FIS 202 Final
Event Mechanism categories
- static blood dispersed from a point source - blood dispersed in a jet - blood dispersed as a function of accelerated motion - blood accumulates or flows on a surface - blood dispersed as a function of secondary contact with a surface - blood dispersed as a function of gravity
Body Fluid Tests
-sperm/semen = acid phosphatase - saliva = amylase + starches
Strip Search
1 or 2 people exterior scenes w large area divide space into strips and move down the strips, turning after each strip to go to next strip
3 Specific Scene Integrity Issues
1) ADDITION of material to the scene (POST-INCIDENT ARTIFACTS) 2) DESTRUCTION of material in the scene 3) MOVEMENT of material in the scene ( if unchecked/ unrecognized)
Landfill recovery methodology
1) ID appropriate cell/ cells in consultation with the landfill operator 2) landfill operator removes cells that were deposited on top of cells in question 3) once cell exposed, use backhoe/ bulldozer throughout operation - observation and rake teams
Evaluation of Firearm Steps
1) Operational Check 2) Note any abnormalities about firearm 3) Look for class characteristics between gun and ammunition
3 Basic Glass Determinations
1) Type of Glass 2) Direction of force (can help stage the scene) 3) sequence of force (can help stage the scene)
Fire Scene methodology
1) assessment and observation and documentation 2) examination
Methodology of bloodstain pattern analysis
1) become familiar with entire scene 2) ID discrete patterns among various bloodstained surfaces 3) classify patterns based on their physical characteristics using same form of established taxonomy 4) evaluate aspects of directionality and motion in stain pattern 5) evaluate angles of impact, points of convergence, areas of origin, if necessary 6) evaluate interrelationships among stains, patterns, and other evidence 7) evaluate visible source events to explain pattern ( based on all above) 8) validate the analysis through some form of peer review
Reconstructing entire events steps
1) collect data, establish likely events 2) establish event segments from the data available 3) define associated event segments 4) order and sequence the associated event segments 5) audit the information 6) determine and final order the events 7) final flowchart of the overall incident based on the event and event segment sequence
Basic Methodology for Crime Scene Photography
1) document entire scene as soon as possible using overall photos 2) photograph all fragile items of evidence as soon as possible using evidence establishing and evidence close up phots 3) place photo placards in scene on all items of interest and reshoot a second series of overall photos 4) document all known evidence with evidence establishing shots and close up shots and use placards when possible to clearly differentiate from one another 5) if items discovered in later stages - ensure appropriate photos are created and may need to take additional photos even though scene has been altered 6) use road mapping technique to create photos that clearly demonstrate result of examinations such as bloodstain pattern analysis or trajectory analysis 7) always use film roll reference card and a photo log
Evaluation of Bullet Steps
1) list possible weapons based on: - number - size - caliber - twist of lands/ grooves of bullet 2) fire additional bullet from questioned weapon + look at striations - allows for exclusion/ individualization
3 Underlying principles of bloodstain pattern analysis
1) pattern diversity principle -variations in combinations of blood volumes and forces acting on those volumes lead to recognizable classes of patterns 2) principle of stain shape and vector correlation -the shape of certain bloodstains provides indicators as to the direction of deposition as well as to the spatial origin of the blood 3) physically altered bloodstain principle - once exposed, blood will react to environmental conditions in a predictable manner
h rhodes
1933 clues and crimes goal was to decide how crime was committed and order of events
Luke May
1933 scientific murder investigation
tom bevel
1997 bloodstain pattern analysis: with an introduction to crime scene reconstruction refined- practical crime scene analysis and reconstruction 2009
Overall Photographs
1st photographs taken depict general condition and layout of the scene how is scene oriented, where major visible landmarks are, condition of scene prior to significant alteration
Rectangular coordinates
2 measurements best if clear and specific boundaries (interior walls) fix evidence by measuring at right angles form evidence to surrounding walls/ surfaces
Defining team composition
2 ways: -area approach - function approach approach chosen based on scope and nature of scene
Sketch and Measurement team
3 people can have 4
Triangulation
4 measurements for items of regular shape 2 measurements for items of irregular shape effective for fixing evidence
6 Steps at a Crime Scene
Assess Observe Document Search Collect Analyze
Internal Ballistics
Examiner condition and function of weapon -evaluation of ejection patterns -evaluation of gunshot residue patterns/ shotgun patterns -examination of bullets and bullet fragments for trace evidence/ damage
Transitory Effects
FAIL TO STAND OUT until directly observed at crime scene - presence of ice in glass - smell of specific perfume when first arrive
Latent Fingerprints
GENERALLY INVISIBLE created by deposit of normal body secretions
Plastic Fingerprints
IMPRESSIONS where a print has been deposited on a soft surface
Locard's Principle of Exchange
NO PERFECT CRIME "every contact leaves a trace"
Justice
NOT SAME AS TRUTH process by which "each receives his due"
Terminal Ballistics
Pathologist effect of projectiles on body assist in limiting the position of victim at the time of wounding -range of wound -stippling/ tattooing
5 Ways Evidence Can Be Manifested
Predictable effects Unpredictable effects Transitory effects Relational details Functional details
4R rule
Ridge lines on Radial fractures are at Right angles to the Rear (side opposite of the right angles = side force was applied on)
Road mapping
VERY INTRUSIVE 1) recognition of discrete patterns/ defects 2) placement of appropriate labels and scales 3) creation of overall photos of an area with labels in place 4) creation of overall photos of a pattern with labels in place 5) creation of additional evidence establishing photos of individualizing stains/ details when needed 6) creation of close up photos of individualizing stains, defects, or details with labels in place
Patent Fingerprints
VISIBLE TO NAKED EYE created by deposit of contaminants
4 Questions Investigators Ask At Scene For Evidence
What is it? What function did it serve? What relationship does it have to any other items/ evidence or to the scene itself? What does it tell us about timing and sequencing aspects?
