SABT 6 H LAB SERVICES & DNA Flashcards
2 ID types of evidence that can be collected from arson and explosive evidence scenes.
1 Collection of solid scene samples 2 collection of soil sample 3 liquid samples 4 preservation of liquid containers 5 evidence from suspects and victims 6 incendiary mixtures and devices 7 molotov cocktails 8 chemical incendiaries 9 petroleum products in our environment and the need for control samples
1 List & describe the examination an analyses of forensic that can be performed by the ATF Forensic Laboratory Services.
- Fire Debris
- explosives
- Latent Prints
- FA/ tool marks
- DNA forensic biology
- Question documents
- alcohols
- tobacco
- trace evidence
3 Explain methods of collecting, packaging and shipping arson, explosive and bio-hazardous evidence.
- Fire debris and explosive should be package in suitable air tight containers
- Most other evidence should be placed in containers that breath (boxes , papers, bags)
- Dry any wet evidence when possible to eliminate bacteria growth
- LP evidence secured to items are not moving
- FA render safe, sent magazine, package ammo separately
- Tool marks protect working surfaces and package tools separately from tool marks.
- package items separately unless separating them may cause loss ie (hair or fibers)
- All evidence should be sealed with evidence tape prior to submitting it to the laboratory. Items must be packaged and sealed in a manner which eliminates loss or degradation of the evidence an prevents tampering.
- Place ur initials an the date over the tape
- Put a label on each exhibit identifying the number, what it is, location it was recovered
- Place biohazards labels on anything that may have blood/body fluids on it
Best sample collected on a fire scene are
A. Heavily charred debris
B. Nonporous surfaces
C. Protected from Hear of Fire
C. carpet and especially carpet padding, soil, unsealed wood, protected area under furniture behind baseboards
-Worst sample are
Nonporous surfaces, heavily charred debris, samples with contribution from pyrolysis
T/F Dogs are a tool which allow you to select the best sample.
True BC dog alerts, does not mean that it was set on fire.
What are the recommended container for collection of debris
A. Paper bag
B. Unused clean metal Can or clean unused glass jars
C. ziplock bag
B metal can tight so the vapors can be collected no more than 2/3 full
Glass jars can be used for collection of liquid and solid accelerant evidence
Ignitable liquid are _____ and not _____. Due to marketing practices, the same product may be marketed under a variety of end uses or brand names.
A. Identified/ classified
B Positive ID/ Collected
C. Classified/ Identified
C. Classified/ Identified
T/F Fire debris has to be put in a air tight container
True,
if not airtight can not analyze
Soil sample degradation within how many hours.
A. 12
B. 40
C. 24
C. and refrigerate samples quickly, always collect comparison sample.
ATF Labs do not analyze
A. Drugs and Toxicology
B Fire debris
C. Trace evidence
A
T/F Different petroleum companies put markers in gasoline to identify it as their own.
True
T/F Liquid to Liquid gasoline comparison can be performed at ATF lab
False, can be done but outside of ATF lab
Ignitable liquids are classified as
A. Gasolines, light medium and heavy distillate
B. solvents
C. E-10 gasoline
A.
Chemist Duties consist of identifying ____ and ____ of the explosive device.
A. cause, makeup
B. fuzing, firing train
C. specific ID, classification
B. Fuzing, and firing train
-also the source information for device components parts, Id explosive main charge,
T/F Jobs of the explosive chemist include comparing items recovered from suspects to evidence from the explosive scene and can also evaluate explosive devices to establish devices signatures.
True
Where must the investigator submit incidents of explosives.
A. Crime stoppers.
B. NCIS
C N-Force
N-Force
T/F Latent prints can be found on what type of surfaces
Porous and non porous
True
Porous items should be packaged in
A. Plastic bags only
B Tin can, glass jar
C. Envelopes, paper, plastic, etc
C .
T/F Non porous evidence should be secured to reduce movement during shipping, avoid paper bags if possible.
True
What is the name of the database where suspects LP can be ran
A. IAFIS
B. CODIS
C. Crime Stoppers
A.
The listed items are from what ____ dept at the ATF Laboratory
- ID of FA and ammunition
- function testing
- IBIS entry
- ID of tool and tool-marks
- fracture matching related to FA and tools
- restoration of obliterated marking/ serial numbers
- provide technical on scene assistance ( include trajectory analysis and crime scene reconstruction)
- distance determination based on GSR
Firearms and Tool marks
T/F Firearms examiners can test fire guns to to compare cartridges form CS to the Cartridge case that were loaded in the firearm.
True
T/F Firearm examiners can
1 ID if fired bullet was loaded into a certain cartridge case
2 ID if a cartridge came from a particular box or manufacturing lot
3 Perform lead analysis on bullets
4 Determine the order in which the evidence was fired
5 Specify location of bullets
6 Nexus determination
False
Exams that are completed by ____ in West Virginia
1 Title II determination
2 classification of silencers A. ETB
3 armor piercing classification B. ATF Firearm examiners
4 Antique determination C. FTB
C Firearm Technology Branch
T/F Can agents sent live ammo through the US mail
False sent thru Federal Express
Can agents packaged fired Cartridge casing together in one bag?
