Chapter 6 – Forensic Serology

Protein in the red blood cells containing heme groups, is what?

Two types of Blood Evidence:

∙ Blood biochemistry analysis

∙ Pattern analysis

*Blood = mixture of cells and plasma

∙ Red blood cells (RBCs), white blood cells (WBCs) and platelets  ∙ RBCs float in plasma  

*plasma= liquid portion of the blood containing electrolytes, nutrients,  waste products, vitamins, hormones, …. And antibodies to fight infection  

Plasma  

∙ Clear, yellowish fluid (the color of straw)  

∙ Will be milky after fatty meal

∙ 90% water 10% protein

∙ blood serum – blood that is allowed to clot then gets filtered and  has no clotting factors

 Red Blood Cells  

∙ Erythrocytes *most abdundant

∙ The percentage of blood made up of RBCs is frequently measured  and is called the hematocrit  

o Ratio of cells in normal blood is 600 RBS for each white blood  cell and 40 platelets

What hemoglobin has that accelerate oxidation of organic compounds?

o If you get injured this number will go down

o And tries to replace the fluid by drawing water out your cells  – and at some point your blood volume drops too much and  that’s not good

o To determine internal bleeding : look at hematocrit  

 Uniqueness of RBCs  

∙ An RBC has no nucleus – when the cell matures it is extruded o They have a limited lifetime because of this

∙ Shape: A biconcave disc, round and flat like a shallow bowl  ∙ They can change shape to squeeze through capillaries in a single  file  

∙ An RBC contains hemoglobin, a molecule specially designed to  hold oxygen and carry it to cell that needs it  

 White Blood Cell and Platelets  

∙ WBC are leukocytes

o Part of the immune system and fight infection  

o If you’re wondering if you’re sick and you end up having more  white blood cells – then you probably sick  

What is the liquid portion of the blood containing electrolytes, nutrients, waste products, vitamins, hormones?

∙ Platelets (thrombocytes) help blood clot by forming a platelet plug, so it explodes and almost glues the blood cells together to stop the  bleeding  We also discuss several other topics like What is Science?

 Blood Chemistry  

∙ Hemoglobin – Protein in the red blood cells containing heme groups  

o Heme – iron (where we stick oxygen)  

∙ Blood is always RED (not blue),just different shades of red  ∙ Blood in arteries – oxygen rich from lungs (really dark red)

∙ Blood in veins – oxygen poor

 Blood Types

∙ Karl Landsteiner, 1900

o Noted that when blood from different people is mixed it  sometimes forms precipitate – deadly if mixed in body.  

Explored why  

∙ Based on what protein is present  

o Type O – 2 H antigen  

 Has antibodies to everything  

o Type A – ( 2 A antigen or 1 A antigen and an H antigen)   You have b antibodies  

o Type B – (2 B antigen or 1 B antigen and an H antigen )   You have a antibodies  

o Type AB –(both A and B antigens)  

 Cant have antibodes – neither A nor B  

o Antibodies are weapons against the other blood types  ∙ Most common types  Don't forget about the age old question of what is Psychosocial crisis?

o O+ and A+ are most popular  

o Type O – universal donor because it can be given to  

anybody ; it has no proteins on the outside to cause clumps  (coagulation)  

o Type AB – universal receiver because the recipient has all of  the proteins so wont form clumps (coagulation  

∙ Agglutination – the antibodies glue together to antigens from  different red cells thereby sticking the red cells together forming  “islands”  

o Blood remains liquid

o In clotting it doesn’t remain liquied  

 Blood Clots  

∙ Result of injury to blood vessel - the loss of blood has to be stopped before shock and possible death If you want to learn more check out Whenever you can ask “IN WHAT DIRECTION?

o So, we solidify the blood – coagulation or clotting  

∙ Blood clot :

o A plug of platelets enmeshed in  

o a network of insoluble fibrin molecules  

∙ inactivated platelets are smooth and when activated they turn spiky

 Blood Type Genetics  

Three forms of the gene (alleles) that control the ABO blood group,  designated as iA, iB, and i.  

Two alleles (one from the mother and one from the father) form a  persons genotype.  

The inheritance of the alleles is co-dominant –

∙ if the allele is present, it gets expressed. The following genotypes  will yield these blood types:  

iAiA or iAi - Both genotypes produce the A protein (type A).  iBiB or iBi - Both genotypes produce the B protein (type B).  iAiB- This genotype produces the A and B protein (type AB).  ii - This genotype produces no protein (type O).  

Blood type does not necessarily tell you which alleles you have. It is  possible for two parents with the same blood type (A or B) to have a child  with type O blood. Both parents would have to have a mixed genotype, such  as one i allele together with either one iA or one iB allele. If you want to learn more check out What is Ribosome?

Paternity

And the Father Is:

If  

the  

Mom is:

A

B

AB

O

A

A or O

A, B, AB, or O

A, B,  

or AB

A  

or O

B

A, B, AB or

O

B or O

A, B,  

or AB

B  

or O

AB

A, B, or AB

A, B or AB

A, B,  Don't forget about the age old question of What happens when certain diseases cause demyelination?

or AB

A  

or B

he  

Chil

Mu

Be:

A or O B or O A or  

O

O

B  

Blood (RBC) Diseases

∙ Sickle Cell vs Normal RBC – sickle cell in a diff shape ∙ Trypanosoma brucei protozoa – African cause of Sleeping sickness  ∙ HIV – (causes AIDS) – infected white blood

Immunoassay – a technique utilizing antibodies to bind specifically to  targeted substances in a specimen in order to identify their presence.  ∙ Antibody – proteins produced by immune system to presence of  specific antigen

∙ Antigen – substance that triggers immune response resulting in  antibody (defense against infection and disease!)

Forensic Blood Analysis

∙ Blood ID (“is it blood”?)

o Hemoglobin has enzymes that accelerate oxidation of organic  compounds  

 Bensidine color test - previously used but dropped  

due to carcinogenic reagents

 Kastle Meyer Test – uses phenolphthalein. Blood,  phenolphthalein+H2O2 = deep pink color

 Can give false positives (horseradish, veggies,  

potatoes)

 Luminol Test – Rx pf luminol w/blood produces a  

complex which can be seen by luminescence.  