impact pattern
a radiating pattern of small circular/ elliptical shaped stains created when blood is broken up at a source by a force
Center-Fire Cartridges
a small primer cap is sealed at center and case of casing lights gunpowder when striked
Porous
absorb moisture Dry: -paper: 1)DFO 2)ninhydrin 3)silver nitrate -untreated wood: 1)ninhydrin 2)powder/brush Wet: -dry then physical developer
Crime Repression
after investigate and ID those responsible
Individual Characteristics
allow to compare item with a specific item/ person -UNIQUE characteristics from natural variation, damage, or wear -will include/ exclude a suspect -INDIVIDUALIZATION
Bloody prints
amido black leucocrystal violet alcohol based fluroescin
Cartridge
ammunition single and complete unfired unit made up of projectile (bullet) (shot pellets or slug - shotgun)
gush/splash
an irregular pattern created when blood is ejected in volume
flashover
any ignitable surface in room will being burning if temp in confined space reaches 1100F
pattern transfer
any stain/ pattern created by transfer of blood from one object to another in which a recognizable characteristic/ image is present in the pattern
smear
any stain/ pattern created by transfer of blood from one object to another through some form of contact 2 categories: -wipe -swipe
In Situ
as found
Crime Prevention
before stop from happening in the first place
intermediate range
between 5-40 inches away from muzzle presence of stippling around wound
Impression Evidence
bite marks tool marks and plastic prints tire and shoe wear
saturation stains
blood drawn into clothing/ other permeable surface may destroy other bloodstains/ patterns of interest
secondary contact stains
blood is transported from one object to another smears wipes swipes pattern transfers
Spatter Stain
blood mass is broken up into small droplets and put into free flight by something circular/ elliptical
Zone search
break area up into distinct areas, each person searches a specific area 2 variations: -for small, confined spaces -for large scene
Penetrating
bullet enters no exit
3 Dimensional sketch
can present crime scene info in a more realistic perspective hand drawn sketches to computer sketches/views
v pattern
caused by flame rising on a wall can show where fire originated down below very standard pattern
Cross-Contamination
caused by inappropriate handling of evidence
Unpredictable Effects
changes that occur AT UNEXPECTED/ RANDOM TIMES to alter scene/ evidence - ems opening doors/ moving furniture and not reporting doing so
Predictable Effects
changes to scene/ evidence that OCCUR REGULARLY - bugs found on dead body at different time periods
Evidence close up / forensic quality photographs
close up with an appropriate scale present next to evidence must fill frame with item of interest
Truth
collection of facts to draw a conclusion
Cross projection/ exploded sketch
combines standard birds eye view with laying down walls to depict evidence that is present on these vertical surfaces
Regulate Noncriminal Conduct
control general behavior patterns prevent chaos
Relational Details
created through investigators ABILITY TO PHYSICALLY PLACE ITEMS at scene - presence of void pattern on wall surrounded by spatter -shell casings in grass
External ballistics
crime scene team trajectory of bullet after leaving the barrel of the weapon -describe bullet defect as penetrating, perforating, ricochet/ deflection, or tangential
james w osterberg
criminal investigation: a method of reconstructing the past
blunt force truama
crushing/ tearing of tissue
sharp force trauma
cutting of tissue
Polystyrene/styrofoam
cyanoacrylate fuming small particle reagent
Elevation sketch
depicts side view of some portion of a scene (typically an interior wall or similar vertical surface)
Close contact/ Hard contact
direct contact/ muzzle pressed to skin
Actions of the Initial Responding Officer
documenting initial information emergency care secure and control the crime scene establish initial parameters -primary focal points -natural entry/exit points -secondary scenes release the scene to appropriate authorities (CSI)
blood into blood
drip pattern pattern of spatter deposited into one another or into another liquid resulting in an accumulation with secondary spatter randomly oriented around the margin
Human Skin
dry dead on scene exam: -adding machine paper -cyanoacrylate fuming -magnetic powder -iodine fuming dry alive on scene exam: -adding machine paper wet: -adding machine paper
Non porous smooth
dry: -cyanoacrylate fuming -powders -small particle reagent wet: -dry and follow with a dry approach
Nonporous Rough
dry: -cyanoacrylate fuming -powders wet: -dry and follow with powder/brush
Adhesive surfaces
dry: -submit to lab if possible -crystal violet, alcohol/ water technique -sticky-side powders wet: -dry and use any of the above
perforating
enters and exits