-Should you mark on the ammunition components?
No, package individually
-no
What is the name of this
- The program that uses technology in a cohesive network to provide LEO leads
- Network of cold case search engines, works toward finding possible matching fire bullets and casing in databases
- This technology incorporates a database of a firearms ammunition components images
- One of the most important features of this technology if the ability to AUTOMATICALLY SEARCH LOCAL REGIONAL DATABASE. Upon special request, it is possible to initiate a search of any other database in the nation
NIBIN/IBIS National Integrated Ballistic Information Network
This is called
A. Search for trace evidence
B. Determine if a tool was used
C. Determine class characteristics
D. determine type, size and design of tool used to create tool-mark
E. type of action the tool employed
F. individual characteristics -Marks the value of comparison purposes
G. If a suspect tool is received we can
1. determine if suspect tool is of the same class of tool which made the tool mark
2. Perform a microscope comparison of toolmark with using a test mark made by suspect tool.
3. Inter-comparisons of tool-marks from different cases and or scenes.
Tool Mark Examination and comparisons
T/F Can Toolmark examiners ID a particular grinding wheel, file, or saw blade back to a toolmark
false they cannot
Examinations of 1 where the shooter and or target was positioned 2 was the shooter and or target moving 3 number of shooters 4 order of shots possibly
Trajectory analysis External Technical Assistance
1 Analytic Test A shootings trajectory analysis B. Ejection pattern testing 2 Scenario of events to include A shooting position B Target position C. Movements of the shooter and target
Shooting reconstruction External Technical Laboratory Assistance
Distance Determination
Items needed for testing
1 the suspect firearm preferably with magazine
2 The ammunition used in crime, preferably the ammo that was recovered from the scene
3 Target information (eg clothing, house siding, door)
4 information about the environmental condition and possible intervening objects at the scene
1 intervening objects will affect the deposition of gunshot residues
2 some materials may inhibit to the deposition of gunshot residues ie. leather
3 Unavailability of the same or similar ammunition
4 Type of firearm unavailable
5 Environmental conditions
6 EMS and or medial examiners
7 improper packaging and handling
Factors affecting distance testing
T/F Distance determination without the firearm ammunition combination
- Distance determination with reloaded ammunition
- Determination of distance from autopsy photographs or victims
- GSR Identification by instrumental methods i.e on hands or clothing
False
T/F GSR evidence should be bagged in plastic bag
False (airdry, wrap each item separately in paper or place in paper bag, labeled biohazard)
What is
1 body fluid identification ( blood, semen, saliva)
2 DNA analysis
Forensic biology
Chemical substance found in our bodies that is responsible for determining all aspects of our physical makeup blueprint of life
-half from mother and half from the father
DNA found in cells of our bodies
(blood, saliva, vaginal fluid, semen, hair root, (with tissue), tooth pulp, bone marrow
T/F DNA differ from cell to cell in the same person
False,
Does DNA differ from person to person?
Yes, except for Identical twins
-the majority of all DNA are the same BC we are all human.
What part of the DNA is the small portion of DNA that is different, this determines the individual features and is of forensic intrest
Junk DNA
2 cooperies in each cell inherited from both parents uniques to individual
Nuclear
forcibly removed root of hair is suitable for ___ or ____ DNA testing
-Nuclear
Mitochondrial DNA
Suitable for mitochondrial DNA testing only
Naturally shed root
What four type of gun cases are accepted to laboratory
- stolen guns
2 illegal guns
3 Guns used in violent crimes
4 Gun trafficking
T/F Felon in possession cases can be analyzed for DNA at this time
F ( this is due to limited number of DNA analysts, to many felons in possession cases)
- Cannot tell when the DNA sample was deposited on the evidence
- In a complex/ degraded mixture sample, many individual could be included as contributors.
Limitation of DNA evidence
This DAN data bank program owned by the FBI which operates on a local, State and National Level.
-Contains several different indexes
1 Forensic Index Solved and unsolved casework DNA profiles,
2 Offender index-DNA profiles from convicted Felons (qualifying offense vary by jurisdiction)
3 arrestee index-DNA profiles from arrested person (qualifying offense by jurisdiction)
-a hit is just investigative information. Involvement of the person with the case must be investigated.
-confirmation sample from the person must be submitted
CODIS
Handwriting , typewriting, indented writing, impression devices (rubber stamps/ dry seals), photocopies
Question documents
T/F Handwriting examinations can tell personality, age, sex or handedness of suspect
-Exemplars vs. standard
False
Paint, glass, fibers, fabric, ropes, cordage, hairs (animal & human), tapes, physical matches, impression evidence (footwear/tire tracks) (soil, adhesives, wood, feathers, leather, bone, matches)
-bloodstain pattern interpretation, digital image comparisons)
Trace Evidence
