Unit 2: CSI Flashcards
What is the goal of a crime scene investigation?
The goal is to recognize, document, and collect evidence at the scene of a crime. Solving a crime crime will depend on piecing together the evidence to form a picture of what happened at the crime scene.
Dr. Edmond Locard
Every criminal can be connected to a crime by small particles carried from the scene
What is the Locard Exchange?
It is whenever two objects come into contact with one another, a cross-transfer of physicals evidence can occur. eg. someone rubs up against flower exchange of pollen, or if someone touches a glass then they will transfer their fingerprints
What are two types of evidence?
- Direct evidence: first hand observations (direct) ex. eyewitness, videos, confessions)
- Circumstantial evidence (may not always bring a suspect): Indirect evidence that can be used to imply a fact but does not directly prove it. Example: finding a suspects gun at a crime scene is circumstantial evidence that they suspect was there
Types of Circumstantial Evidence…
- Physical Evidence: synthetic fibres, weapons, bullets, shell casings, paint chips, documents, imprints and prints (shoes, tires, etc.), took marks, soil, drugs, etc.
- Biological evidence: body or body parts, body fluids, hair, leaves or other plant parts, natural fibres, feathers, wood
- Trace evidence: small but measurable amount of physical or biological material found at a crime scene. ex. strand of hair, fingerprint, DNA, drop of blood, pollen, gunshot residue
Class Evidence
It narrows evidence to a group of persons or things i.e blood types: can be A, B, AB, O. Finding one type at a crime scene narrows down the suspects to a smaller group
Individual Evidence
Narrows evidence down to a single person or thing ex. fingerprints, handwriting, DNA, and sometimes physical matches
What are the three types of evidence for bloody fingerprints
Direct or CIRCUMSTANTIAL
Physical or BIOLOGICAL
Class or INDIVIDUAL
Importance of Evidence
- Can prove a crime has been committed and set the scene for the investigation
- Can back up witness testimony or prove it false
- Can link a suspect with a victim or with a crime scene
- Can determine the identity of people associated with a crime
- Allows investigators to reconstruct a crime
ex. blood splatter may show where suspect and victim were in relation to one another and indicate what happened in what order
The CSI team includes…
- First police officer on the scene
- Backup police and possibly a district attorney
- Medics
- Investigator/ Detective
- Medical Examiner
- Photographer and/or Field Evidence Technician
- Lab experts
What are the 7 S’s of CSI?
- Secure the scene
- Separate the Witnesses
- Scan the scene
- See the scene
- Sketch the scene
- Search for evidence
- Secure and collect evidence
What is the Innocence Project?
Created to reexamine post-conviction cases (especially in regards to eye witness testimony)
Eyewitness misidentification
Mistaken identifications are the leading factor in wrongful convictions
Double-blind Procedure
A “Double-blind” line-up is one in which neither the administrator nor the witness knows who the suspect is. This prevents the administrator of the lineup from providing inadvertent or intentional verbal or nonverbal cues to influence the eyewitness to pick the suspect
What is Sequential Presentation of Lineups?
When combined with a “blind” administrator, presenting lineup members one-by-one (sequentially), rather than all at once (simultaneously) has been proven to increase the overall accuracy of eyewitness identifications
What are instructions?
Instructions are a series of statements issued by lineup administrator to the eyewitness to deter the eyewitness from feeling compelled to make a selection. They also prevent the eyewitness from looking to the lineup administrator for feedback during the identification procedure. One of the recommended instructions includes the directive that the suspect may or may not be present in the lineup
How does one compose a lineup?
Suspect photographs should be selected that do not bring unreasonable attention to the suspect. Non-suspect photographs and/or live lineup members (fillers) should be selected so that the suspect does not stand out from among the other fillers. Law enforcement should select fillers using a blended approach that considers the fillers’ resemblance to the description provided by the eyewitness and their resemblance to the police suspect
What is a confidence statement?
Immediately following the lineup procedure, the eyewitness should provide a statement, in their own words, that articulates the love of confidence they have in the identification made
What is a primary crime scene?
Where a crime has actually occured
What is a secondary crime scene?
In some way related to the crime but is not where the actual crime took place
Different types of searching for evidence
A pattern should be walked and location of evidence marked, photographed and sketched
- Spiral
- Grid
- Quadrant or zone
- Linear
Does all evidence have to be properly packaged, using specific techniques and procedures
True
Can you just pickup evidence with your hands
False; metal or plastic forceps may have to be used to pick up small items
What is used for hairs, glass, fibres, or other kinds of trace evidence
Plastic pill bottles with lids
What should you use for liquids and arson remains
Airtight unbreakable containers
How would you keep blood stained materials
In wrapping paper, manila envelopes, or paper bags to prevent the growth of mold which can destroy the evidential value of blood. Air must be able to flow around the evidence to prevent moisture buildup
Where should charred debris from a fire must be contained where?