Phenotalein
ethanol phenothailen hydrogen peroxide PINK
Direction of Force
evaluate radial fractures present in first concentric ring of fractures to determine where/ what side force was applied to -4R Rule
Evaluation of Recovered Casings
examine for number of different marks: - breech bolt marks - firing pin marks - ejector / extractor marks - microscopic variations
Polar Coordinates
exterior scene where evidence is significantly scattered over relatively open area not if line of sight is limited 2-3 basic measurements: -horizontal angle -horizontal distance (between datum and evidence) - difference in elevation (if applicable)
loose skin
extremely close by small gap between muzzle and skin during firing
overhaul
firefighters search for hotspots that might flare up and eliminate if they find one very destructive process
decomposition
first see blue green discoloration in lower right abdomen then swelling of tissue, protrusion of eyes and tongue, blackish blue discolor of tissue
Nitrite compound test
for surfaces close to muzzle at time of fire turns orange validate position of muzzle at time of fire
Crime scene sketch
free hand drawing
charles o hara
fundamentals of criminal investigation scientific method
flowcharting
graphically representing the order of the event segments
terminus post quem
happened after another event
terminus peri quem
happened at same time as another event
Terminus ante quem
happened before another event
5 Basic Elements of Sketch
heading diagram area legend title block scale and direction notations
Manner of Death
homicide suicide accident natural causes undetermined
Mechanical Fit
individualizing form of evidence pieces fit together = must be from same place
Adapted USACIDC Model of Processing Crime Scene
initial notification coordination, assessment, and team call out conduct initial observations deal with deceased photograph the scene document overall observations sketch the scene conduct a 1st recheck of scene release the body collect items of evidence conduct a 2nd recheck of scene conduct a 3rd recheck of scene check beyond the scene conduct an on scene debriefing of investigative team release/ secure the scene process and package evidence conduct a formal debriefing
gunshot trauma
injury produced by a projectile from a firearm
Circle/ Spiral Search
interior scenes begin on outside of area and move in slow spiral inward to middle can also be used in reverse - work your way out of middle
Crime scene report suggested format
introduction characteristics of scene conditions of scene environmental conditions factors pertinent to entry/ exit scene documentation collection of physical evidence search for latent prints additional examinations
Asphyxia
lack of oxygen - strangulation ( garroting and hanging deaths) - smothering - choking -drowning (cerebral anoxia) -positional/ mechanical asphyxia -chemical asphyxia
Line search
large group of people exterior scenes variation of strip search each person walks straight down one strip
Rifle
long barrel designed to be fired from the shoulder RIFLING- series of grooves manufactured in barrel that give the projectile spin
Shotgun
long barrel designed to be fired from the shoulder SMOOTH BORES - no rifling "pump" shotgun - slide action
Trajectory Analysis
look at the impacts of immediate targets, shape of final defect, trace evidence on bullets and information derived from autopsy
Auditing
looking beyond obvious and try to validate/refute previous conclusions
algor mortis
loss of body heat from corpse
events
macro components of an incident
event segments
micro components of an event specific actions at a given point in time
Evidence establishing photographs
mid range photographs frame items not recognizable in general photos in conjunction with some obvious landmark evident in the overall photographs
Crime scene search team
min of 2 people
Evidence collection team
min of 2 people
Photography team
min of 2 people
grazing
minor abrasion passes adjacent to body
chisum and rynearson
most defined methodology before 1997 "evidence and crime scene reconstruction" storyboard approach contained subjectivity - bad
Shot Sequence Determinations
multiple bullets near each other - look at termination points and radial fractures to see order that they were shot in
indeterminate range
no conclusion no markings except bullet defect "distant"
near contact
no more than 5 inches away from muzzle
Trace Evidence
normally CLASS CHARACTERISTICS ( but may individualize in some cases) -hairs, fibers, glass, paints, soil
voids
not true patterns lack of pattern where there should be an otherwise continuous pattern something was in the way
blood pools/ blood flows
obey gravity help establish movement and position of individuals bleeding in the scene
Metal splash
occurs from friction of bullet with a surface use DTO/ rhodizonate to show directionality
Incident
