PSYC 3P53 Lecture Notes - Lecture 5: Police Lineup, Facial Composite, Recognition Memory
26 Apr 2018
School
Department
Course
Professor
Eyewitness Testimony
Outline of Sections
• Memory and eyewitness research
• Recall procedures
• Recognition procedures
• Estimator variables and guidelines
Section 1: Memory and Eyewitness Research
Memory
• Memory is not like a video recorder, this process only allows
us to remember what we have encoded
Types of Memory
• Two types of memory retrieval :
• Recall Memory: Reporting details of previously
witnessed event/person
o Asked what the suspect looked like, what they
were wearing, etc based on what they saw
o Retrieving memories without cues
• Recognition Memory: Reporting whether current
information is the same as previous hear/ seen
information (e.g., lineups)
o Comparing an object in front of you with what is in
memory and seeing if they match (you see the person so with cues)
o Ex. Asked to pick someone out of a photo line up
Eyewitness Research
• Variety of research methods:
• Archival data
o Data from actual crimes
o Police files
find more resources at oneclass.com
find more resources at oneclass.com
• Naturalistic environments
o Accompanying police to crime scene and conducting interviews after the
police have conducted theirs
• Laboratory simulations
o Most common because they are easier to do
o Can control variables with regards to memories and effecting them
• Ex. Participants are asked to witness a critical event such as a crime
through a video or re-enactment, and they are typically unaware that
they will be asked about this or the details of this afterward
• They are then either asked questions, asked to pick a suspect out of
the line up, etc
Independent Variables
• Factors that are manipulated or changed
• Two types of independent variables:
o Estimator variables: Variables that cannot be changed (age of witness,
lighting, age, time etc.)
• Present/ occurred at the time of the crime
o System variables: Variables that can vary (questioning techniques,
lineup procedure, etc.)
• Can be manipulated to increase/decrease witness accuracy
• Type of procedure used to interview the witness
• Line up procedure used to present suspect to the witness
• In real life are under the control of the justice system
o Both can be studied and manipulated in lab studies, but in the real world
only system variables can be manipulated, so we focus on these
Dependent Variables
Three types of dependent variables:
o Recall of the event
• Usually a crime
o Recall of the perpetrator
• What do they look like, what were they wearing, etc
o Recognition of the culprit
• Lineup, voice identification, etc
find more resources at oneclass.com
find more resources at oneclass.com
Recall of the Event
Two forms of recall:
• Open Ended: Recount without being prompted
o Write out or orally say all they can remember from the crime scene
o No prompts
o To get an initial unbiased account of the event
• Direct Question: Witnesses asked specific questions
o About crime/ aspects of crime
o Ex. What kind of car, what colour, etc
• Usually start with open ended and then move into direct question
Examining Recall Information
Amount of Information
• How many descriptors of the crime/ culprit etc did they give
Type of Information
• How many central details (actually related) to the crime vs how many
peripheral details
Accuracy of the Information
• Most important
• How many correct descriptors
• How much was failed to or falsely reported
Recognition Information
Typically police lineup
• Photos, voice, etc.
Accuracy
• Did they correctly identify or…
• Did they correctly state they are not in the lineup at all
Type of Errors
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Outline of sections: memory and eyewitness research, recall procedures, recognition procedures, estimator variables and guidelines. Memory: memory is not like a video recorder, this process only allows us to remember what we have encoded. Asked to pick someone out of a photo line up. In real life are under the control of the justice system: both can be studied and manipulated in lab studies, but in the real world only system variables can be manipulated, so we focus on these. Three types of dependent variables: recall of the event, usually a crime, recall of the perpetrator, what do they look like, what were they wearing, etc, recognition of the culprit, lineup, voice identification, etc. What kind of car, what colour, etc: usually start with open ended and then move into direct question. Amount of information: how many descriptors of the crime/ culprit etc did they give.
