chapter 2 Flashcards
Responsibilities of 1st Officer:
Acquiring medical assistance for injured victims
Detaining any potential suspects or witnesses
Securing crime scene to greatest extent possible
Calling for additional personnel needed (other officers and/or forensic investigators)
how is crime scene secured? what should you include in the scene?
crime-scene tape, ropes, and/or traffic cones
Include an area where crime took place and surrounding area where physical evidence may be located
how do you keep track of personnel at crime scene?
log of personnel movements in and out of crime scene (names and times)
what are the 3 methods of recording the crime scene?
photograph
sketch
notes
what are the key elements of photographing the crime scene?
Objects must not be moved until they’ve been photographed from all necessary angles (unless injured parties)
Where crime actually occurred + adjacent important areas
what is the most important part about how crime scenes are photographed?
crime scene is unaltered
what must the photographs include?
points of entry/exit, each wall and adjacent area, body position + location to crime, and close-ups for details (ruler for scale)
when do notes at the scene begin?
when an investigator arrives at the scene
what should notes begin with?
who contacted investigator, time of contact + arrival at scene, preliminary case info., and personal present on arrival and those being contacted
what do notes contain
personal log, all observations made by investigator and what time
in what format are notes taken?
Taken in uniform layout as observations are made
Written in bound notebook in blue or black ink
what does the lead investigator do
start evaluation process
3 steps of arriving at the crime scene
Boundaries of scene must be determined
Establish of perp’s path of entry/exit
Initial walk through of scene
(Gain overview of situation, Develop strategy for systematic examination and documentation of entire crime scene)
how can you prevent bias at the scene?
no pertinent evidence can be overlooked (thorough + systematic evaluation)
what does the search depend on?
location and size of area as well as suspects and victims at scene
direct evidence
1st hand observations, eyewitnesses, video, confessions
circumstantial evidence
Implies fact, but does not directly prove it
class evidence
object that has characteristics common to a group of similar objects
individual evidence
object with a really high probability of being linked to one source
JonBenet Ramsey evidence
biological samples from the scene could help identify or exclude potential suspects, analysis of fingerprints on various objects could provide leads on intruders or family members, hair and fiber analysis could link suspects to the scene or establish a timeline of events, and examining any digital evidence for communication could uncover motives or threats
JonBenet Ramsey errors
Friends and family were allowed to enter the crime scene, compromising potential evidence. JonBenét’s body was carried downstairs by her father, before investigators arrived.
Important forensic evidence may have been overlooked or contaminated due to a lack of immediate and proper procedures.
Physical Evidence
encompasses any and all objects that can establish that a crime has been committed
Provide a link between a crime and its victim, or a crime and its perp.
Effective only when 1st used a crime scene
Anything from massive objects to microscopic traces
packaging evidence
Dry wet evidence prior to packaging to prevent mold.
Allow for air circulation (paper).
No plastic bags, sealed tubes, or jars (unless it is tissue, tox samples, or arson evidence).
Biological items should be dried and kept in the freezer.
Package separately.
Minimal handling - avoid talking/coughing over evidence.
Tape seal package with initials before leaving scene.
evidence must be handled with
gloves or forceps
how should you package the evidence?
must be placed in appropriate container for storage
Separate bags with labels, and obtain standards/reference samples for later comparison
chain of custody
written list of all people that came into contact with that evidence
details about the woodchipper case
Victim: Helle Craft
Suspect: Richard Craft
Relationship: Married, Witness: Neighbor and friends
Expert: Dr. Henry Lee (director of forensic science in Connecticut), and Dr. Levine named the body as Helle by the leftover teeth)
Evidence: Red blood cells found on the bed where Helle was said to be murdered (biology) and human remains including; bones (anthropology), hair (biology), fingernail polish (physical science), part of a finger (biology).