∙ Blood orgin (human or other source)

o Precipitin test – when animals are injected w/ human blood  they form antibodies to the human blood. Can isolate human  antiserum(antibodies to human blood)  

 Antiserum only reacts with the human blood We also discuss several other topics like what is climate movement?

 Works on old(dried for many years) and small samples  of blood.  

∙ Blood Type  

o ABO and Rh testing  

o Additional blood groupings

o Enzyme presence (many possible enzymes can be determined that are genetically controlled).  

∙ Blood Spatter Analysis- the examination of the shapes, locations, and distribution patterns of bloodstains, in order to provide an  interpretation of the physical events which gave rise to their origin. o Bloodstain Pattern Analysis can be used to:

 Confirm or refute assumptions concerning events  and their sequence: Position of victim (standing,  

sitting, lying). Evidence of a struggle. (blood smears,  blood trails)

 Confirm or refute statements made by principals  in the case: Are stain patterns on a suspects clothing  consistent with his reported actions? Are stain patterns  on a victim or at a scene consistent with accounts given by witnesses or the suspect

Liquid blood

∙ Physical properties

o Viscosity

o Surface tension - res

o Specific gravity  

∙ Behaves as a projectile in motion

o Biology, physics, math

Blood stains  

Passive Projected Transfer

Passive Bloodstains – drops created by gravity  

∙ Smooth – struck on smooth surface

∙ Linoleum – on flooring that’s linoleum has some distorting around  edges

∙ Concrete – striking wood or concrete – distorted to larger extent.  

Spatter Terminology  

∙ Angle of Impact –

o The acute angle formed between the direction of a blood drop and the plane of the surface that it strikes.  

∙ Back Spatter –

o Blood directed back towards the source of energy or force  that caused the spatter.

∙ Forward Spatter –  

o Blood which travels in the same direction as the source of  energy or force which caused the spatter.

∙ Satellite Spatter –  

o Small droplets of blood that are distributed around a drop or  pool of blood as a result of the blood impacting the target  surface.

∙ Spatter –

o That blood which has been dispersed as a result of force  applied to a source of blood. Patterns produced are often  

characteristics of the nature of the forces which created them.

Transfer Bloodstains – created when wet, bloody, surface comes in  contact with another surface

∙ Swipe, smear, wipe, smudge,  

Projected bloodstains – created when a blood source is subjected to  an action greater than the force of gravity  

∙ Size, shape and number of stains depend on the amount of force  utilized to strike the blood source.  

∙ Direction

o When strikes at 90 degree angle = circular  

o At angle less than 90 = elongated or have a tear drop shape

Blood spatter angle  

SIN < = Width (a) 1.5cm

 Length (c) 3.0cm

 Forensic Fingerprint  

∙ Your fingerprint patterns are hereditary  

∙ They are formed before a person is born  

 Fingerprint Basics  

∙ A fingerprint is an individual characteristic

o Not the shape – the #, location, and shape of specific specific  ridge characteristics minutiae

∙ Three basic fingerprint patterns

o Loops, Arches and Whorls  

o Loops most popular – Arches least popular  

o African – arch

o European – loops

∙ Within these patterns are minutia points – about 30 different types  of minutiae points  

 Classification  

∙ Primary Classification  

o Henry (FBI) System – all prints fall into one of 1024 groups  o Automated Fingerprint Ident. Systems  

 Uses automated scanning devices  

Biometrics – identification of humans by measurable physical traits  

Types of Prints  

∙ Latent Prints – invisible to the naked eye and must be developed to  see  

∙ Visible Prints  

∙ Plastic Prints – impressios of fingerprints in soft media

Visualizing Fingerprints  

Important method of detecting latent prints is to dust using a fine  powder that adheres to the traces of oil and sweat  

∙ Aluminum dust  

∙ Carbon black  

∙ Luminescent powders which fluoresce under ultraviolet light  ∙ **dusting is good for hard, not absorbent surfaces, for porous  surfaces like paper or cloth another approach is needed.  

Luminescence  

∙ Excitation of a molecule in absorption of light or as a result of a  chemical reaction  

Visualizing Fingerprints  

∙ Dusting is suitable for hard and/or non-absorbent surfaces.  ∙ For porous surfaces like paper or clothe, chemical treatments are  used  

o Iodine fuming  

o Ninhydrin  

 Colorless compound reacts with amino acids in sweat to  form a colored compound

o Superglue fuming  

Preserving Prints  

∙ Photography (analog and digital imaging)

∙ Lifting with tape (or similar)

 AFIS – Automated fingerprint identification systems ∙ FBI and law enforcement agencies have built up vast collections of  fingerprints  

∙ First classified and compared with filed prints to try and establish a  a match, and therefore to identify a possible suspect  

Hair Fibers and Paint  

Hair  

∙ Appendage of the skin that grows from a follicle

∙ Resitant to chemical decomposition and long term structural  stability  

∙ Can determine  

o Body area where the hair originated  

o Sex of owner

o Sometimes racial origin  

∙ Best identified by examining the medulla & cuticle  

Morphology of Hair  

∙ Cuticle – scales on exterior of hair shaft  

∙ Cortex – main body of shaft, contains pigment granules, shape

∙ Medulla – either absent or not (its like in the middle of the fiber)  o Continuous, interrupted, segmented or absent )

∙ Cuticle and Medulla are best to distinguish is sample is human or  animal  

 Hair growth  

1. Anagen – time when hair is actively growing from the roots  ∙ Up to 6  

 2. Categen – transition between active and loss stage – slowed  growth

 3. Telogen – final phase resulting in hair loss  

 Metabolic Effects  

∙ Boy who has a zinc deficiency is very thin. They can undergo  treatment for it to grow stronger  

Hair Coloring  

∙ 75% of adult females say they color their hair  

∙ Most popular color is red  

∙ Permanent coloring requires chemicals to reach into the cortex (hair fiber) through the cuticle

o Have to go through the cuticle through harsh chemical  process.  

o There they react with the cuticle, changing the color and  becoming too large to be washed from the hair  

o Chemicals : ammonia, hydrogen peroxide,etc  

∙ Hair color – green – Natural green comes from copper in hair. Can  come from CI in pools or Cu water pipes

