133 terms

Psyc 162 Midterm 2


Terms in this set (...)

Memory is ...
-While tapping our memories, we filter or fill in missing pieces of information to make our recall more coherent
Misinformation effect:
incorporating misleading information into one's memory of an event
Hit versus smashed what asked about speed
-Then asked about broken glass at the scene
-Smashed versus hit -- smashed reported glass more
-Elizabeth Loftus experiment?
-Change of word changes speed estimate -- and what they remembered could potentially be used in court
Recovered Memory Epidemic
-Unfolded in 1990's
-In therapy, adult victims recover memories of having been abused during childhood
-Charges brought against incredulous parents
-Guilty verdict
The Courage to Heal
-Published in 1988
-Guide for women of survivors of sexual abuse
-Made assersitions as if they were scientifically true -- influential with therapists
Theory behind psychotherapy for repressed memories
-Certain memories are too painful to bear
-As a defense mechanism, those memories are repressed
-Repressed memories create psychology disorders
Therapeutic Methods
-Assigned reading of self-help books
-Dream analysis
-Guided imagery
Wade, Garry and Lindsay experiment:
-Using false photographs to create false childhood memories
-Digitized photos of 3 true events childhood -- took photos of family members and pasted them into false photo of hot air balloon
-Interviewed family member three separate times about those 4 events (tell every detail)
-Everyone remembered the true events -- 30% remembered false balloon ride
-After 3 interviews almost 50% remembered false memory
Linda Williams Study
-1994 -- recall of childhood trauma
-Participants: 129 adult women who had been evaluated in early 1970's for possible sexual abuse
-Method: participants were interviewed about possible traumatic experiences during childhood
-40/129 did not describe an episode of sexaul abuse
-long periods with no memory of abuse should not be regarded as evidence that the abuse did not occur
Critique of Williams study
-Unwillingness to report childhood sexual trauma to an unfamiliar interviewers does not mean that the trauma was forgotten
-Some of the abuse took place when the women were as young as 10 months (infantile amnesia)
-Some of the abuse was such that the child might not have recognized it as such
What the False Memory debate taught us about memory
-False memories are surprisingly easy to implant
-What makes them so east to implant is that memories are reconstructive
Proponents (recovered memories are real)
-15% of adult women who report memory for childhood abuse also report having forgotten about that at some point
-None of these women recovered their memories in therapy
Opponents (recovered memories are false)
-False memories are extremely easy to implant, so it does not make sense to convict anyone without corroborating evidence
Since the 1990s, DNA testing has overturned more than
350 wrongful convictions of the innocent
Of the 350 wrongful convictions, how many were due to eyewitness misidentifications?
The Case of Ronald Cotton
-In 1984, a college student named Jennifer Thompson was raped
-Shortly thereafter she picked Ronald Cotton out of a photo lineup (said she was certain)
- Cotton was sentenced to life in prison plus 54 years, and he served almost 11 years in jail before being exonerated by DNA testing
The National Registry of Exonerations
-20 or so per year (DNA exonerations)
-But there are a lot of other ways to be exonerated
-DNA isn't the only way to get them out
-Purgeory and false accusations and Official Misconduct
Research has shown that sequential lineups
reduce misidentifications and increase accuracy compared to traditional simultaneous lineups
Lineup Construction and Lineup Fairness
-A lineup should contain only 1 suspect
-The suspect should match the physical description provided by the eyewitness
-The police should have some additional reason for believing that the suspect may have committed the crime
-All of the fillers (aka "foils") should also match the physical description provided by the eyewitness (i.e., the suspect should not stand out)
If a non-witness can identify the suspect from the description alone then
the lineup is unfair
Simultaneous lineup
show pictures simultaneously, all at once
Sequential Lineup
one picture at a time
Mock-Crime Laboratory Studies
-Each participant (n = 200) watches a simulated crime (e.g., a video of a young man stealing a laptop)
-Followed by a lineup memory test:
-Half (n = 100) are then tested using a target-present lineup
-The other half (n = 100) are tested using a target-absent lineup
Lindsay & Wells (1985)
- Simultaneous versus Sequential lineups