overall situation being investigated
drip trail
pattern of individual spatter deposited on a surface demonstrating movement of the dripping item from one point to another
Non spatter stains
patterns where primary stains are not circular or elliptical
Provision of Services
police have wide range of issues they will help others with
Protection of Personal Liberty
police monitor themselves to make sure not getting in way of others' freedoms
Rim-Fire Cartridges
primer compound is manufactured into rim of casing lights gunpowder when striked
Wet-Bench Serology
provided a description of the questioned blood sample, compared w any known blood sample and offered statistics of frequency of the expected markers CLASS CHARACTERISTIC- not individualizing
point to point search
rarely used in USA designate focal points and move from one focal point to the next
luminol
reacts with heme turns luminescent blue-green
amido black
reacts with proteins turns blue-black in color
peter lamb
reconstructive process has 4 parts: -information - observation - interpretation - conclusions
fly spots
result of fly activity at the scene movement of flies can track blood from body/ bloodied surface and deposit it on surrounding walls/ surfaces
wake effect
ripples in metal shows direction bullet traveled on metal
dr. paul kirk
sam shepard case 1953 "crime scene reconstruction"
Relative chronology
sequencing of event segments this happened before this but after this
edward oscar henrich
set out specific methodology "nothing just happens"
Livor mortis
settling of blood in body due to gravity after circulation ends starts 30 min after death fixed within 8 hrs of death
Handgun Weapon
short barrel designed to be fired with 1 or 2 hands revolver: -cylinder + cylinder gap -manually insert ammunition -distinct GSR pattern when fired Pistol: -magazine -put ammunition in magazine and put magazine into base of weapon
GSRs- Gunshot Residues
significant level of burned and unburned residue discharged along with bullet when fired contain trace amounts of 3 elements: - antimony - barium - lead use SEM + nitrate tests to see
Baseline coordinates
similar to rectangular coordinates best for exterior scene with no evidence landmarks DATUM POINT - start of baseline from where baseline will extend measure distance from each item to a right angle to the baseline
Area Approach
single team handles all areas associated with processing small police departments
tangential
skims surface several shallow wounds
wipe
smear through preexisting stain/ pattern
swipe
smear where blood is deposited onto a surface where it previously wasn't
drips
spatter resulting from blood dripping from an individual/ otherwise bloodied object
Classifying bloodstain patterns
spatter stains: - linear: spurt, cast off, drip trail - non linear: impact spatter, drip non spatter stains: - irregular margins: blood into blood, gush, smear ( wipe or swipe) - regular margins: pattern transfer, flow, pool, saturation
Cause of Death
specific act that lead to death
spurt
stains created when blood is ejected in stream under pressure/ with velocity artery/ heart is breached
cast off
stains created when blood is flung from one object that is either in motion or suddenly stops moving
rigor mortis
stiffening of muscles of body start within 2 hr of death greatest at 8-12 hr after death breaks down 12-48 hr after death
3 Categories of Toolmarks
striation compression saw and drill
On scene fingerprinting
superglue fuming basic powder techniques small particle reagent
Underlying principles of crime scene reconstruction
superposition : layers deposited in timely order continuity: similar things are in same time period chronology: nothing just happens, has a before and after relationship: everything leaves a trace and has a relationship to other objects
Function Approach
team leader tells different teams to do different activities large police departments
Functional Details
the OPERATING CONDITION of items at the scene - could the gun present fire correctly? - was alarm set on clock for a specific time?
Absolute chronology
timing aspects at what time did something happen
Crime scene mapping
to scale drawing
Class Characteristics
traits of evidence that allow the items to be compared/ linked to a group -help to eliminate possibilities
Grid search
variation of strip search do strip search one way and then do the whole process again with strips perpendicular to the previous strips
Compression Toolmark
when a tool is forced into a soft material
Striation Toolmark
when cutting edge of a tool is brought in contact with and slides against a target surface
Zones of possibility
zone 1: most probable -along trajectory and lower than shoulders zone 2: possible but awkward -along trajectory and higher than shoulders zone 3: impossible given the data -physically unable to align barrel and produced the trajectory do to some reason