odontology - Forensic Pathology - Forensic Engineering - Computer Forensic - Jurisprudence
What is used to identify and compare fibers?
- Fourier Transform Infrared analysis (FTIR) - Optical microscopy - Pyrolysis gas chromatography-mass spectrometry (PGC-MS)
Where Forensic Scientists Work
- Law enforcement agencies - Forensic Labs - Universities - Hospitals - Consulting offices
What are the problems with fiber evidence?
- class characteristic - the less common the fiber the more useful it is to identify a suspect
Why are fibers used to reconstruct crime scenes?
- condition of the garment/fiber - type and composition of the fabric - mobility of victim - length of time between actual and physical contact
What are fibers?
- considered class evidence - have probative value - common trace evidence at a crime scene - can be characterized based on comparison of both physical and chemical properties
Why are prints unique?
- due to the way they are formed - randomly grown while in the womb - friction and pressure on the areas where ridges form affect their final outcome
What are individual characteristics of fibers?
- high probability of linkage with only one individual - one of a kind, unusually made fiber made in very small amount with unusual dye
What are the tests for identification?
- microscope observation - burning - thermal decomposition - chemical tests - density - refractive index - fluorescence
What are the basic comparisons of fiber samples?
- microscopic comparison of color and diameter - lengthwise striations - cross-section of fiber (shape) - fabric comparisons (weave pattern, thread count) - color separation
What are the types of synthetic fibers?
- rayon - nylon - acetate - acrylic - spandex - polyester (Under Armor) - polypropylene (bicycling clothing) - kevlar - lycra
What are the types of natural fibers?
- silk - linen - angora - cotton - wool - mohair - cashmere - hemp - all furs
What is the value of fibers dependent on?
- type of fiber - color or color variations in fiber - location of fiber - number of fibers that matches between victim and suspect
What are the classifications of natural fibers according to their origin?
- vegetable or cellulose - animal or protein - mineral
What are the medical examiner's responsibilities?
1. identify the deceased 2. establish the time and date of death 3. determine the medical cause of death 4. determine the mechanism of death 5. classify the manner of death 6. notify the next of kin
medical examiner responsibilities
1. identify the deceased 2. establish the time and date of death 3. determine the medical cause of death (the injury or disease that resulted in the person dying) 4. determine the mechanism of death (the physiological reason that the person died) 5. classify the manner of death - natural - accidental - suicide - homicide - undetermined 6. notify the next of kin
Types of crimes:
1. infraction- miner offense or petty crime; penalty is usually a fine 2. misdemeanor- minor crime punishable by fine or jail 3. felony- major crime punishable by fines and/or more than one year in prison
Facets of Guilt
1. means- the ability to have committed the crime 2. motive- the reason for committing the crime. (This doesn't have to be proven or presented in a court of law, but its what everyone wants to know) 3. opportunity- time or availability to have committed the crime
How do you collect evidence?
1. photograph 2. markers/labels 3. sketch 4. collect 5. turn in to lab 6. chain of custody receipt
How do you search the scene?
1. record (take notes, photos, and sketch) 2. start at entry/path 3. choose a systematic method 4. glove up
What year did Galton publish Finger Prints?
1892
During what decade did Federal prisons begin to use fingerprints to identify prisoners?
1920's
When did James Watson and Francis Crick discover the DNA double helix?
1959
When was AFIS made?
1977 (fully in the FBI by 1996)
When was Williams convicted?
1982
When were DNA first used in criminal cases?
1984
When was DNA discovered
1990s
When was DNA discovered?
1990s
Murder charges
1st degree murder: premeditated 2nd degree murder: killed intentionally, but not thought out as much ahead of time voluntary manslaughter: usually involves sudden passion (fear, rage, anger, terror) involuntary manslaughter: (criminally negligent homicide) killed someone, but unintentionally
How many centimeters are in a inch?
2.54 centimeters
How many bones are in the body?
206
When do fingerprints come about?
24 weeks in utero
What percent of fingers have whorls?
30%
What amendments are relevant to the Miranda Rights?
4 and 5
How many forensic pathologists are throughout the U.S.?
400
Low velocity of blood
5 feet per second or less
Medium velocity of blood
5 to 25 feet per second
What percent of fingers have arches?
5%
What percent of fingers have loops?
65%
If someone has more than 32 teeth, they are ____
A full adult
If someone has under 20 teeth, they are _____
A young child
What does the first officer on the scene do?
ADAPT
Probative evidence
Actually proves something
Material evidence
Addresses an issue relevant to the particular crime
What can a forensic anthropologist determine?