- Huge drop in False ID rate with sequential lineup
2013 Survey of US Police Departments
-30% adopted sequential procedure
-Huge impact of psychological research
Absolute vs. Relative Judgments
1. Simultaneous lineup
-Eyewitnesses feel "pressure to choose" and therefore rely on a relative judgment (choose the most familiar lineup member)
-Alternative way of thinking: eyewitness use a lower standard for making an ID

2. Sequential lineup
-Eyewitnesses feel less pressure to choose, so they rely on an absolute judgment (choose a lineup member only if the match to memory is good enough)
-Alternative way of thinking: eyewitness use a higher standard for making an ID
Reduce "pressure to choose" by inducing a more
conservative standard
Conservative approach means
fewer ID's (both false and correct)
A higher ROC curve indicates
greater discriminability
The Concept of Response Bias
-Do not make an ID if you are just guessing
-Do not make an ID unless you are reasonably sure
-Do not make an ID unless you are very sure
-Do not make an ID unless you are absolutely certain
More than One Way to Perform ROC Analysis
-Manipulate response bias across conditions, using instructions to vary the degree of confidence the witness should have before making an ID from the lineup
-Collect confidence ratings from eyewitnesses who make an ID and vary the requisite level of confidence after the fact
To compute the most "liberal" ROC point,
count all suspect IDs (including guesses)
To compute the most "conservative" ROC point,
count only suspect IDs made with the highest level of confidence
Simultaneous has ______ ROC than sequential
Why are Simultaneous Lineups Diagnostically Superior (Wixted & Mickes (2014, Psychological Review)
- proposed a diagnostic feature-detection model
-Basic idea: simultaneous lineups make it easier to appreciate the existence of shared (and therefore non-diagnostic) features
-The enhanced awareness of non-diagnostic feature makes it easier for eyewitnesses to tell the difference between innocent and guilty suspects
Diagnostic feature-detection hypothesis (Wixted & Mickes, 2014)
-Innocent and guilty suspects share facial features - namely, features that correspond to the suspect description
-The common features are largely non-diagnostic and should therefore be discounted (i.e., ignored)
-Simultaneous lineups immediately teach the eyewitness which facial features should be discounted, but sequential lineups do not
Relationship between eyewitness confidence and accuracy
-MISCONCEPTION: Research shows that even under perfect conditions, usually confidence doesn't tell you shit
-This misconception is based on the use of the wrong statistic to measure the relationship between confidence and accuracy
Correlation vs. Confidence-Accuracy Characteristic (CAC Analysis)
-Correlation turns out to be the wrong measure to use
-A better approach is to simply plot accuracy as a function of confidence
-Take low confidence and calculate % correct and high confidence and % correct and plot it
-When witnesses say they have high confidence, they are usually correct
Behrman and Davey (2001)
-Analyzed confidence ratings made by real eyewitnesses to IDs made from real lineups in Sacramento
-Witnessed had 3 response options: I'm sure, I'm not sure, I don't recognize
-"I am sure": 92% correct (11 of 12)
-"I think": 47% correct (7 of 13)
Houston Police Department Field Study (Wixted, Mickes, Dunn, Clark & Wells (2015))
showed that false filler identifications had a relationship with low confidence
The diagnosticity ratio wrongly suggested that
sequential lineups are superior to simultaneous lineups (but ROC analysis shows that the opposite is true)
point-biserial correlation coefficient wrongly suggested that
the relationship between eyewitness confidence and accuracy is weak (but calibration analyses show that the opposite is true)
Convicting the Innocent book
-Obtained court and police records for 161 DNA exoneration cases
-In 57% of those cases, the eyewitness was initially uncertain about his or her identification
-A witness who expresses low confidence is effectively saying "there is a good chance I am making an error"
North Park Sexual Assault Series
Summer of 2014 -- north park community was terrorized by unknown assailant targeting lone females walking at night
Violently attacked and sometimes sexually assaulted
SDPD Sex Crimes Unit
-Investigates felony sexaul assults invovling victims 14 yrs or older
-12 detectives and 2 sergeants
-24/7 on-call responsibility to respond to incidents
-2014 unit handled over 750 investigations
What started the case for North Park?
Case 1 and Case 3 had same DNA
What was special about case 5?
