The trouble with try to remember them as best you can. eyewitness testimony...
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The trouble with eyewitness testimony
April 1, 2008 Dana Roark, Ph.D.
Begin with a demo….
Look carefully at the following faces and try to remember them as best you can….
End ….test later!
Again, DNA frees a convict 12:02 AM CST on Tuesday, October 31, 2006
By ROBERT THARP / The Dallas Morning News
DNA testing is unlocking prison doors for another wrongfully convicted Dallas man on Tuesday, bringing to 10 the number of felony exonerations in the county after such tests in the last five years.
After maintaining his innocence for more than 25 years, Larry Fuller, 58, is expected to be released from custody without any opposition from prosecutors after an afternoon hearing. He was convicted of aggravated rape in 1981 and sentenced to 50 years in prison based on a sexual assault victim's identification of him.
The woman initially told police that she could not provide a detailed description of the man beyond a vague idea of his skin tone, race and height. The attack occurred about an hour before sunrise, and the only light in the room came from a window and the dial from a small clock radio.
About a week after the attack, a detective showed the woman photos of six men, including an image of Mr. Fuller.
The woman told police that Mr. Fuller's photo "looks a lot like the guy," but she was not positive.
A detective returned a few days later with another photo lineup that included a more recent photo of Mr. Fuller with a beard. The woman identified Mr. Fuller's image but said she did not think her attacker had facial hair.
During Mr. Fuller's trial, the victim testified that she was certain he was the man who raped her.
Jurors deliberated 35 minutes before returning a guilty verdict.
Mistaken eyewitness identifications account for up to 80% of all wrongful convictions (Scheck, Neufeld, & Dwyer, 2001)
Juries find eyewitness testimony very compelling…especially when it is offered with a high level of confidence.
“There is almost nothing more convincing than a live human being who takes the stand, points a finger at the defendant, and says “That’s the one!”---Elizabeth Loftus, 1979
Research has shown no correlation between accuracy and confidence of eyewitnesses (Smith, Kassin, & Ellsworth 1989)
The perils of line-ups (Busey & Loftus, 2007)
Culprit presented along with 5 fillers who fit the description… Live or photographs
Challenge is to administer an identification procedure that is unbiased An innocent suspect has no greater chance of
being identified than do the fillers
4 main ways line-ups can be biased (Busey & Loftus, 2007)
Physical bias: fillers don’t fit the witness description For example….”White male with gap between teeth”
If fillers don’t fit, then then functional size of line-up is reduced
Physical bias: oddball Suspects picture is physically different from the fillers’
Larger, smaller, different background, different clothing, etc.
•Real example of line-up used in Tacoma, WA •Suspect chosen by participants 26% of the time (chance = 17%) •Oddball effect is problematic even if it is very subtle
4 main ways line-ups can be biased (cont.) (Busey & Loftus, 2007)
Lack of double blind procedures Police officer conducting the line-up shouldn’t
know the who the suspect is Rarely done in practice Officer may inadvertently lead the witness…. “Is
there anyone else you think it might be?”
Unconscious transference Witness has viewed the suspect at some time
other than at the crime live in the same neighborhood
Familiarity may bias identification
Eyewitnesses make errors if they have been pressured to provide a specific answer (Roebers & Schneider, 2000) “Exactly when did you first see the suspect?” Pressure to come up with a memory
More accurate testimony if (Roediger & McDermott, 2000): people are allowed to report in their own words given sufficient time allowed to say, “I don’t know.”
Eyewitness compliance ---eagerness to please (Ost et al., 2002) “Did you see the television fragments of 1997 fatal crash
Dianna, Princess of Whales?” 44% said yes, although no footage of this event exists!
The effect of positive feedback
Errors are more likely if suspects have been given positive feedback (Wells & Bradfield, 1998) “Is it number 3?” “Good, you identified the suspect.” Even a simple “okay” can be enough to make
participants report during trial that they are “very sure” A little corroboration is a powerful thing Even if during the line-up they took 30 minutes to make a
Witnesses talking to one another right after the incident
The “I-never-forget-a-face” idea
Only partly true
Familiar faces vs. unfamiliar faces
People are very good at recognizing faces they know well…
People are very poor at recognizing faces they’ve seen only briefly or met only recently new classmates bank teller, etc.
Why? the same face can look very different under
different viewing conditions lighting changes different expression different viewpoints, etc.
Here comes your face recognition test…
OLD or NEW? OLD
OLD or NEW? NEW
OLD or NEW? NEW
OLD or NEW? OLD
•Face recognition can be quite difficult if the learning and test images are very different, image- wise….
•Unfamiliar face recognition is a much different kind of task than recognizing people you know well
•such as an old friend or family relative……
10 very different images of (ex) P.M. Tony Blair
20 very different images of Paul McCartney
The suspect Do you think you could recognize this person from a line-up?
What factors would make it easier or harder?
Other perceptual factors
viewing time lighting conditions degree of focused attention cross-racial effects distance of the viewer (example)
A 1997 murder case in Alaska involving the murder of a teenage boy, resulted in the trial of 2 suspects.
The centerpiece of the prosecution’s case was the testimony of Arlo Olson, who, while drunk, had seen the perpetrators at night and from a distance of 450 ft.
The defense lawyers called upon Geoffrey Loftus as an expert witness to educate the jury about:
1. perceptual problems of memorizing suspects
2. why Mr. Olson would have chosen the suspects from the line-ups
3. how it was possible to have a clear, confident memory that was false
resizing the image
Equivalent representations of a face viewed from different distances
blurring the image
Simulated distance of a face viewed from 450 feet away
Lessons from eyewitness suggestibility
Memories are malleable A synthesis, not a video tape
Memories can change based on what we read, see, and are told
Source confusions are common Being told about something vs. remembering something
Psychological science has yet to determine a reliable method for telling whether a memory is true or false
Extremely vivid, long lasting memories for unexpected, emotionally laden and consequential events
9-11 OJ Simpson verdict Kennedy assassination
Are these memories more accurate than everyday memories?
Actual: NO Perceived accuracy: YES
9/11 research (Talarico & Rubin, 2003)
Interviewed participants Sept 12
Also asked about an “everyday memory”
When did you first hear the news?
Who first told you the information?
Re-interviewed 7, 42, or 242 days later for both types of memories
But no increase in accuracy for flashbulb vs. everyday memories
The act of retrieving a memory often leads to distortions
Retelling the story
Can help via rehearsal processes
But can also lead to insertions that become incorporated into a memory for an event
Memory is a “constructive” process
Impossible memories can be implanted with strong suggestion (Loftus, 1995, 1997)
“You’re family told us about this event”
Lost in the mall Rescued by a lifeguard Spilled punchbowl at a wedding
Misleading post-event information
Loftus, 1979 •Participants view one of two slides •Afterwards given either consistent or inconsistent information •Then asked to identify which picture they originally saw •75% accuracy when given consistent information •41% accuracy with inconsistent information
“Tell me everything you can remember about this event, no matter how trivial” (Wade et al., 2002) 50% partially or clearly recalled the even