Correct!!
what could be physical evidence? - ANSWERobjects that can:
- establish that a crimme has been committed
- make associations (crime to victim, victim to perpetrator)
recognition - ANSWER- of not just what but where
- situation of items relative to each other
where to start searching - ANSWERconsider paths of contamination from:
- perpetrator activity
- first responders
- emergency response
- look out for media interference
how do you search a crime scene? - ANSWER- lane/strip search
- line search
- circle/spiral search
- zone search
what are some other search tools? - ANSWERcanine units
metal detectors
heavy machinery
thermal imaging
ground penetrating radar
search method is based on factors such as: - ANSWER- indoor/outdoor
- size
- urgency
- lighting available
- what is being searched for
- what evidence was already found
- concentration of material
- people available
,lane/strip search - ANSWERgood for large areas
good for uneven terrain
line search limit - ANSWERmust remain in a super straight line with everyone else as you move
across crime scene, at the same pace
circle/spiral search benefits - ANSWERgood for locating additional items associated to an existing
piece of evidence
typically done indoors - too difficult to do outdoors
circle/spiral limits - ANSWERdifficult to stay in a perfect spiral path to ensure nothing is missed
zone search benefits - ANSWERgood for where other patterns won't work - typically in a house
divided by rooms - used where scene is already broken up into zones
how is evidence collection selective? - ANSWER- selectivity is determined by collector
- need knowledge about crime lab techniques, capabilities, limitations
- lack of this knowledge can lead to evidence being overlooked or collected improperly
why do you need a reference sample? - ANSWERto compare unknown samples to it
control/known samples include: - ANSWER- standard/reference - ex. hair/blood/DNA
- substrate control - ex. oil, carpet
- elimination samples
how do you prevent contamination? - ANSWER- use proper PPE
- clean tools between collection of different samples
- change gloves frequently
- package items separately to avoid cross contamination
things that are commonly used to collect evidence - ANSWER- plastic pill bottles
- manila envelopes
- tinfoil 'boats'
- cardboard pillboxes
- sealable plastic bags
- paper bags of various sizes
what is the druggist's fold used for? - ANSWERto collect trace evidence
what do you do with wet or bloodstained materials? - ANSWERair dry them before packaging and/or
place into paper bags so they have room to breathe and dry off
what should be done with items soiled with biological fluid that cannot be dried? - ANSWERshould
be placed in a cooler with ice packs
how do you seal packaged evidence? - ANSWERwith tamper-proof tape, then initial the seal
, how do you document evidence? - ANSWER- case number
- item number
- location
- name of collector
- date and time of discovery
- date and time of collection
- description of item
why might a sample not be submitted for analysis? - ANSWER- item type has low success
rate/expectation of obtaining reliable results
- not the most relevant to address allegations
- no probative value
- an individual is already associated with the item
- item has previously been tested for body fluids or fingerprints
sequential processing - ANSWERuse of as many developmental techniques as necessary to process a
piece of latent evidence, applying least invasive to most invasive
what are the systems in place to prioritize samples/cases? - ANSWER- severity of offense
- type of evidence
- probative value of evidence
- urgency/risks to public
what are the two types of DNA testing services at the CFS? - ANSWERhigh volume services and
violent crime services
what is the purpose of high volume services? - ANSWERfor lower severity situations, such as
breaking & entering, theft, drug, and weapon offenses
what are the three types of evidence accepted in high volume services? - ANSWER1) cigarette butts
2) cut-outs from envelope flaps
3) swabs of items suspected to have DNA
should you do presumptive tests prior to submitting evidence to high volume services? - ANSWERno
how many items can you submit to the high volume services per case? - ANSWERthree pieces of
evidence
types of swabs accepted to high volume services - ANSWER- swabs of suspected blood
- saliva swabs
- swabs of worn items
- handler swabs