 Hair perms

∙ To change the shape of your hair you have to break the sulfur bonds so you shape the hair in the way you want it to and then you  reconnect the bonds  

∙ In this process the bonds mis match like across so it can retain the  shape

o S3 with s2 instead of s3 with s3

 Severely damaged hair – The continuing destructing of the cortex of a hair: the long parallel bundles of keratin have been exposed and can be  seen clearly  

Sometimes hair can be racial identified  

Hair – species identification  

∙ Look at the cuticle to identify the species

o Human, cat, dog, mouse  

How did it fall off

∙ Depending on how it looks you can identify if the hair fell off  naturally or gets ripped off

o Pull blood vessel off when its pulled and exhibits stretching  and damage to the root area  

A Postmortem root band is a band on the hair that comes from dead people

Heat damage – heat burns through the cuticle and changes its shape

Fiber Analysis (non hair)  

∙ Synthetic or natural (plant, mineral, etc.)

Forensic Fiber Analysis Case  

∙ Cereal homicides in ATL

∙ Lots of dead bodies around a river  

∙ Found dog fibers and 2 synthetic fibers (yellow and purple)  associated with carpets  

∙ They did a stakeout and stopped Wayne Williams and searched his  crib and he had the dog fibers and carpet fibers  

∙ The fibers in the carpet were unusual in ATL and they tracked it  down to a specific manufacturer and left Wayne Williams as the only suspect  

 Polymer – bunch of small units of low molecular weight joined  together to make a big one.  

 -Natural Polymers  

∙ Biopolymers

o Proteins – amino acids  

o Carbohydrate – Aldehydes and ketones  

o Nucleic Acids – complzex …DNA

o Spider silk  

 -Synthetic Polymers

∙ Organic polymers synthesized from organic monomers  ∙ Plastic – “capable of being molded”

Spider Silk  

∙ Composed of disordered proteins (like cooked spaghetti) which give  flexibility and ordered units (like rods) to give strength.  

∙ Extremely strong – on a weight basis stronger than steel  

 Plastics: Properties  

∙ Plastics have a large range of properties – from soft and opaque to  very hard and transparent  

o Length of chain  

o 3D arrangement of chains  

o branching of chain

o composition of monomer units  

o bonding BETWEEN chains  

o Orientation of monomer units WITHIN chain  

 Polymers  

 5 monomers that make up most of synthetic polymers  ∙ ethylene – polyethylene

∙ Vinyl Chloride – poly vinyl chloride

∙ Styrene – Poly Styrene  

∙ Propylene  

∙ Ethylene Glycol and Terephthalic Acid

Polyethylene  

∙ High density Polyethylene (HDPE)  

o Straight chain polymer – chains “pack” together tightly like a  crystal – high density, high strength, high mp  

∙ Low Density Polyethylene (LDPE) –  

o Branched chain polymer – side groups impeded “packing” of  chains

 Low density, low strength  

Shroud of Turin Case – Fiber Analysis  

∙ Piece of cloth in a church  

∙ Shroud was used to wrap bodies in so the flies won’t get to it  ∙ There’s an outline of a body in it  

∙ Wanted to see if it was authentic so they had to do radioactive  decay test where they burned a lil piece of the cloth off the edge o They found out the that fibers were woven with old and new  hemmed cloth that was woven when it was getting raggedy  so they didnt have a correct date.  

∙ They think Leonardo used a camera obscura to put the image of  the body  

Paint  

Pigment – has color  

Medium – stuff that holds it in place

Liquid – allows you to slather it on and then it dries

Paint chips

 Pieces of paint that’s left behind  

∙ Automobile finishes – contain an electro coat, primers, color coat  and clear coat  

∙ Determined by microscopy and spectroscopy  

Paint analysis Case  

∙ Axe murder

∙ They knew that bcz whoever did it put the axe down on a pillow and left behind image of axe in blood and paint chips on the axe that  matched up in analysis  

∙ Figured out who owned the axe bcz it was an unusual shape  

 Biometrics – measuring biological stuff that is individualized  ∙ Indicators  

o Universality  

o Uniqueness

o Permanence

o Measurability  

o Ease of Use  

∙ Ex:  

o Writing  

o Vein pattern  

o Fingerprint

o Eyepattern  

Medico-legal Investigations – the crossover between medicine and  the laws  

∙ Assigns responsibility regarding the causation of an injury or ailment o Death investigations

o Abuse and Human Rights Issues  

o Patient rights  

Role of Forensic Pathologist  

4 broad determinations to be made:  

∙ Cause of death – medical diagnosis denoting disease or injury  ∙ Mechanism of Death – altered physiology by which disease/ ∙ Manner of Death  

i. Homicide

ii. Suicide

iii. Accidental

iv. Natural  

v. Undetermined

∙ Time of Death  

Systems

∙ Crowner – Ancient, King’s representative for examining deaths ∙ Coroner – elected official, may have no medical experience o ** require HS diploma that’s it.

o They initiate cases that involve death?  

∙ Medical Examiner – appointed by government,  

o **They protect the public heath ( ask if deaths relate to  problem for the public) **

 Appointed by government, licensed MD or DO

 Death Investigator: usually non-MD but highly trained

∙ Forensic Pathologist -  

 Duties of the medical examiner

∙ Document an interpret injuries and disease  

∙ Collect evidence  

∙ Estimate postmortem interval – the time between the death and the time you find the body  

∙ Determine and certify the cause and manner of death  

∙ Authorize cremation (50%) and organ and ti

∙ Testify in court  

 Deaths examined by Medical Examiner  

∙ If no doctor available to sign death certificate  

∙ Violence

∙ Sudden of unexpected death  

∙ Threat to public health – die of ebola?