-video images are captured of the suspect
-Images were enhanced and disseminated to media and law enforcement
-Wife of an SDPD officer recognized symbol on shirt
How did they catch the North Park attacker?
-Undercover officers go to the restaurant and find the suspect working
-Placed under arrest based upon the video footage (DNA analysis no conducted)
-Suspect is 23 year old David Drake
-Interrogated by Detective Carmelin Rivera
Criminal profiler
A person who infers the personality, behavior, motivation and demographics of a suspect based on information gathered from a crime scene
modus operandi (MO)
method of operation, which is a recognized pattern of behavior in the commission of a crime
behaviors the offender has to do to fulfill an emotional need or a fantasy
Cesare Lobroso, The Criminal Man, 1876
-Studied 383 Italian prisoners and compared information on race, age, sex, physical characteristics, education and geographic region
-Suggested that criminals shared certain
physical characteristics
First Profile of a Serial Killer: Jack the Ripper
-n 1888, 5 women were attacked and killed on the streets of London
-First known case of killer profiling by Dr. -Thomas Bond, who performed autopsies on two of the victims
-Determined some personality traits of the killer from victim
Dr. Bond's Profile of 'Jack the Ripper'
-The killer had no knowledge of anatomy or medical training
-A 'harmless-looking and quiet man'
-Physically strong
-Composed and daring
-A loner with no real occupation
-Accuracy of this profile is unknown because the killer was never caught
Behavioral Analysis Unit 1
counterterrorism/threat assessment
Behavioral Analysis Unit 2
crimes against adults
Behavioral Analysis Unit 3
crimes against children
Behavioral Analysis Unit 4
Violent Criminal Apprehension Program-ViCAP
"Father of profiling"
-John Douglas
-25 years with the FBI
-Interviewed many serial killers/rapists
-Developed profiling techniques now taught in the FBI's Behavioral Science Unit
-Consulted on Atlanta child murders, Green River killer, Unabomber
-Wrote a book called "Mindhunter: Inside the FBI's Elite Serial Crime Unit"
Typological offender profiling
-Developed by the FBI in the 1970s and 1980s
-There are different types of offender
-Behavioral evidence can indicate which type of offender committed a crime
-Knowing an offender's type allows us to predict future behavior
Definition of a serial killer
"Three or more separate events in three or more separate locations with an emotional cooling off period in between homicides."
"Serial killer" term coined by
-Robert Ressler in 1970's
-Used first in the Ted Bundy case
women accounted for ____ percent of the 1,398 known victims of serial killers during the 1985 to 2010 timeframe
Females represent how much percent of homicide victims?
Serial killers are ____ men
Female Serial Murderers (Farrell et al. (2013)
-Women thought to be more reactive, rather than predatory, in their decision to murder
-Predominantly white
-Average age of 32 (range from 16-65)
-Women tend to kill quietly
-Women tend to kill individuals close to or dependent on them
Weapon of choice for women
Poison, 74% of homicides
hear voices or have visions that direct them to kill
believe that they are meant to eliminate a particular group
-Kills for pleasure, although what aspect they enjoy varies
-Gain (financial)
-Feeling of power
Herbert Mullin -- Visionary Example
-Mullin's best friend was killed in a car accident, which appears to be the breaking point in Mullin's life
-At age 17, he began to hear voices, a typical symptom of paranoid schizophrenia
-He murdered 13 people in 1972 and 1973
-Mullin was convinced that the voices in his head were the work of Satan and were directing him to "save the world"
James Vaughn -- Missionary Example
-He was a racist who joined both the Nazi party and the KKK
-Believing that becoming involved with people of another color was a sin, he felt responsible for murdering them
-He murdered numerous racially mixed couples from 1977-1980
Jeffrey Dahmer -- Hedonist Example
-He tortured and killed animals in his youth and was a loner and an outcast in high school
-As an adult, he enjoyed drugging and murdering young men and then having sex with them (necrophilia)
-He is known to have killed 17 young men between 1978 and 1991
Organized Crime Scene:
-Body is hidden
-Weapon is removed from scene
-Appears to be well-planned
-The victim is specifically targeted
-Restraints often used
-Aggression takes place before death
Disorganized Crime Scene
-Body not hidden
-Weapon is present
-Appears to be spontaneous
-Victim may be an acquaintance
-Aggression or sex post-mortem