Age range, sex, race, approximate height, cause of death, disease, or anomaly
What can you determine from bones?
Age, sex, race, approx height, cause of death
Miranda Rights
Amendments 4 and 5 Right to remain silent, right to attorney, right to a fair and just trial, and everything you say may be used in the court of law
Angle of impact
Angle at which blood strikes a target surface
Eye orbits for Whites
Angular
Forensic anthropology
Applied anthropology that specializes in the changes in the human skeleton for the purpose of legal inquiry
Growth of Labs
As populations have grown, forensic science labs have been developed in new areas and older labs have grown in size to reflect the growing population they serve.
First officer on the crime scene does ADAPT
Assess the crime scene and assist the injured Detain the witness Arrest the perpetrator Protect the crime scene Take notes
Epiphyses
At the ends of the bones, function allow for growth - where the growth plate is
What does AFIS stand for?
Automated Fingerprint Identification System
What type of sacrum do females have?
Backward
What happens in the next 10-20 days of death?
Black putrefaction, creamy flesh, exposed body parts are black, body collapse as gases and fluids drain
Pathology unit
Blood
Algor mortis
Blood cooling rate
Physical science units
Chemistry, physics, geology
Who used fingerprints as a signature on documents?
Chinese
What type of ilia do males have?
Close
CODIS
Combined DNA Index System
What does RFLP do?
Cut DNA into smaller fragments that can be separated and characterized
Biology unit
DNA, blood, body fluid
What happens in the first 0-4 days of death?
Decomposing internally, initial or fresh decay
Odontology unit
Dentist/teeth
How do you determine age and stature?
Determined by analyzing the development of the teeth, bone growth, cranial suture lines, and the length of specific bones, such as the femur
How do you determine race?
Determined by analyzing the skull for characteristics that are common among people of different races
How do you determine sex?
Determined by examining the skull, pelvis, humerus, and femur
Expert Witness
Determined by.... - Education - Experience - Training - Certification - Demeanor
Who paid a doctor to change his prints by cutting squares out of his prints then turned them upside down and sewed them back on?
Donald Roquierre
What type of container is trace evidence stored?
Druggist fold with container that allows no leakage
Toxicology unit
Drugs
_____ prints are lifted with 1 ½ -2 inch wide clear tape and placed onto a piece of _____.
Dusted, cardstock
Coroner
Elected official with no medical training
14th Century Chinese
Forensic Medicine was around
Forensic Anthropology
Forensic anthropology is a type of applied anthropology that specializes in the changes and variations in the human skeleton for the purpose of legal inquiry
What is forensic science?
Forensic science is the scientific study of evidence to discover the facts in a criminal or civil matter. The science applied to solve crimes.
What type of sacrum do males have?
Forward
Who was the first person to study fingerprints and develop a system of classifying?
Galton
Growth of Labs
Generally - population Other Factors - Miranda? - 1960's? - Technology
What does a cortex do with hair?
Gives it its shape
High velocity of blood
Greater than 25 feet per second
What type of pubic angles do females have?
Greater than 90 degrees
Cause
HOW
Race characteristics of white people
Have a long, narrow nasal aperture, a triangular palate, oval orbits, narrow zygomatic arches, and narrow mandibles
Race characteristics of asians
Have a more rounded nasal aperture, a parabolic palate, rounded orbits, wide zygomatic arches, and more pointed mandibles
Race characteristics of black people
Have a wide nasal aperture, a rectangular palate, square orbits, and more pronounced zygomatic arches. The long bones are longer, and have less curvature and greater density
White
High zygomatic arch
What are examples of long bones?
Humerus, tibia
What other information can law enforcement agencies require for the labeling of evidence?
ID or badge number, victim's name and address (if known), district of occurence
What is DNA profiling used for?
Identifying suspects, free individuals, identity victims, establish paternity, match organ donors
Growth plate
If there's a gap between bones, you're still growing. If there is no gap, you're done growing
federal rules of evidence
In order for scientific evidence to be admitted in a court of law, it must be: 1. Probative: actually proves something 2. Material: addresses an issue that is relevant to the particular crime
Cortex of hair
Inner layer made of keratin and embedded with pigment
Medulla
Inside layer of hair running down the center of the cortex
White progmatisim
Jaw and nose line up perfectly
Black progmatisim
Jaw juts out
Who paid a doctor $5000 to change his face and "remove" his fingerprints by putting acid on his fingers?