∙ Prisoner or in a prison  

∙ Suspicious, unusual, or unnatural  

∙ Related to an occupation  

∙ Related to medical procedure (medical misadventure)  

 Six Critical Questions of a Body – that medical examiners pose ∙ Who are you  

o DNA testing – best

o Dental comparison  

o Fingerprint comparison  

o Physical Traits (unique – scars n tattoos)  

o Visual ID by friends or family – worst (bcz they look different  dead)  

∙ When did you become ill – time frame

o Time of death  

 Ante mortem – prior to death  

 Perimortem – abouth the time of death – depends on  who is defining it  

 Postmortem: Afterdeath  

 Postmortem Interval (PMS): The time between

 Can estimate time of death from:

 Body Temp (algor mortis) – temp drops when  

you die and the rate could be different based on  

∙ Faster in water

∙ Affected by wind and insulations

 Rigor Mortis – Muscles stiffening when dead.

 Livor Mortis (Lividity) – blood settles in the body  

after some time in purple spots  

∙ Gravity causes blood to the lowest part of  

the body – 1-2 hours when you are still able  

to blanch when the spot gets white when  

you apply pressure and then it gets pink  

again when you let go  

∙ Blanching stops – 8-12 hours in  

 Autolysis  

 Putrefaction  

∙ Where did you get hurt – place

o Investigation of the scene and circumstances  

∙ How ?

o Cause of Death & Manner of Death  

o Cause of Death – solely a medical determination – disease  or injury that actually brings about the death of the person   Proximate cause of death – initial injury that leads to sequence of events which cause death  

 Immediate cause of death – injury/disease that  finally kills the person  

 Injuries take precedence over disease for determining  the cause of death  

 Blunt force trauma, sharp force trauma, drowning

o Manner of Death – intent or series of events that brought  about the death : homicide, suicide, accident, natural and  undetermined

 Homicide – when death is caused by someone else ,  regardless of intent  

 Suicide – death brought about intentionally by the  person who dies

 Accidental – violent, unexpected death that was not  

caused by an intentional or criminal act by another  

person  

 Morning traffic, poisoning, fall – top 3

 Natural – Due to disease, illness or pathology

 Undetermined – when a classification can’t be  

reasonably made  

 Autopsy – dissection of the body to find out what happened sis  ∙ When do you do it?  

o When the cause of death is suspicious

o Death arose from violence  

o Death from public health risk  

o Death from low risk medical procedure

o When they were pronounced dead in occurring when 24 hours of being admitted unconscious  

o Any death that is delayed as result of a previous injury  

 if someone injuries someone and they end up in a coma  

and they die – homicide  

∙ What – dissection and examination of body to determine Cuase and Manner of Death  

o Access Organ Systems like – heart, lungs, liver, spleen, brain.. o **leading cause of autopsy is – Assault (homicide)

 Types of Wounds (Trauma)  

i. Lacerations  

ii. Incised Wound

iii. Puncture

iv. Abrasion  

a. Can look at the level of healing that occurred bcz healing stops after death  

v. Contusion  

a. Color changes a bruise goes through can give rough estimate of  time of injury  

i. Dark blue/purple, blue, green, yellow, fades away.  

∙ Assumes person is healthy  

vi. Gunshot  

a. Can determine  

i. Type of firearm

ii. Distance between gun to victim  

iii. Entrance vs exit wounds

iv. Track of projectile  

v. Stippling – powder burns on the skin when the gun is inches to a few feet from the victim  

 Asphyxia and Strangulation  

∙ Asphyxia – dying by lack of oxygen  

o Drowning – results from inhalation of water causing choking   You don’t have to have water in lungs to drown because  

your larynx could seize up  

 Diatoms in someones lungs – water from lake or ocean –

prob drowned

o Smothering

∙ Strangulation

o Homicidal, suicidal, accidental  

o

 Burn and Blunt Force Wounds  

∙ Wounds caused by heat, chemicals, or electricity  

∙ Position – take note on the name of the position idk it

∙

1. Xray  

2. Ultrasound

3. CT

4. MRI – Magnetic Resonance Spectroscopy –  

a. Visualize soft tissue by measure proton magnetic alignments  relative to an external magnetic field.  

Electron Spin  

∙ Electrons have spin properties  

∙ Protons are magnets  

∙ Canoe analogy with the spinning proton

o If proton is against the external magnetic field, then it has  more energy and vice versa.  

o Amount of energy (delta E) depends on what molecule  H is part of  

o If you “zap” with energy and find out how much energy is in it  you can figure out the moledul its attached to (h20, ch3 etc)

 MRI

∙ Advantages  

o Images soft tissues ( only those with hydrogen atoms almost  all of “soft tissue)

o Images function through the use of contrast media

∙ Disadvantages  

o Relatively expensive equipment  

∙ Very strong magnetic field  

∙ What you get – 3D info!  

o They look at slices any way they want  

 Virtopsy  

∙ Virtual Autopsy!

∙ They can see they body all over on the computer so they can  narrow stuff down – doesn’t mean they don’t need to do an autopsy  

 King Tut  

∙ They found King Tut 40 ft under the ground with perfectly kept  artifacts

∙ Did a virtopsy and found that there was a hole in his head  o Found that that was a postmortem hole where they cut his  head to get his brains out  

∙ Cause of Death – located in his knees  

o Kneecap is broken perimortem-> a lot of blunt force trauma

o Other knee just ripped off

o Found out that he survived it initially bcz of healing – scab  formation  

o He has a septic infection that eventually killed him  

o

 Define as the field of study that deals with the analysis of  human skeletal remains resulting from unexplained deaths  

 Answers the following  

∙ Structure and function of the bones of the body  

∙ How old is the bone  

∙ Is the bone human  

∙ If this object bone or not  

∙ Construct biological profile from skeletal remains  

∙ Prepare facial reconstruction from skull  

∙ **bones last the longest  

 Forensic Anthropology – Goal: biological profile  a. general description  

b. Sex of decendant  

c. Age of decendant  

d. Ancestry of decendent  

e. Assessmnet of trauma

i. Ante, peri, post mortem  

∙

f. *** KNOW THE BONES THAT ARE LABELED IN THE SLIDE

Osteology – study of skeletal remains  

∙ Human bone vs Animal bone

o Macroscopic differences  

 Radiology  

 Observation  

 Measurement  

o Microscopic differences  

Bones  

∙ Compact bone  

o Outside with strength  

∙ Spongy bone  

o Inside  

∙ Epiphyseal disks – where bones fuse together in the growing  process  

o To figure out age – you look at how much of the epiphyseal  disks are fused or not  

 Younger – pieces are prob separate  

 Older – fused together into one bone

Cobblers Basement  

∙ Man accused of murder – he had a lot of bpnes in his house  ∙ They found that they were from animals and that’s legal so its fine  

5 critical questions

∙ Is it bone  

∙ Is it human bone  

∙ How old is it  

∙ Whose bone is it  

∙ How did they die  

Is it Human Bones?  