Organized crime scene suggests an offender:
-Average or above average IQ
-Employed, usually quite skilled
-Socially competent
-Uses alcohol in commission of crime
-Uses car to drive to crime scene/hunt for victim
-Obsessed with media coverage of his crimes
Disorganized crime scene suggests an offender:
-Below average IQ
-Unstable employment record, unskilled
-Socially isolated
-Lives close to crime scene
-Strict discipline as a child
-Extremely anxious
Profiling a Serial Killer (and getting it right)
-Rochester, NY—1989, multiple murders
-Police ask for FBI profiler, Gregg McCrary
-McCrary studied the murder's MO
-Concluded that the murderer probably would return to scene of the crime
-Police delayed collecting the next victim
-Arthur Shawcross returned to the crime scene and was arrested for the murder of 11 women
Profiling a Bomber (and getting it wrong)
1996 Summer Olympics
-discovered a backpack filled with three pipe bombs on the park grounds
Richard Jewell alerted police and helped to evacuate the area before the bomb exploded
-The FBI instructed the police to search for a single, white, middle-class male with an intense interest in police work
-Jewell quickly became a suspect (because he fit the profile) and was essentially assumed guilty by sensational media coverage
-On April 13, 2005, Jewell was exonerated completely when Eric Rudolph pled guilty to carrying out the bombing attack
Two Different Approaches to profiling
1. Criminal profiling tries to identify a broad array of characteristics that are unique to the unsub (the "art" of profiling):
-Has no medical training
-A loner
-White, average intelligence

2. Case linkage analysis is more statistically oriented (the "science" of profiling):
-Behavioral consistency
-Behavioral distinctiveness
Offender Consistency Hypothesis
-Offenders display a degree of consistency in the way they commit their crimes across a series (MO, basically)
-e.g., a sexual offender will show signs of the same underlying fantasy each time he commits a crime
Offender Distinctiveness Hypothesis
-Offenders show a degree of distinctiveness in the way they commit their offenses (allowing their offenses to be distinguished from those of other offenders)
-e.g., a sexual offender's apparent fantasy will differ from that of other offenders
A Test of Consistency (Knight et al. (1998)
Assessed the consistency of behavior across the 5 most recent crimes committed by serial sex offenders using a rating scale
High consistency
-having a firearm present
-cutting/slashing clothing
-excessive response to victim resistance
-Victim being bound
Moderate consistency
-Alcohol/drug consumption during crime
-Intentional infliction of pain
excessive profanity
-Offender showing interest in the victim's enjoyment
linked cases were ____ consistent and could be differentiated from unlinked cases
an investigative strategy that uses the locations of a series of crimes to determine the most probable area of the offenders residence
Psychological Autopsies
-Involves attempts to dissect and examine psychological state of individual prior to death (e.g., before an apparent suicide)
- Based on several sources of information (interviews with family, psych records)
Death classification
natural, accidental, suicide, homicide
National Academy of Sciences
-non-profit society of distinguished scholars that was established by an Act of Congress
-Charged with providing independent, objective advice to the nation on matters related to science and technology
Dr Henry Faulds
published the first paper on the subject of fingerprints in the journal Nature. Returning to the UK in 1886, he offered the concept to the Metropolitan Police in London but it was dismissed
Sir William James Herschel
a British civil servant based in India, wrote to Nature saying that he had been using fingerprints for identification purposes
Sir Francis Galton
published a detailed statistical model of fingerprint analysis and identification and encouraged its use in forensic science in his book Finger Prints
Juan Vucetich
-an Argentine police officer who had been studying Galton pattern types for a year, made the first criminal fingerprint identification.
-He successfully proved Francisca Rojas guilty of murder after showing that the bloody fingerprint found at the crime scene was hers, and could only be hers
The Case of Francisca Rojas
-In 1892, two boys were brutally murdered
-suspicion fell on a man named Velasquez, a suitor of the children's mother. but even after torture he wouldn't confess
-Investigators found a bloody fingerprint at the crime scene
-compared the fingerprints of Rojas and Velasquez with the bloody fingerprint.
