Criminal Investigation
Crime Scene Processing
Part 10
Crime Scene
1.
Evidence
- most crimes
- to identify
- to convict
a. Reproduce the crime
- evidence collection
- forgery / shoplift: no crime scene
b. Prepare while enroute
- observant / mental notes
Scene, cont.
(1) Check for suspect
- officer protection
(2) Injuries to victim
- medics / pronounce dead
(3) Call for assistance
- additional officers / experts
b. Protect scene
- neighbors / officers / news / medics
Scene, cont.
- guided through
(1) First officer
- in charge until relieved
(2) Building search
- two officers
- stay together
(3) Protection methods
- vehicles to block streets / alleys / etc
Scene, cont.
- officers at certain points
- police tape
(4) Information in report
- necessary for court
- defense attorney
2.
Crime scene search
- probative value
- items of no value
Search, cont.
a. Basic function
- thorough / legal
- evidence present
(1) Goal of search
- crime occurred / type
- when committed
- identify who
- how committed
- suggest why (motive)
Search, cont.
(2) Do not search until:
- photo / sketching complete
- conduct walk-through / mental picture
b. Photography
- important role
- court presentation
(1) Picture / video
- accurately represents
- immediate / kept in roll
Search, cont.
(2) Equipment
- instamatic
- Polaroid
- Press cameras (35mm)
- fingerprint camera (1 x 1)
- movie / videotape
- specialized cameras
(3) Lens / filters
- wide angle / fisheye / telephoto / micro
- eliminate colors
Search, cont.
(4) Film
- black and white / color / infrared
- ASA: speed of film
3.
What to photograph
- general areas
- specific locations
- objects of evidence
a. Long-range pictures
- take of locality
Search, cont.
- suspect’s entry / exit
(1) Entry to property
- doors / gates / etc
(2) Exterior
- buildings / grounds
(3) Identification shots
- street sign / house numbers
- other identifiable structures
Search, cont.
b. Medium-range pictures
- immediate crime scene
- objects of evidence
c. Close-range pictures
- entire surfaces (bullet hole / chair / table / etc.)
- specific (hair / fiber / blood / finger-footprint)
(1) Several shots
- different locations
- do not disturb
Search, cont.
d. Instant photos
- bruises / wounds
- vandalism
- photo array
4.
Properly performed
- most valuable aids
- little expertise
- become familiar
- basic class
Photos
a. Investigative photographs
- any made to record object / event
- clarify a point
(1) Photo laboratory
- greater enhancement
b. Admissibility
- if investigator can testify
- accurately depict
- area he/she observed
Photos
(1) Accuracy
- degree it represents appearance
- form / tone / color / scale
(2) Camera lens
- not pickup perspective / scale / distance
- supported: sketch / investigative notes
- ruler / scale measurement
(3) Negative
- sufficient proof / refute allegations
Photos
c. Highest quality of evidence
- depict scene precisely
- as found
(1) Exclusive function
- no people working in scene
- no police equipment
d. ID of photographs
- precisely identified
- data noted on each shot taken
Photos
(1) Technical history of photo
- recorded in notes
- how relates
- permanent part of case
e. Custody
- establish chain of evidence
(1) Who took photos
- primary / lab technician
Photos
(2) Who maintained the film
- evidence locker
- case file
- locked desk
(3) Who developed
- police crime lab
- commercial processor: mail/return receipts
(4) Who maintained pictures
- detective / evidence technician?
Photos
f. Admissibility
- material / relevant / competent
(1) Material
- relates to the case
(2) Relevant
- assists or explains testimony
(3) Competent
- represents what it purports
Photos
- properly identified
- follows chain of evidence
5.
General considerations
- time: an essential factor
- preempt other aspects of investigation
a. Cannot be moved / examined
- until photographed
- all angles
Photos
(1) Undergoes significant change
- passage of time
(2) Photo ASAP
b. Camera positions
- recorded on crime scene sketch
(1) Measure distance
- immoveable object
- vertical line / from camera lens
Photos
(2) Interior scenes
- depict as a whole
- move in closer
- specific object

Marking devices
- used in the field of view
a. Rulers
- good method
- relationship of objects
Devices
b. Identifying letters
- A / B / C / etc.
- used to describe items of evidence
- letter ‘A’ next to bullet hole
- shown in notes / reports
c. Similar marking devices
- chalk marks / string / etc.
(1) Can be contested
- not truly represent original scene
Devices
(2) Two photographs
- one with marking device
- one without
7.
Types of photographs
a. Victims
(1) All possible angles
- impossible to “over-photograph”
- controlled / protected crime scene
Types
(2) Obtain: body part not visible
- back of body
- if found on back
b. Witnesses
- same approximate location
(1) Statement from witness
(2) Review at trial
- help from being confused
Type
c. Clothing
- description recorded
- before moving body
(1) Clothing removed
- photograph where found
- accurate measurements taken
d. Weapons
- photo where found
- before moving
Type
(1) Unable to photo
- take of general area
- notes taken: allow accurate testimony
e. Bloody areas
- colored photos
- large concentrations / small bloodspots
(1) Include ruler (2nd photo)
- bloody drag marks
- photo completely
Type
(2) Photo any / all clothing
- boot / shoe
- ruler next to
(3) Notes at time
- direction blood was traveling
- approximate size of spots
f. Scrape / drag marks
- all that show a struggle
- bent grass / heel marks in sand
Type
(2) Important role
- what actually happened
- before / during / after
g. Impressions
- tire / shoe / boot
- fabric on dirt / paint / dust
- ruler: oblique lighting
h. Other articles
- bottles / glasses / cups / playing cards / etc.
Type
(1) No object should be moved
- until photographed
- original location
8.
Most important element
- maintaining perspective
a. Viewed from particular point
- relative position / size
b. Any distortion
Type
c. Natural perspective
- aiming camera at 90 degree angle
- opposite wall
- outdoors: fixed object
d. Keep at eye level
- unless tripod
- viewer can see at eye level
e. Overlapping segments
- one direction around the room / area
Type
9.
Critical photographic requirements
a. Approaches to the scene
b, Surrounding areas
c. Close-up: entrance / exit
d. General scenario shot
e. Minimum: 2 photos of body / 90 degree angles
Type
f. Body close-ups
g. After removal of body
h. Fingerprints
i. Blood stains
j. All items of evidence