∙ Microscopic differences  

o Cells? Cell size  

∙ Macroscopic differences

o Know anatomy  

∙ Radiography – looking at xrays  

How old is it?  

-historic

Whose bones?  

∙ Sex

∙ Age  

∙ Stature

∙ Trauma and Pathologies  

Whose bones are they? – Sex of decendent  

∙ Use: Skull, Hip bone or femur  

∙ * skull is second best to look at  

∙ Best is pelvis  

o The Public arch is more U shaped than V shaped  o Look at the side and the “notch” is wider for women  ∙ Can do it with the femur but its pretty suddle  

 Whose bones – Age at Death  

∙ Hip bone most useful for adults – smoother = older?  o Bones and teeth  

o Look at how the bones form and shape  

∙ Long Bone Development  

o More cartilage as opposed to bone – younger

o When you grow there’s cartilage that gets replaced with  compact bone  

o Where the cartilage is still there and bones ‘fused’ –  epiphysis

 Over 25 years old tht goes pretty much away

o Sutures on your head  

 Open when your young  

 Fused when older  

o Teeth –  

 Look at the time that the teeth breaks through gums –  eruption

 Which teeth erupted vs not erupted  

 Panormaic dental X-ray can show If there are permanent teeth left back in the gums or whaa

o Pubic symphasis  

 Good to look foe age to see if smooth (older) or na

o Stature Estiamtes

 Long bones are the best thing to look at – femur!

 Stature (cm) =

More info from skeletal remains

∙ Ancestry of decendent  

∙ Facial bones most Important  

o Nasal aperture

o Teeth Interorbital space

o Mandible  

∙ When bones smoothed over, that means it healed i.e they were  living and survived when sm happened to em  

Trauma  

∙ If you hurt yourself you get a bloodclot and it heals with some  spongy bone and new vessels start to grow  

o bone callus forms then the compact bone  

∙ When someone has been strangled  

o Hyoid bone is injured  

 Individual Identification  

∙ When you go get your teeth filled a pathologist can look at that and  your teeth are now unique  

∙ Looking at repeated wear patterns - show u what the person did  often  

∙ Dentures - guy with no teeth assumed to have dentures  ∙ Dental reconstruction – root canals you can see that  ∙ Facial reconstruction  

o You could put a structure on a skull lol

 Case Study – JFK Assasination

∙ Sniper on 6th floor shooting down a president and governer ∙ Harper bone  

o Day after kennedy was shot a kid found bone around the  crime scene as part of the occipital bone of Kennedy.

 Back of ya head  

 That could only happen if there was a second shot so it  would throw it off the head  

 Actually not the occipital bone  

 His occipital bone wasn’t there  

 It has a suture, near point of wound  

 Looked at the curvature

∙ ITS ACTUALLY PARIETAL BONE.  

∙

           Forensic Ecology 

 Relationships between living and non living world. Living  things are Forensic Witnesses.  

 Looking for observable changes that can provide unique legal  information.  

 Habitat – non livin stuff  

 Uses:  

∙ Estimations of post mortem interval - time elapsed between the  discovery of remains and the actual death of the organism  

 Entomology - study of insects

 Zoology – study of Animal life

 Botany – study of plant life

 Proxy indicator – Proxy “stand in”

∙ Small amounts of identifiable material from an ecosystem than can  indicate with relatively high accuracy information about the entire  ecosystem from which they originated  

o Ex: pollen  

 If I see pollen that is unique to your fancy backyard then it came from there

 Forensic Botany - study of plant life  

∙ So many species

∙ Uses

o Tracking a victims movement

o Validating Timeliness of events

 Plnts heal too so If someone was walkin thru the forest  you could know when they passed there.  

o How long someone has been dead.  

 Decomposed body – when person died they fell and  

landed on a flowering plant and when they removed the

body they knew that the flower was flowering during  

time of death  

 That flower on blooms two weeks in the  

summer - > eliminate suspects  

∙ Case  

o Stepfather in a a case claims that they were never around xyz place but they found the pollen that’s around that place.  

o His backyard has no pollen like that

∙ Weapons  

o Trees age and get rings so it can identify age of weapons like  bats, etc  

 Palo Verde Tree

∙ Found a body under a tree

∙ Pager at the scene led to some guy named Mark being a suspect  but he said he was not there

∙ They found the specific tree seed pods in the truct and the DNA  of the pods matched with the crime scene. #caught

 Plant based poisons  

∙ Plant poised put in an Umbrella weapon to kill someone

CHE 113 Exam 1 Study Guide 

This exam covers topics in class from the Chapter 1 –  Chapter 5. There is a large amount of information to know,  so I would focus on what he highlights in class. This study  guide mentions everything he spoke about from the first  lecture to the one covering DNA.  

 Chapter 1 – Forensic Science 

Forensic Science History!!

∙ It began in the late 1700s  

∙ Real application of the scientific method didn’t start until the  1900s

Important People  

∙ Alphonse Bertillon  

o Late 1800s

o ID repeat offenders

o Anthropometry  

∙ Alexandre Lacassagne  

o Criminal Anthropology  

∙ Edmond Locard

o Application of scientific techniques

o First to set up a forensics lab

Locard’s exchange Principle (Edward Locard)  

The most basic concept of Forensic Science:  

∙ A criminal in contact with something, a cross transfer occurs  o EX: dust, fingerprints, chemical residues.  

Principle of Individuality  

∙ While 2 objects appear as the same, those same objects are  never identical. Something sets them apart  

o Ex: identical twins are not really identical  

Example of the Multidisciplinary approach to Forensic Science ∙ Salem Witch Trials – Bettey Parris in the 1690s became ill o Resulted in dancing and yelling continuously  

1690 Medicine  

∙ Doctors weren’t really respected

∙ King Henry VIII merged the lowlife doctors with the barbers to  make the Great Company of Barbers and Surgeons

∙ The barber shop image

o Red – blood

o White – bandages (spirally bloody bandages)

o Blue – tattoo art?  