-fingerprint matched one of mother
Crime Scene Technicians
-Locate Prints
-This technician is using powder to develop latent prints
Tangen, Thompson & McCarthy (2011)
-Presented 37 qualified fingerprint experts and 37 novices with pairs of prints displayed side by side on a computer screen
-Task was to say "match" or "no match" and confidence level
-Results: "We have shown that qualified, court-practicing fingerprint experts are exceedingly accurate compared with novices, but are not infallible"
Fingerprint Experts showed a conservative response bias
tending to err on the side of caution by making more errors of the sort that could allow a guilty person to escape detection than errors of the sort that could falsely incriminate an innocent person
The FBI's Integrated Automated Fingerprint Identification System
-Latent prints can be searched against a file of 70 million prints
-The system produces a list of possible matches (n = 10 or 20)
-Checked by a qualified fingerprint examiner
Brandon Mayfield and Madrid bombing
-ran the print collected in Madrid and reported a match against one of 20 fingerprint candidates
-Brandon Mayfield, an American lawyer, was identified as a participant in the Madrid bombing based on a fingerprint match
-The FBI initially called the match "100 percent positive" and an "absolutely incontrovertible match"
-The Spanish National Police examiners concluded the prints did not match Mayfield, and after two weeks identified another man who matched
The crucial difference between:
-comparing latent fingerprints (lifted from a crime scene) to the fingerprints of a suspect
-comparing latent fingerprints to the fingerprints contained in a large database
The probability of a false alarm is
-LOW when the comparison involves a suspect
-HIGH when the comparison is made through a database search (because someone, somewhere, has fingerprints a lot like yours)
Why is the Probability of a False Alarm Higher in a Database Search?
-The "base rate" problem
Searching Face Databases
-In eyewitness identification, the police first find a suspect and then place that person in a lineup.
-Sometimes, a suspect is found by searching through many faces, which means many innocent faces are examined to find a suspect.
Forensic Odontology
-Teeth and Bite Mark Analysis
-Most forensic odontologists are practicing dentists
-However, they have gone through specialized training to understand how to apply forensic science to dentistry
-Most are members of a professional organization
Two Aspects of Forensic Odontology
1. Individual Identification
2. Bite mark analysis
Individual Identification
-Identify victims of a natural disaster by matching dental records to teeth
-Scientifically solid
Bite mark analysis
-Match a bite mark on a victim to the dentition of a defendant
-Scientific validity is currently under scrutiny
Early History of Identification using Teeth
-in 1849 the incinerated remains of George Parkman were identified using a partial denture
-identification of victims of the Vienna Opera House fire in 1881 (
Assumptions Underlying Bite-Mark Analysis
-Human dentition is unique (like DNA)
-Human skin is capable of registering bite marks in a way that makes them identifiable and distinguishable
Bitemark Evidence
The scientific basis of bite-mark analysis is under scrutiny like never before and is considered by most scientists to be invalid
False Alarm Bite Mark Analysis
-Decision = "match", truth = No Match
-Bite-mark analysts put multiple individuals in jail because of a high-confidence "match" claim
-Some of those were sent to death row
Hit Rate Bite Mark Analysis
-Decision = "match", truth = Match
-Ted Bundy brutally killed up to 40 woman
-He was convicted, sent to death row, and eventually executed because a bite-mark analyst made a high-confidence "match" claim
Blood Spatter Analysis
-Physics of flight, trigonometry used to determine origin point of blood
-Size and orientation of spatters can determine method by which stains are created
Fiber analysis
-Fibers have distinct color, diameter, shape, and chemical composition
-Microscopic and chemical analysis to compare
Arson Detection
-Search for chemical signs of accelerants (gasoline, etc.)
-Test burn scenarios
-Direct comparison of known samples and unknowns from crime
-Striations or firing pin impressions
Forensic DNA Analysis is not Error-Free
-contamination can occur in the testing lab or at the crime scene
-Very small amounts of DNA are becoming detectable, so the slightest contamination can now falsely incriminate someone
The Murder of Jane Mixer
-a 23-year-old University of Michigan law student who was found dead in the early morning
-arranged to meet a stranger the night before, who was supposed to drive her home to Muskegon, Michigan
-initially thought to be a victim of a serial killer who was operating in the area
-In 2002, 33 years after the crime, a "cold case" analysis of DNA from the Mixer crime scene evidence was conducted
-they matched the known profiles of two men.