John Dillinger
Daubert court case
Judges decide if evidence can be admitted by whether the theory can be tested, whether the science has been offered for peer review, whether the rate of error is accepted, method is wide spread, or the theory follows standards
What type of mastoid process do males have?
Large
What type of pelvic outlet do females have?
Large
What type of pubic angles do males have?
Less than 90 degrees
What does CODIS do?
Links serial crimes and unsolved cases with repeat offenders
Edmund Locard
Locard's Principal of Exchange- the perpetrator of a crime will bring something into the crime scene and leave with something from it, and that both can be used as forensic evidence
Edmund Locard
Locard's Principle of Exchange
What's the best bone to determine height?
Long bone
What kind of bone is used to determine age?
Long bone (humerus, tibia) or skull or teeth
What does PCR do?
Make copies of a defined segment of a DNA molecule
Medical examiner
Medical doctor, appointed by the gov of the area
What gives hair its color?
Melanin
_____ doesn't have to be proven or presented in a court of law, but its what everyone wants to know.
Motive
Manner
Natural, homicide, suicide, accident, undetermined
What are chemical substances to develop a print?
Ninhydrin, Iodine, Silver Nitrate, Genetian Violet, Super Glue
What is DNA composed of?
Nucleotides
Ware and tear on the bones, what does that mean?
Older
What are the types of carpet fibers?
Orlon, Dacron
Cuticle of hair
Outside covering made of overlapping scales
Any suture that is completely closed they are usually
Over 30 (but in women sometimes over 50)
What's the best bone to determine sex?
Pelvis, could also use skull
Palynology unit
Pollen spores
PCR
Polymerase chain reaction
Set-ups of Labs
Possible sections in a lab - Biology/DNA - Chemistry/Drug?- Toxicoloy - Arson/Explosives (not always) - Firearms/Toolmarks - Trace (not always ) - Questioned Docs (not always) - Polygraph, voice Detection (not always) - Medical Examiner (usually a separate office)
Ventral arc
Present in females, front arc in the pubic bone
What type of brow ridges do males have?
Prominent
What happens in the next 4-10 days of death?
Putrefaction or bloating - cadaver is swollen by gas produced internally
What type of forehead do males have?
Receding
Asian progmatisim
Receding jaw
Eye orbits for Blacks
Rectangular
Rigor mortis
Rigidity of skeletal msucles
Who hired a doctor to remove his fingerprints then graft abdominal skin onto his fingers?
Roscoe Pitts
Eye orbits for Asians
Round
What type of chin do females have?
Rounded
Who taught law enforcement agencies how to use fingerprints at the 1904 World's Fair in St. Louis?
Scotland Yard
Arthur Conan Doyle
Sherlock Holmes novels
Livor mortis
Skin discoloration caused by pooling of blood
What's the best bone to determine race?
Skull
What type of brow ridges do females have?
Slight
What type of mastoid process do females have?
Small
What type of pelvic outlet do males have?
Small
What type of ilia do females have?
Spread
What type of chin do males have?
Square
Who was the first in the United States to use fingerprinting for identification?
St. Louis City Police
Transient evidence
Temporary, usually observed by the first officer at the scene
What was the result of the Frye v. United States (1923) case?
The Frye Standard (evidence, procedures, and equipment presented at trial must be generally accepted by the scientific community)
Zygomatic Arch
The bony arch of the cheek formed by connection of the zygomatic and temporal bones.
What was the result of the Dr. Carl Coppolino (1963) case?
The court ruled: - the fact that a technique, test, or procedure is new does not necessarily mean its findings are inadmissible in court - the expert witness is responsible for providing scientifically valid testimony to support the findings
Frye court case
The evidence presented in the trail and jury and decides if it can be used if it is generally accepted by the scientific community
Serology
The examination and analysis of blood fluids
What part of the hair has mitochondrial DNA?
The hair shaft
Why do investigators use an age range?
The investigator doesn't want to eliminate any possibilities for identification
If the skull sutures are closed, what does that mean?
The person is older
If the skull sutures are opened, what does that mean?
The person is younger
What part of the hair has nuclear DNA?
The root
Diaphysis
The shaft of the long bone
What is the tibia also known as?
The shin bone
Osteology
The study of bone
How can you estimate the weight of a person?
The ware and tear of the bones
Ware and tear on particular side of the body?
They possibly were right/left handed, or used that side more
What is a double helix?
Two coiled DNA strands
What was the result of the Daubert v. Merrell Dow Pharmaceuticals (1993) case?
U.S. Supreme Court ruled that the trial judge had ultimate decision-making power regarding expert testimony at trial
Any suture that is completely open they are usually
Under 25
What type of forehead do females have?