Internal Illness: human body incorporated for different  “humours”:

∙ Hot (sanguine: blood)  

∙ Cold (choleric: yellow bile)  

∙ Dry (Choleric: yellow bile)  

∙ Wet (melancholy, black cile )  

∙ Illness was caused by an imbalance in the humors  External Injury:  

∙ The answer is amputation!!

∙ Most died of blood loss, shock or infection  

Nothing was working so they assumed that the illness came from the  supernatural word – Salem witch trials (June through September  of 1692)  

∙ 19 men and women convicted of witchcraft were hung on  Gallows hill near Salem Village  

∙ An 80 yr. old man was pressed to death under heavy stones ∙ Hundreds accused of witchcraft  

∙ Dozen put in jail w/o trials  

∙ Late 1692, everything ended  

In the Salem witch trials  

∙ Checked to see if you had moles and such  

∙ If not, connected the dots on your freckles and everyone had  freckles

the forensic investigation started with Art History – Hieronymus Bosch

∙ Telling stories embedded in his paintings

St. Anthony’s Sacred Fire: Ignis Sacer:  

∙ A chemical used to get into your body that makes you feel like you’re extremities is on fire.  

It’s called ergotism  

∙ Gangrenous Ergotism – nausea, pains I the limb bodily  extremities turn black , dry and become mummified, infected  limbs spontaneously break off at the joints  

∙ Hallucinogenic (Convulsive) Ergotism:

o Flu and fever  

o Nervousness, physical mental excitement, insomnia and disorientation  

o Vivid hallucinations  

o The strange happy dancing - Salem  

Made from what could have been fungus – rye grain  

∙ Has the chemical Ergotamine Tartrate

∙ You put in in bread and the chemical was LSD – which made  the town all crazy – forensic toxicology  

∙ Ergot fungus – fixed version that could cure migraines?  

Scientific Evidence  

∙ What is truth  

o That which is true in accordance with fact

o Truth is very subjective

∙ What is justice

o The state or characteristic of being just or fair

∙ In court you try to determine guilt vs. not guilty, not guilty vs. innocent  

o In court you’re guilty if your get proof “beyond a  

reasonable doubt”

To have scientific evidence be admissible in court you look at  ∙ “Trilogy” of court cases

Scientific Method

∙ form and test hypothesis ->

o Observations and Experiments  

o Theory

∙ Patterns and trends

Scientific Evidence in Court  

∙ Why do we want scientific evidence in court  

o Forensic evidence is aimed at informing the court where it lacks expertise

o Assist in determining fact

∙ What is admissible evidence?

o Real Science vs. Pseudo (Quack) Science  

o Established how to determine the difference through 4  primary cases (Frye, Daubert, Joiner, and Kuhmo) –  

KNOW THEY NAMES don’t need to know the date  

Frye Case

∙ Homicide of Dr. Brown during robbery  

∙ Later Frye captured and confessed.  

o There was a lot of evidence against him  

∙ Strong Prosecution Case (1923)  

∙ Defense introduced the polygraph and it seemed like they  couldn’t tell that the guy was lying so the polygraph got threw out the case  

∙ Take Home: They said they would admit evidence if there was  general acceptance through experts in that particular field  o Through: Books, papers, prior judicial decisions, length  of existence of technique  

∙ Problems with Frye:

o Inflexible and slow for new developments or extensions  of existing technique and methods

 Requires complete agreement in the scientific  world so that doesn’t happen very often.  

Daubert Case – Progression  

∙ Drug called Bendectin prescribed for nausea and EVP  ( excessive Vomiting in Pregnancy)  

o People were saying that they caused Limb deformities o They was clinical evidence against that claim  

∙ Daubert  

o Got experts to say that they CAN cause birth defects in  animals if given in large quantities  

o Court determined that the daubert evidence did not  meet the general acceptance  

∙ Alternative standard relative to Frye: Takeaway:  o More flexible:  

 A witness qualified as an expert by knowledge  skill, experience, training or education, may  

testify. If

 It’s based on sufficient fact or data

 It is a product of reliable principles and  

methods

 The principles are applied reliably to the  

facts of the case.  

∙ ACTUAL TAKEAWAY  

o Assigns trial judge the gatekeeper responsibilities in  determining the admissibility and reliability of scientific  evidence

General Electric vs. Joiner Case  

∙    Case where GE was accused of a drug that was cancerous  (PCB)

∙    So conclusions come from data, and if an expert has data and  also has an opinion that’s not related to the data, the jury can disagree with that sentiment  

Kumho Tire Case  

∙    People felt like the tires were defective and therefore caused  injury..

∙    Testimony was essentially unreliable  

 ∙     conclusion  

o “make certain than an expert employs the same leveled of intellectual rigor that characterizes the practice of an  expert in the relevant field”  

            Melendez-Diaz vs. Mass 

 ∙     Lil confused on this one.  

          Functions of the Forensic Scientist  

∙    Examine evidence

∙    Perform the appropriate analysis or measurement  ∙    Render a conclusion based on evidence

∙    Testify in court  

**at home reading in the lectures  

Uncertainty in Measurement  

∙ Precision – how closely individual measurements agree ∙ Accuracy – how closely the measurements agree with the  true value  

 What is Evidence?

∙ Evidence – info that can influence beliefs of an observer  about a specific legal question  

∙ Must be more probative (why) than prejudicial (accusatory)  

Role of Forensic Science

∙ Science is a process that permits one to test hypotheses ∙ Science cant prove anything more complex than a simple fact ∙ Science operates by falsifying hypotheses not proving them.  To Test whether xyz NOT establish xyz

Chapter 2 – Physical Evidence What is physical evidence?  