John Ruelas
-He murdered his mother in early 2002
-He was arrested for that crime, and his DNA profile was entered into the database
-The unknown DNA profile from a drop of blood taken from Mixer's left hand in 1969 matched his known profile
Gary Leiterman
-Leiterman forged a prescription in 2001 after he had become addicted to pain medication following a bout of kidney stones
-He was arrested for that crime, and his DNA profile was entered into the database
-The unknown DNA profile from a stain on the pantyhose Mixer was wearing in 1969 matched his known profile
Did Leiterman and Ruelas commit the murder together?
-Ruelas was a 4-year-old preschooler in 1969 and was therefore ruled out as a suspect
-Why his DNA showed up in the analysis was not explained and remains completely mysterious to this day
-Therefore, only Leiterman was convicted of Mixer's murder
-But what explains the Ruelas DNA evidence?
Theory #1 (the prosecution's theory) of Mixer's murder
-Leiterman killed Jane Mixer and left his DNA at the crime scene in 1969
-4-year-old John Ruelas was there, too, bleeding on Mixer for unknown reasons
-The "co-ed" serial killer, John Norman Collins , who was murdering women at the same time and in the same area, was assumed to be innocent of this particular crime
Theory #2 (the defense's theory) of Mixer's murder
-The DNA samples of all 3 people were analyzed in the same lab at nearly the same time
-The Mixer evidence was contaminated with DNA from both Ruelas and Leiterman
-The obvious suspect (i.e., the serial killer) committed the murder
The sum total of evidence against Leiterman
-The cold-case DNA match, which occurred under disconcerting circumstances
-Leiterman owned a .22 caliber pistol in 1969, and Mixer was shot with a .22.
-On a phone book found in the student union building where Mixer had arranged a ride home, someone had jotted down the words "Mixer" and "Muskegeon." The prosecution's handwriting expert conclusively determined that Leiterman wrote those words.
John Norman Collins
- operating serial killer at the time of Mixer's murder
-He was tried and convicted only for the murder of Karen Sue Beineman but is strongly suspected of murdering many of the others on this list
Did John Norman Collins also murder Jane Mixer?
-Mixer was murdered in the middle of this killing spree (March, 1969), but at that time, only she had been shot in the head with a .22, raising doubts that Collins was the killer
-But Alice Kalom was also shot in the head with a .22
Alice Kalom
-Kalom was killed 10 weeks after Mixer
-The murder weapon was a .22 caliber gun, just as in the case of Jane Mixer.
-Both Kalom and Mixer were University of Michigan graduate students
Convincing evidence links Collins to the murder of Kalom
-Collins was seen very near Kalom's last known location on the day she disappeared
-Roommate Arnie Davis told police that Collins brought Kalom back to their apartment in Ypsilanti that day
-Collins was known to have recently stolen a .22 caliber pistol
-Blood found in a car registered to Collins's mother matched Kalom's blood on 5 independent factors
What was Collins doing on the night of Mixer's murder (March 20, 1969)?
-Notes made by Officer Larry Mathewson indicate that Collins did not show up for work the night of March 20, 1969
-Collins normally worked the 11pm-to-3am shift
-The murder of Jane Mixer was estimated to have occurred between midnight and 3 am of March 21, 1969
David Johnson
- a note found in Jane Mixer's apartment indicated that she expected someone named "David Johnson" to show up at 6:30 pm to give her a ride to Muskegon
-No connection between the name "David Johnson" and Gary Leiterman was ever established.
-Serial killer John Norman Collins was intimately acquainted with someone named David Johnson at Eastern Michigan University
Does the MO in Mixer's murder exonerate Collins?
- there were differences in Mixer's murders compared with Collin's MO
- Mixer was not beaten, stabbed or mutilated
-Mixer was not sexually assaulted
Similarities between Mixer's murder and the other 6 murders:
-Mixer was killed in the middle of a serial killer's murder spree, and her body was found in the vicinity of the other bodies
-Mixer was shot with a .22
-she was picked up for a ride near a university union building
- she had been killed elsewhere and her body dumped, and some of her clothes were neatly stacked around her
-a ligature was tied tightly around her neck