Vertical
Mechanism
WHY BODY STOPPED
In what case did fibers weigh heavily on the outcome of the case?
Wayne Williams
Testimonial evidence
What is said in court by a competent witness
Locard's Principle of Exchange
When two objects come in contact, there is always something left behind.
Female has a _____ subpubic concavity or subpubic angle
Wide
Black
Wide zygomatic arch
Female has a ____ public body than a male
Wider
forensic pathology
a field in which the principles of medicine and pathology are applied to determine a cause of death or injury in the context of a legal inquiry
forensic psychology
a field in which the principles of medicine and pathology are applied to determine a cause of death or injury in the context of a legal inquiry
Who is a medical examiner?
a medical doctor, usually a pathologist, and is appointed by the governing body of the area
What does the sixth amendment ensure?
a person will be tried by an impartial jury of his or her peers
What is a plain whorl like?
a spiral
What is fluorescence?
absorption and reemission of light; used for comparing fibers as well as spotting fibers for collection
What do nonporous containers like mason jars and metal cans that seal prevent?
accelerants from arson scenes from evaporating from the containers
How can fingerprints be destroyed?
acid, grafting skin, surgically removing skin, burning
What is probative evidence?
actually proves something
What is material evidence?
addresses an issue that is relevant to the particular crime
What should you sketch about the scene?
all evidence found, measurements (two from fixed points), orientation and direction (North directional marker), labels for representing evidence
How is the fiber from a scene compared to fiber from a known source?
all the characteristics found on the known fiber and the questioned fiber must be identical
forensic podiatry
an application of the study of feet, footprint, or footwear and their traces to analyze scene of crime and to establish personal identity in forensic examinations
Who is a coroner?
an elected official who usually has no special medical training; in 4 states, the coroner is a medical doctor
What is wool?
animal fiber coming most often from sheep, but may be goat (mohair), rabbit (angora), camel, alpaca, llama, vicuna
What is a natural fiber?
animal, vegetable, or inorganic
forensic document examination or questioned document examination
answers questions about about a disputed document using a variety of scientific processes and methods. Many examinations involve a comparison of the questioned document, or components of the document, with a set of known standards. The most common type of examination involves handwriting, whereby the examiner tries to address concerns about potential authorship.
Alphonse Bertillon
anthropometry (science that would measure the arms and lengths of men to identify criminals)
What do containers need to be in order to prevent loss or damage?
appropriate size, appropriate type
What does the second A in ADAPT stand for?
arrest the perpetrator
What does the A in ADAPT stand for?
assess the crime scene and assist the injured
For how many years have fingerprints been used for many purposes?
at least 3000 years
Describe a tented arch.
at least one ridge forms a line straight up like a tent pole
When do you release the crime scene?
at reasonable time, after check walk through, after recording "released to..." and "date/time", and after getting a warrant
When hairs and fibers are lifted from a surface using tape, the tape can be _____.
attached to a petri dish and the dish can be contained in an envelope
What is FTIR?
based on selective absorption of wavelengths of light
What is cotton's value in forensic investigations?
basically meaningless
Each piece of evidence should _____.
be photographed, have its location marked, be measured for location in a sketch, be properly collected, and have a record of chain of custody
Why are fibers class evidence?
because of mass production of goods/garments
When is the discovery phase?
before the trial
What are the seven ridge characteristics?
bifurcation, enclosure, ridge ending, island or dot, ridge crossing, short ridge, spur
What are the classifications of evidence by nature?
biological, chemical, physical, miscellaneous
What are the possible sections in a lab?
biology/DNA, chemistry/drug?, toxicology, arson/explosives (not always), firearms/toolmarks, trace (not always), arson/explosives (not always), questioned documents (not always), polygraph, voice detection (not always), medical examiner (usually a separate office)
What are examples of pattern evidence?
blood spatter, glass fracture, fire burn pattern, furniture position, projectile trajectory, tire marks or skid marks, clothing or article distribution, gunpowder residue, material damage, body position, toolmarks, modus operandi
What is biological evidence?
blood, semen, saliva, sweat, tears, hair, bone, tissues, urine, feces, animal material, insects, bacteria, fungi, botanical material
What do rigid containers protect evidence from?
breakage and scratching
What is PGC-MS?
burns a sample under controlled conditions, separates and analyzes each combustion product
How are knitted fabrics made?
by interlocking loops into a specific arrangement
How are prints collected?
by rolling each print in ink or scanning them
How do you prevent metals from being bent or scratched?
by wrapping in cotton and placing in rigid containers
How do you prevent fragile evidence from being broken?
by wrapping it in cotton and placing in a rigid container
Individual characteristic
can be identified with a particular person or a single source
What is individual evidence?
can be identified with a particular person or a single source (fingerprints, blood DNA typing, etc.)