Any material object that plays some actual role that gives rise to  the litigation, introduced in a trial, intended to prove a fact in issue  based on the object’s demonstrable physical characteristics.  ∙ Ex: blood, semen, silica, documents, drugs, fingerprints  

Physical Evidence: Analysis

∙ Identification - What is it? Determination of physical or  chemical identity of a substance with a near absolute  certainty as existing analytical techniques will permit  o EX: drug analysis, species determination  

o Methods : gas chromatography/ mass spectrometry ∙ Comparison – Very important. Comparing a sample that we  collected and compare it with a standard or exemplar to  determine if they have a common origin.

o Is this fingerprint the same as the one in this crime  scene.  

Comparison: Physical Evidence  

∙ One to many Matching  

o Collected one and then trying to see like everything you have and see if it matches up on the data base

∙ One to One Matching  

o Comparing crime scene fingerprint with the one you  have .

o Ex: the iPhone compares the incoming fingerprint to the fingerprint you put in, not everyone’s fingerprint on  

earth.  

 Physical Evidence: Types

∙ Class (group) Characteristics – Properties of evidence that  can only be associated with a general group and not with a  common source

o Ex: blood type, paint or dye lot  

∙ Individual Characteristics – properties of evidence that can connect a sample and standard to a common source (with  high probability)  

o Ex: fingerprints, unusual wear patterns, tool marks,  bullets, knives, shattered headlight

Advantages of Class Physical Evidence

∙ Multiple types of class of evidence may lead to an extremely  high chance that they originated from the same source.  ∙ To find the probability of a person having x,y and z you  multiply the general probability of x y and z by eachother.  

Physical Evidence – Lindberg Kidnapping Case  

∙ Child (20 month old son) put down for bed was kidnapped.  Ransom note on window sill

∙ Lots of evidence was found…. Mud, footprints

∙ The child was found dead in the woods – blunt force trama  ∙ My son made a whole homemade ladder that they used to  abduct the kid

o There were floor boards missing in the attic  

o The boards age rings matched up . the chance of that  happening was od small

Kennedy Assassination  

∙ The bullet hit the president and the governor so it makes  sense at their entry points for it to be one gun that was shot  that went through both of them  

∙ Locards Exchange Principle – Whenever two objects come  together they must affect each other in some way. Something  is likely to be exchanged between them.  

Principle of Individuality – Even though two objects may be  indistinguishable, they can never be identical  

**4th Amendment defends our privacy and no warrants will be  used unless there is probable cause

∙ we have the right against “unreasonable searches and  seizures”

o What is unreasonable?

Allowances for warrantless searches

∙ Consent

∙ Search of person or property within immediate control of  person in a lawful arrest.  

o The backpack on the guy you arrest  

∙ An emergency

∙ Plain View

∙ Roadside Checkpoints (immigration and DUI)

∙ Airport, boarder searches

∙ The need to prevent the immediate destruction of evidence ∙ Stop and frisk -> suspect criminal activity

∙ Inventory searches. (ships/ cars of suspicious things) ∙ National Security (USA Patriot Act)  

∙ Administrative Services (safety, fire)  

4th Amendment

∙ Only applies to government officials -> NOT private security  officers -> mall cops  

∙ Illegal search can lead to elimination of evidence or  overturning conviction (but may be used in the sentencing  phase

∙ Under most circumstances, a warrant is needed

∙ But, only when there is a “legitimate expectation of privacy”  phone booth vs. public bathroom -> 4th Amendment kicks in  o If you put the camera in a stall you need a warrant but  by the sinks you don’t  

o Phone booth : need the warrant if you put a  

microphone and will hear the audio, but not for a  

camera because everyone can see you in there  

4th Amendment  

∙ supreme court generally does not want to put under  restrictions on the daily work of law enforcement  

∙ Ownership to give consent?  

o Dorm rooms, home bedroom, etc.?

o You can only consent to share spaces.  

o As long as the kid doesn’t pay rent the mother can  agree to searching  

∙ Mistaken Search, “Good Faith”

o Mistaken got other people w/drugs when looking for the  guy w/gun -> admissible evidence

∙ Searches in malls, stores, Disney World, backpacks, schools -> don’t follow this?  

∙ Car GPS data, black box or police affixed gps  

o Need a warrant unless the cars on fire  

o If they want to track a car -> need a warrant

∙ Pat down frisks-> find drugs can be legal if they see  something  

∙ Good Faith  

Plain View Doctrine – don’t need a warrant to seize things that  are in plain view. From a place the officer has a right to be (sidewalk,  roadside..)

Exclusionary Rule – If you got evidence illegally -> It’s inadmissible

Fruit of the Poisonous Tree Doctrine – If you get evidence illegally,  anything else that comes from that is also illegal

Illegal evidence can be used:

∙ When sentencing  

∙ Admissible in civil cases and deportation cases  

∙ To impeach/discredit a witness  

Collection of Evidence – Legal Precedent –Miney vs. Arizona ∙ Drug bust went wrong when undercover police got killed  ∙ Police spent 4 days searching and seizing  

∙ Mincey was arrested and convicted

∙ Inadmissible evidence because they spent 4 days, the  “emergency” lasted a shorter time  

Michigan vs. Tyler  

∙ Building destroyed by fire was put out early in AM ∙ Building left unsecured and they in on days (4, 7, and 25) to  get evidence

∙ Inadmissible evidence – uncontrolled scene, they waited too  long and they cant say what or what not had been tempered  with.  

Physical Evidence  

∙ Must be recognized at crime scenes

o What relates to the crime and what doesn’t  

∙ Must be properly collected, preserved and controlled ∙ Only aids in investigation

Steps take at a Crime Scene  

∙ Secure and Isolate the scene  

∙ Render medical help and arrest suspects (if need)  ∙ Preserve and protect evidence (isolate area)

o Exclude unauthorized personnel  

o Designate Officer in Charge (with authority)

o Establish boundaries

o Document site

∙ Collection of Evidence

Crime Scene Searches – Lockerbie Bombing  

∙ 35 SU students killed by terrorist bomb in Dec 15. (Pan Am  Flight 103)  

∙ Crime scene spread over 845 sq. miles of Scotland ∙ Discovery: Crime Scene spread over 845 sq. miles of Scotland  and came out with a little piece of evidence that helped them  solve the case

Chain of Custody : documentation of transfer of evidence ∙ It's a piece of paper that everyone has to write on if you’ve  touched the evidence.

Chapter 3 –Science vs.  