In an airtight container such as new metal paint cans, to prevent any volatile petroleum residues from evaporating. This could be evidence of arson
What 2 things do you need when collecting evidence
- Chain of custody
- A list of all persons who came into possession of an item of evidence - Evidence log
- Description of evidence, name of suspect, name of victim, date and time of recovery, signature of person recovering the evidence etc
Do you need to make sure chain of custody is documented in order for it to become admissible in court?
True
What are control samples?
Control samples should also be taken from the victim for the purposes of exclusion (blood, hair, etc)
What is a standard/reference sample?
Physical evidence whose origin is known, such as blood or hair from a suspect that can be compared to crime-scene evidence
What is a buccal sample?
Cheek swab
Are lab results sent to the victims family
False; they are sent to the lead detective
Do forensic lab technicians process more than one type of evidence like CSI shows?
False; they process only one type of evidence
What do crime scene reconstruction allow?
It allows the detectives to form a hypothesis of the sequence of events from before the crime was committed through its commission
Does evidence lie?
Fasle; but it can be staged
What should one do to determine if a crime scene is staged?
- Treat all death investigations as homicides
- Do the types of wounds on the victim match the weapon?
- Could the wounds be easily self- inflicted?
- Evaluate the behaviour (mood and actions) of the victim before the event
… etc
Any removal of evidence from a crime scene must be removed from a crime scene in accordance with the Criminal Code of Canada
True
What are the 2 parts to a search warrant request?
- The actual warrant itself
- The affidavit or the law enforcement officer which sets forth the facts as to why the search warrant should be granted
What is a Hobbs Sealing Request
Means that the police agent conducting the search warrant wants to keep all or any part of search warrant affidavit from being revealed so as to proceed an informants identity
A warrantless search can be conducted if…
- Under emergency circumstances (danger to life or limb)
- If there is immediate danger of the loss or destruction of evidence
- If there is probable cause- the search of a person and their immediate property in conjunction with a lawful arrest
- With the consent of the involved parties
Kyle Unger… crime details, cause for conviction, time spent in prison, cause for exoneration
- Was charged for the murder of a 16 year old girl named Brigitte Grenier
- Hair follicle
- 14 years
- Hair follicle was not his DNA
What is testimonial evidence?
What is said in court by a competent individual during their testimony such as witness speaking out to the court to inform the judge of what he or see had seen to maybe declare the defendant guilty or innocent
ex. a witness testimony that has been deemed to be correct by the terms of the judge
What is physical evidence?
An object or material relevant to the crime at hand and was more or less likely found at the crime scene for accuracy purposes
ex. fingerprints, footprints, tire tracks, blood etc
What is evidence?
One of the basic foundations of any criminal or civil proceeding
What are common types of evidence?
Real, documentary, demonstrative and testimonial
What does testimonial evidence help with
Testimonial evidence enables investigators to recreate a crime scene or develop a series of events as they occurred
What makes evidence considered material?
If it is presented to prove a fact which is an issues in the court case
ex. if the issue is a breach of contract, a witness whose evidence proves it was raining when both parties signed the contract is relevant but immaterial would be material if it proves that the defendant did not preform obligations
What makes evidence considered relevant?
If it tends to increase or decrease the probability of what is introduced to disprove or prove
ex. if evidence seeks to prove the accused bit the plaintiffs nose during a fight while an eye witness testimony would be deemed relevant
What makes evidence considered to be competent?
If what is being presented meets some basic conditions of reliability. The showing that such evidence satisfies those tests or any conditions of admissibility is known as foundational evidence
ex. when the conflicting side objects that the response to a thing, document, or question is without sufficient foundation, they are actually saying that the evidence is not competent
What are the requirements to make someone a competent witness?
- They must be under oath or any similar substitute
- They must be knowledgable about what they are going to testify. This means they must have perceived something with their senses that applies to the case in question
- They must have a recollection of what they perceive
- They must be in a position to relate what they communicated
Why is testimonial evidence different from other types of evidence
It is one of the only forms of proof the does not need reinforcing evidence for it to be admissible in court
Blood, hairs, fibers, soil particles should not be removed from garments, weapons, or other articles of clothing
True
Should you package items together
False; items should be sent separately
What is “identification” of evidence
Is the process of determining a substances physical or chemical identity
What is an observation? Why is it important?
An observation is the action of closely observing or monitoring something or someone, and its important to begin making assumptions of what happened
What is the Chain of Custody?
Chronological documentation of paper trail that records the sequence of custody, control, transfer, analysis and disposition of materials
What is beyond reasonable doubt
Prosecutor must prove “____”, innocent until proven guilty
What is considered a fact?
Something that can be proven