If any part of the chain of custody record is missing or questioned, the evidence _____.
can be inadmissible (useless) in court
What is the second significance of fiber evidence?
can prove contact between an individual and an object
What is the first significance of fiber evidence?
can prove contact between two individuals
What was his conviction based on?
carpet fibers that were found in his home, car and on several murder victims
What is cellulose acetate?
cellulose chemically-altered to create an entirely new compound not found in nature
What does the design of plain weave resemble?
checkboard
What is rayon?
chemically-altered cellulose; soft, lustrous, versatile
What is used to separate dyes for comparative analysis?
chromatography
Comparison of _____ . If all measurements are equal, then the two samples may be considered to have come from the same source or origin.
class characteristics measured against those of known standards or controls
What does it mean to say fiber from a scene and fiber from a known source are similar fibers?
class or individual
Paul Kirk
coined term forensic science
Each piece of evidence, even if it is the same type (e.g. 3 of the same type of .357 caliber cartridge cases) are _____.
collected in separate containers
Preservation though the _____.
collection and proper packaging of evidence
What is the minimum amount of things needed when labeling collected prints?
collector's name, date and time of lift, location of the lift
Conditional evidence fire?
color and direction of the flames, speed of spread, temperature and condition of fire
Conditional evidence smoke?
color, direction of travel, density, odor
Class characteristic
common to a group of objects or persons
What is class evidence?
common to a group of objects or persons
Conditional evidence scene?
condition of furniture, doors and windows, any disturbance or signs of a struggle
What are class characteristics of fibers?
consistent with a group
A forensic scientist can only say that two fibers are what?
consistent with each other
What is yarn?
continuous strand of fibers or filaments, either twisted or not
Loops may be one _____ thread or a _____.
continuous, combination
What is a very common fiber?
cotton
Hans Gross
criminalistics
involuntary manslaughter
criminally negligent homicide (killed someone, but unintentionally)
Daubert
criteria for evaluating the science used to support evidence presented by an expert
What do you takes notes over when you are at the crime scene?
date/time of arrival, name, address/description, weather conditions, log of all activities
forensic entomology
deals with the examination of insects in, on and around human remains to assist in determination of time or location of death. It is also possible to determine if the body was moved after death.
Likelihood of finding transferred fibers on the clothing of the suspect _____ after each day that passes.
decreases
What are the individual qualities of the different fabrics?
degree of: - stretch - absorbency - water repellence - softness - durability
Individualization in _____.
demonstrating that the sample is unique, even among members of the same class
What is one of the most common examples of twill weave?
denim
What does the D in ADAPT stand for?
detain the witness
Fingerprints are chemically _____ and _____.
developed, photographed
What weave pattern does twill weave make?
diagonal weave pattern
What do you have to make sure when collecting fiber evidence?
different items are not placed on the same surface before being bagged
By varying the chemical structure of the monomers or by varying the way they are joined together, polymers are created that have _____ _____.
different properties
What is quadrant/one-search?
divides an area into sections that are small enough to be searched by one person
What does a CSI unit do?
documents the crime scene in detail and collects any physical evidence
Conditional evidence vehicles?
doors locked or unlocked, windows opened or closed, radio off or on, odometer mileage
What are expert witnesses determined by?
education, experience, training, certification, demeanor
What is the expert witness determined by?
education, experience, training, certification, demeanor
What are the accepted standards for most agencies?
eight points
What do paper containers collect (paper bags, cardboard boxes and sheets of paper) ?
evidence that contains body fluids
What is spandex?
extreme elastic properties
What is blend?
fabric made up of two or more different types of fibers
T/F When someone is being arrested in the area they are in (home/car/etc.) they cannot be searched.
false
T/F You cannot search without a warrant if consent is given by the parties involved.
false
T/F You do not wear gloves when at the crime scene.
false
True or False - A fingerprint does not remain unchanged during an individual's lifetime.
false
True or False - The holes of the nozzle are round.
false - not necessarily round
What are latent prints made up of?
fatty acids, oils, amino acids, proteins, salts, H20
What is fabric made of?
fibers
What is chemical evidence?
fibers, glass, soil, gunpowder, metals, minerals, narcotics, drugs, paper, ink, cosmetics, paint, plastic, lubricants, fertilizer
William Herschel
fingerprint
What is the most common way to visualize latent prints?
