FRSC242 Exam 3 studyguide focus

Is it okay to move a piece of evidence before it is fully documented?

No, cardinal rule no.1 clearly states that nothing gets moved or touched until it is photographed. once the evidence is moved, you cannot try to replicate where it’s original position was

When investigating a crime scene, you always start in the middle of the scene, and
then work your way to the boundaries of the scene. True or False?

false, start by clearing the largest target area possible and then narrow it down. starting in the middle risks contaminating evidence

list the general steps of a crime scene investigation chronologically

1. initial notification

2. approaching the scene

3. securing the scene

4. preliminary survey

5. evaluate physical evidence

6. narrative description

7. photograph the scene

8. sketch/diagram the scene

9. search the scene

10. record/collect physical evidence

11. conduct final survey

12. release and/or secure the scene

what is cardinal rule no.1?

nothing gets moved or touched until it is photographed

what is a crime scene?

the physical location where a crime occurred, including the paths of approach, flight, and all areas affected by the parties involved

where does a crime scene begin?

it begins where the actor turns intent into action, make sure to be careful approaching the scene

what is the first thing that should be done upon arriving at a crime scene?

secure the scene to prevent contamination, loss or alteration of evidence. entry log

what is the general rule of crime scene investigation?

clear the largest area possible first because it can always be narrowed down but not easily expanded later

what is cardinal rule no.1?

do not move/touch anything before it is photographed

what is cardinal rule no.2?

no unauthorized persons allowed at the scene RULE OF EXCLUSIVENESS

what is cardinal rule no.3?

document everything through either photos, video, sketches, notes

what is fixed location

extremely rare, all victims, evidence and actors are all at one location

what is multiple locations

most common, where crimes are against a persons and property, more than one scene. could show body moved or more

what materials should be available to you if you are trying to create a sketch of a crime scene?

measuring tape, compass, p[aper, pencils, evidence markers, legend/key

elaborate on hypothetical situations, for ex, why could a cigarette butt be important?

could contain DNA to someone related to the crime scene

elaborate on hypothetical situations, for ex, open window/ curtain importance?

could show entry/exit points

elaborate on hypothetical situations, for ex, bullet casing importance?

could determine weapon type and trajectory

name the elements of a crime scene sketch that contributes to it being good and effective

directional compass, measurements, fixed objects, evidence markers, legend/key

what are the types of sketches

• locality

• grounds

• building

• location

what are sketching methods

rectangular coordinate, baseline coordinate method, transecting baseline method, compass point method, elevation method, triangulation, polar coordinate, secondary reference point method

be able to look at a sketch and know which one it is referring to

:)

what is the purpose of crime scene sketching?

• provide perspective

• help visualize spatial relationships

• supplement photos for court if photos are too graphic

what are the 4 steps of crime scene photography

1. overview photographs

2. medium-range photographs

3. close-up photographs

4. evidentiary photographs

what is thee crime scene security preserve and protect rule?

make sure to prevent loss, contamination and alteration

why should you photograph a crime scene

• help to reconstruct the scene if needed

• creates a permanent visual record

• present evidence in court

what should a photographer be thinking about when photographing a crime scene?

• avoid moving evidence

• capture overall to specific views

• think ab out lighting, ocus, scale, and keeping maximum of depth of field

• “witness eyelevel”

what depth of field is ideal for photographing a crime scene?

maximum depth of field (best sharpness and across entire image)

can photography be used to document any other things?

yes, document the deceased, the trace evidence like peoples shoe impressions, injuries on body, tire impressions

why does the chain of custody exist? why does it matter?

it shows who had control of evidence from time of collection to time of court

it prevents loss, contamination and alteration

what are the two main types of lighting?

-natural

-artificial

what subtopics are there for natural lighting?

• full sun aka harsh shadows

• overcast aka even diffused light

what subtopics are there for artificial light?

• flash unit

• flashlight/floodlight

define front lighting

light covers the subject evenly, allowing for consistently good exposure

define side lighting

provides a greater sense of depth, shape and dimension due to shadowing, aka oblique lighting

define back lighting

produces silhouettes and can fool a camera meter, resulting in incorrect exposures

• there is no use for back lighting in forensic photography

what is a camera?

a light tight box with an opening in the front and light sensitive material in the back

what are the basic components of a camera?

• aperture, controls light

• shutter speed, controls exposure time

• ISO, controls sensitivity to light

• lens, focuses the image

• storage medium, where the photos are saved

define physical integrity

preserving the scene exactly as found

define prevent defense

securing the scene to prevent contamination, loss or alteration

define perimeter

outer boundary of a crime scene

define physical evidence

tangible items linking suspect, victim and crime

define camera

light tight box with an opening in the front and light sensitive material in the back

define key/legend

part of a sketch explaining symbols used

define GIS

Geographic Information System; mapping and analyzing spatial data

define legal integrity

maintaining proper handling of evidence for court

define chain of custody

documentation showing who handled evidence from collection to trial

define locard’s exchange principle

-theory of transfer

• every contact leaves a trace

define photography

capturing images using light

phos - light

graphos - write

to write and draw with light

define testimonial evidence

evidence obtained by talking to witnesses, victims, or suspects