Pseudoscience 

Pseudoscience – saying dihydrogen monoxide kills!!-> it’s H20  Science – systematic knowledge gained through observational  experimentation

Pseudoscience – a discipline or approach that pretends to be  science

∙ Damages reputation of scientific work  

Audi 500 Case  

∙ Claims that drivers reported acceleration even when the  brakes were applied  

∙ “60 minutes” story on claims led to increased claims with  many lawsuits  

∙ Demo: full acceleration with foot on the brake prevented car  from moving  

o Court finding: for plaintiffs (against Audi)  

 Science vs. Pseudoscience  

∙ Pseudoscience relies on trust while science relies on  experimental validation and evidence.

o Exaggerated claims  

o Try to fill voids of scientific understanding and when  they fail they make science look bad  

o Based on hearsay  

 Testing ideas: Statistics  

 Statistics: given the little information what can I say about the  population  

 Probability: given the population, what can you say about the  individual

∙ Mean, median, mode

∙ Standard deviation :indicates the breadth and the  distribution of data in a set  

o If small, then steep hill if large, then spread out curve ∙ Error bars: a convenient way to show directly on the plot  

Probability  

Of this and this happening = this times this

 Chapter 4- Microscopy 

 We use microscopy to extend our human senses: sight, smell,  touch….

 How our Eyes work

∙ Pupil, lens (that acts as a magnifier)

∙ In the back they’re specialized cells (retina) causes those cells to send electrical impulses from the light  

∙ We have to replace the light with something smaller so we  magnify the image.  

 Compound Light Microscope

∙ Most common: compound light microscope

o Has two lenses that the light can pass through

 Dark field Microscopy

∙ Shows a light silhouette of an organism against a dark  background.  

∙ The light reaches the angle because the light bends so the  image is very bright  

∙ Pretty cool

∙ Block the normal straight line light, and only light that  aluminates the sample reaches my eye.  

Comparison Microscope

∙ 2 microscope that you use to bring an image together – there  are two lenses, one for each eye  

∙ split image comparison of banknotes: on the left original, on  the right -> forgery  

Phase-Contrast Microscope

∙ this microscope splits a beam of light into 2 types of light, and brings them together to form an image of the specimen ∙ “in phase” – image is brighter

∙ “Out of phase” – image is darker  

Polarizing Microscope

∙ Light confined to single plate that is polarized

∙ Reduces glare by transmitting light in a vertical plane only.  o you have to twist the sample to be able to get the like  through so that you can see  

 Optical Isomerism

 Fluorescence Microscope

∙ Specimens are stained with fluorescent chemical so it glows  under the UV light  

∙ Appear as dark background and its glows

Stereomicroscope

∙ Also called the dissecting microscope

∙ The light goes to the sample and bouncing everywhere till it  gets to your eye  

Electron Microscope

∙ A beam of electrons are shot through the specimen  ∙

Staining samples

Chemicals that are added that stick to certain structures that allow me  to see them easier.

Chapter 5 - DNA

Forensic DNA: Two Tales  

Had the attackers DNA patterns from each case and went to go  compare them to 500 samples but they didn’t even match  ∙ Colin Pitchfork Case (1986)

o He confessed to his friends, they turned him in and they compared his DNA to the sample they had from the  

scene.  

 First time dna was used for conviction  

∙ WTC Case (2001)  

How DNA Works: Nucleic Acids

Nucleic Acids – chemical carriers of generic information (DNA and RNA)

∙ Consist of;

o A phosphoric Acid Molecule (phosphate)

o 5 carbon sugar (ribose)

o Nitrogen base

 Adenine, Guanine,…

 Information lies here

∙ All linked through condensation reactions to form polymers  ∙ Double Helix with Two strands via hydrogen bonds when  the bases line up  

o G to C  

o A to T

DNA in the Cell

 DNA strands coils up to form chromosomes ∙ you get DNA from your mom and dad  

Human Genome Project  

∙ determined out we have 30,000 genes that code for  things we need

∙ found humans share 93% of our DNA with worms  ∙ only 1.5% of DNA is codes for compounds -they rest is  complicated  

 gene – short portion of DNA that codes for something  ∙ happens on the coding sections

transcription  

∙ 3 base pairs corresponds to 1 amino acid

∙ Builds Proteins  

∙ Proteins – enzymes, all functions for life.  

∙ The dna strand splits in half and coding strand gets  transcribed (matched up)  

o Translation: Then it goes to the ribosome where  every 3 bases get amino acids that make proteins

 DNA Cellular Sources  

 Nuclear DNA  

∙ Located in nucleus

∙ Half mom and half dad

Mitochondrial DNA  

∙ Located in mitochondria  

∙ Inherited just from mother  

Where is DNA  

Cellular Matter – where is DNA everywhere?

∙ (slide)

Human Identity Testing  

∙ Forensic cases – match or eliminate suspect with evidence  ∙ Paternity testing – Match or eliminate possible father(s)

 African Lemba Lineage

∙ Looking at a marker on the Y chromosome that men have  ∙ Found

o 50% of marker founds in Cohanum males were in 10%  of all Jews  

o they have some kind of relation  

 DNA Analysis

∙ Collection of Sample

∙ Separation and Purification of DNA

∙ (slide)  

 DNA Fingerprinting “RFLP”

∙ “Restriction fragmentation –“

o Restriction DNA with cut DNA into fragments in different lengths  

∙ Some enzymes recognize a set of bases and when they do,  they cut the hydrogen bond

o Now you have comparable fragments for DNA  

suspecting

∙ Gel Electro.

o Put the fragments in machines and then they line up  based on size  

o So its easier comparison  

Tandem Repeats  

∙ Sequences of DNA that repeat over and over next to  eachother  

o Intergene region that contain many A,T,C,G repeats  ∙ Forensic DNA typing uses tandem repeats

o All humans have many tandem repeats  

o Great variation per person – how many and where is  different  

 Somebody could have 4 tandem repeats or 6  

tandem repeats for one gene

PCR/STR DNA Typing  

∙ Uses shorter, more stable DNA lengths and deals with less of  the simple

∙ Works with the tandem repeats  

∙ Allows you to copy the repeated section and they if you figure  out how long the sequence can be