fingerprint powder and brush
What is physical evidence?
fingerprints, footprints, shoeprints, handwriting, firearms, tire marks, toolmarks, typewriting
What are examples of imprints and indentations?
footprints, teeth marks in perishable foods, tire marks on certain surfaces
What happens when synthetic fibers are hot?
forced out of a nozzle then woven
What are the other areas of forensic science?
forensic art, forensic psychiatry, forensic odontology, forensic pathology, forensic engineering, computer forensic, jurisprudence
14th century Chinese
forensic medicine
How many types of whorls are there?
four
How are fingerprints made?
from movements in the womb
How should you measure each piece of evidence?
from two fixed points or using triangulation
What is the arrest phase?
gathering evidence to show probable cause (observation, expertise, information, circumstantial evidence)
What is thermal decomposition?
gently heating to break down the fiber to the basic monomers
What is interpretation?
giving meaning to all the information
What do you do in the collection of evidence?
glove up, use separate containers, label outside of containers, seal the containers
What do fingerprints help us do?
grab objects
What do you collect from the body?
hair and fiber; clothing; blood sample; bullets; fingernail scrapings; oral, anal, and vaginal swabs in sexual assaults; organ samples for possible testing
Describe a double loop whorl?
has two loops, one upside down next to the other
Conditional evidence light?
headlight, lighting conditions, lights on or off
The way a fabric accepts a particular dye may also be used to do what?
identify and compare samples
What is pattern evidence mostly in the form of?
imprints, indentations, striations, markings, fractures, or deposits
In fabric production, what are fabrics composed of?
individual threads or yarns, made of fibers, that are knitted, woven, bonded, crocheted, felted, knotted or laminated
What are the evidence characteristics?
individual, class
How do you bag clothing items?
individually in paper bags
Reconstruction of the events in the case using _____.
inductive and deductive logic, statistical data, pattern analysis, results of laboratory analysis
Types of Crimes
infraction, misdemeanor, felony
What should be directly written on the seal after covering the opening of the container?
initials of the person sealing the evidence, date sealed
What is silk?
insect fiber that is spun by a silk worm to make its cocoon; fiber reflects light and has insulating properties
2nd degree murder
killed intentionally, but not thought out as much ahead of time
What is miscellaneous evidence?
laundry marks, voice analysis, polygraph, photography, stress evaluation, psycholinguistic analysis, vehicle identification
Where do forensic scientists work?
law enforcement agencies, forensic labs, universities, hospitals, consulting offices
What are examples of conditional evidence?
light, smoke, fire, location, vehicles, body, scene
What is a line search?
line up searchers within arm's-length of one another and forms a line that walks across the scene
What are the types of searches?
line, strip, grid, link, zone, wheel/ray, contracting spiral, expanding spiral
Describe a plain arch.
lines go all the way across the print
What do the bottom of ulnar loops point out toward?
little-finger-side of the hand
What are polymers?
long chains of repeating chemical units
What does satin weave create?
long floats
How do you determine if a print from a scene is consistent with a control from a suspect?
look for points to see if they have the same ridge characteristics
What do zip-closure containers prevent?
loss of trace evidence
What is a felony?
major crime punishable by fines and/or more than one year in prison
How do you lift fiber evidence?
make tape lifts of exposed skin areas of bodies and any inanimate objects
What is fiberglass?
manufactured inorganic fiber
What is rock wool?
manufactured mineral fiber
What does the word polymer mean?
many (poly) units (mer)
What is density?
mass of object divided by the volume of the object
Facets of guilt
means, motive, opportunity
What is refractive index?
measurement of the bending of light as it passes from air into a solid or liquid
What is a misdemeanor?
minor crime punishable by fine or jail
What is an infraction?
minor offense or petty crime; penalty is usually a fine
What are the repeating units of a polymer called?
monomers
How many different dye formulations are there?
more than 7000
What is nylon?
most durable of man-made fibers; extremely light weight
What is polyester?
most widely used man-made fiber
What is placed on the outside of a container?
name of collector, date and time collected, brief description of the evidence
What are the types of fibers and fabric?
natural and artificial
What is asbestos?
natural fiber that has been used in fire-resistant substances
What is manner?
natural, accidental, suicide, homicide, undetermined
Do you simplify fractions with Henry Number?
no (police math)
How many deltas do arches have?
none
What type of container is arson evidence stored?
nonporous and unbreakable container
What is burning?
observation of how a fiber burns, the odor, color of flame, smoke and the appearance of the residue
What is secondary transfer?
occurs when already transferred fibers on the clothing of a suspect transfers to clothing of a victim
What is primary transfer?
occurs when fibers are transferred from a fabric directly onto a victim's clothing
What are examples of transient evidence?
odor, temperature, imprints, and indentations
Conditional evidence location?
of injuries or wounds, of bloodstains, of the victim's vehicle, of weapons or cartridge cases, of broken glass
How many deltas do loops have?
one
What makes our fingerprints individual?
our ridge patterns and how those patterns were created in utero
Interlacing weave of satin pass _____ _____ or more yarns.
over four
The warp yearn of twill weave is passed _____ _____ to _____ weft yarns before going _____ one.
over one, three, under
What should you photograph?
overview (shows as much of the scene as possible), rooms or areas near the scene, possible entry/exit paths, physical evidence, close-ups of each piece of evidence so that piece of evidence is in the photo, and perspective of that piece of evidence located in the scene
What should fibers be stored in?
paper bag
Identification using scientific testing of _____.
physical properties, chemical properties, morphological (structural) properties, biological properties, immunological properties
What is the simplest and most common weave pattern?
plain weave
What are synthetic fiber made of?
polymers
What container type are body fluids stored?
porous container
Conditional evidence body?
position and types of wounds; rigor, livor, and algor mortis
1st degree murder
premeditated
What is important for the reconstruction of crime scene?
primary and secondary transfer
In order for scientific evidence to be admitted in a court of law it must be _____ or _____.
probative, material
What is conditional evidence?
produced by a specific event or action; important in crime scene reconstruction and in determining the set of circumstances or sequence within a particular event
What is transfer evidence?
produced by contact between person(s) and object(s), or between person(s) and person(s)
What is pattern evidence?
produced by direct contact between a person and an object or between two objects
What happens at the trial?
prosecution and defense present their cases
What does the P in ADAPT stand for?
protect the crime scene
What is acrylic?
provides warmth from a lightweight, soft and resilient fiber
What are examples of odor?
putrefaction, perfume, gasoline, urine, burning, explosives, cigarette or cigar smoke
What are the typical search methods?
quadrant or one-search
What seven things happen in forensic investigations?
recognition, preservation, identification, comparison, individualization, interpretation, reconstruction
RFLP
restriction fragment length polymorphism
Fingerprints have general characteristic _____ that permit them to be systematically classified.
ridge patterns
What are the Miranda Rights?
right to remain silent, right to attorney, right to a fair and just trial, anything you say may be used in the court of law
What container type are glass or other breakables stored?
rigid container
What container type are metal objects stored?
rigid container
What do deltas look like?
river deltas
Yarn is formed into successive _____ of _____ then drawn through another _____ of loops to make the fabric.
rows, loops, series
All prints with same number are stored where?
same section of files
What is the most obvious example of satin weave?
satin
Frye
science had to be accepted
What is a spiral search?
searches inward from the piece of evidence farthest from the center of the scene in a spiral motion until the center is reached or begins at the center of the evidence and searches outward in a spiraling motion
What is a grid search?
searches the scene going back and forth in one direction until you reach the opposite side of the scene, then searches perpendicular to that direction, back and forth until the entire area is covered
Components that make up dyes can be _____ and _____ to an _____.
separated, matched, unknown
STR
short tandem repeats
What should removed fibers be folded into?
small sheet of paper
What are chemical tests?
solubility and decomposition
What is an accidental whorl?
some combination of print types
What is associative evidence?
something that may associate a victim or suspect with a scene or with each other; e.g., personal belongings
What does the design of twill weave resemble?
stair steps
What are examples of temperature?
surroundings, car hood, coffee, water in a bathtub, cadaver
What do invisible (latent) prints leave?
sweat and oils from skin on a surface
What is an artificial fiber?
synthesized or created from altered natural sources
What does the T in ADAPT stand for?
take notes
Forensic DNA analysis
takes advantage of the uniqueness of an individual's DNA to answer forensic questions such as paternity/maternity testing and placing a suspect at a crime scene, e.g. in a rape investigation
How do you secure the crime scene?
tape off area large enough to contain all possible evidence (within reason)
What is transient evidence?
temporary; easily changed or lost; usually observed by the first officer at the scene
What is means?
the ability of having committed the crime
What is recognition?
the ability to distinguish important evidence from unrelated material; pattern recognition; physical property observation; information analysis; field testing
trace evidence analysis
the analysis and comparison of trace evidence including glass, paint, fibers, and hair
forensic anthropology
the application of physical anthropology in a legal setting, usually for the recovery and identification of skeletonized human remains
criminalistics
the application of various sciences to answer questions relating to examinations and comparison of biological evidence, trace evidence, impression evidence (such as fingerprints, footwear impressions, and tire tracks), controlled substances, ballistics, firearm and toolmark examination, and other evidence in criminal investigations. In typical circumstances evidence is processed in a Crime lab.
What is AFIS?
the computerized system that compares fingerprints to the millions of prints in the FBI database
What do porous containers allow for?
the evaporation of water which prevents body fluids from molding
What happens because the holes of the nozzle are not necessarily round?
the fiber may have a unique shape in cross-section
Terminal velocity
the greatest speed to which a free-falling drop of blood can accelerate in air. It is dependent upon the acceleration of gravity and the friction of the air against the blood
What is cause?
the injury or disease that resulted in the person dying
Who does the body belong to?
the medical examiner's office
What is mechanism?
the physiological reason that the person died
What is motive?
the reason for committing the crime
What is chain of custody?
the record of all that happens to the evidence from the moment it is discovered until the case is closed (found not guilty or served the sentence and released) and the evidence is destroyed
forensic engineering
the scientific examination and analysis of structures and products relating to their failure or cause of damage
What is forensic science?
the scientific study of evidence to discover the facts in a criminal or civil matter, or the science applied to solve crimes
forensic serology
the study of body fluids
forensic chemistry
the study of detection and identification of illicit drugs, accelerants used in arson cases, explosive and gunshot residue.
forensic dactyloscopy
the study of fingerprints
forensic toxicology
the study of the effect of drugs and poisons on/in the human body
forensic odontology
the study of the uniqueness of dentition, better known as the study of teeth.
The medical examiner collects evidence from the body unless _____. They also collect any foreign objects found during the autopsy (broken knife tips, balloons filled with drugs) and swabs of the hands in cases in which firearms are involved.
there is danger of losing the evidence before they can collect it
As a result of differences in polymers, what happens forensically?
they can be distinguished from one another
What do the bottom of radial loops point out toward?
thumb-side of the hand
What is opportunity?
time or availability to have committed the crime
How can fiber evidence in court cases be used?
to connect the suspect to the victim or to the crime scene
Why is it important to take detailed notes?
to have an accurate sketch to facilitate your recall of the work you have done, to remember that all you may be called to testify about this scene years later
Why do you secure the crime scene?
to keep others out, to prevent alteration and destruction
The search is the only way _____.
to prevent immediate loss of evidence (drugs are in danger of being flushed down the drain)
In order to obtain a search warrant from a judge, you must be able _____.
to show probable cause
What are visible prints?
touching a colored liquid, then leaving it on a surface
What are plastic prints?
touching a soft surface that will mold to your ridge characteristics
Orfila and Raspil
toxicology
What are the types of physical evidence?
transient evidence, pattern evidence, conditional evidence, transfer evidence, associative evidence
T/F If people have been injured or blood is found at the scene, you can search for injured parties in order to provide aid.
true
T/F You change the gloves between pieces of evidence.
true
True or False - A fingerprint is an individual characteristic.
true
True or False - Deltas can be used to determine if a print is a loop, whorl or arch.
true
True or False - It would take very unusual circumstances to be able to say that fibers had individual characteristics.
true
True or False - Most fabrics are either woven or knitted.
true
How many points do the FBI require?
twelve
What are fibers made of?
twisted filaments
How many deltas do whorls have?
two
Describe a central pocket loop whorl?
ulnar or radial loop with a spiral in the center
What must control samples of fibers be?
uncontaminated, large enough to do testing needed
The warp and weft yarns of plain weave pass _____ each other _____.
under, alternately
For satin weave, the yarn interlacing is not _____.
uniform
What is optical microscopy?
uses polarizing light and comparison microscopes
voluntary manslaughter
usually involves sudden passion (fear, rage, anger, terror)
What is the third value of fiber evidence?
value is dependent
What is cotton?
vegetable fiber; strong, tough, flexible, moisture absorbent, not shape retentive
Where do control samples of fibers come from?
victims and suspects' homes and vehicles
What is the difference between warp and weft?
warp - lengthwise yarn weft - crosswise yarn
What in chain of custody?
what testing was done to it
When in chain of custody?
when they had it
Where in chain of custody?
where was it stored
Who in chain of custody?
who had the evidence at all times
What is the Henry Number based on?
whorls and type of finger
The more movement, the more likely fibers _____ _____ _____.
will be transferred
