Upgrade to remove ads
CRJU 367 Exam 2
Terms in this set (79)
Forensic Identification Evidence
Trying to match things
- Firearm: how does the gun mark up the bullet?
- Fingerprint: riders, swirls, etc.
- DNA: The golden standard
- Others: bike tracks, shoe prints, voice, etc.
When samples of trace evidence match samples taken from a suspect or from a tool used by the suspect, indicating that the two samples came from a common source
Four Types of Source Attribution
1. Qualitative Match: lowest standard. "Strong or weak" but no standard set for these terms.
2. Simple Match: "It was consistent with"
3. Match with statistics: Probabilistic evidence. How many other people in the population could this match? (Ex black hair vs red hair)
- Helps indicate strength
4. Individualization: Highest standard. Sample matches and all others are excluded.
- Mainly DNA and fingerprinting
Features common to a group. Blood type, hair color, etc.
Can only belong to one person. DNA, Fingerprints, etc.
A measure is consistently produced
Inter-rater reliability: Two people getting a similar outcome on a test
Test retest reliability: One person takes test multiple ties and gets same results.
The extent to which a test measures or predicts what it is supposed to. Accuracy
Highest to Lowest reliability of forensic evidence types
1. DNA: "The golden standard"
3. Bullet matching
4. Tool signature patterns: not everyone signs the same way every time
5. Bite mark analysis
6. Handwriting analysis
- The golden standard of forensic evidence
- Goal: to determine identity of an unknown sample
- Method: compare DNA between samples (found at scene to that of suspect)
DNA Sample Types
- Single Source sample: uses objective methods to match DNA. Determines if alleles match between 2 samples
-Mixture sample: 2 types mixed together. Can remove victim DNA and test what remains.
- Complex mixture sample: Has multiple offenders, hard to sort out
- Low copy number sample: there is not much DNA available to test. Trace or touch DNA
** Most likely to involve a subject interpretation from a forensic examiner
Issues with low quality samples
Valid method, but requires more interpretation
- Evaluators are forced to make decisions with low copy number samples and complex mixture samples
Random Match Probability
Assesses whether or not the match between the DNA profile obtained from the evidence and the DNA profile obtained from the suspect occurs by chance (coincidence).
- Usually high numbers/very rare (One in a billion)
- Indicates probability of a match (NOT guilt of suspect!)
False Match Probability
Accounts for error in testing due to cross contamination, mislabeling, misinterpretation, planting of evidence, etc.
- Started in 2009, so not often reported. People still lowering on developing statistics
Jurors: RMP and FMP
- Both affect probative value of evidence
- Jurors have trouble using these to determine probative value
- Study: By increasing RMP by a factor of 10, jurors increase what they think of guilt by 2-3x and ignore FMP
Computer program into which DNA samples are imported.
- Runs algorithms to determine the likelihood of a match (Cold hits)
- Benefits: removes human element, no conformation bias, ability to analyze more complex mixtures and smaller amounts of DNA
- Downfalls: Source code is not available (can't be cross contemned), Running same sample will often produce different outcomes
Data base trawls
The new "DNA War"
- Value of hits questioned: the more you go through, the more likely you are to find someone with a similar profile
- On the other hand, the more you exclude people the more you can confirm the offender is in fact guilty
- Raises privacy concerns: not everyone in database is a criminal
Scurich and John's Study
Manipulated how match was obtained (conventional vs trawls) and if other evidence in case was strong (had no alibi, similar characteristics) or weak (partial alibi cooperated by mother and no witnesses)
- Non effect on how guilty they think a person is, but less likely to convict with trawl than with conventional methods
- Shows that people are skeptical about the probative value!
Issue of conformation bias and expectancy effects in forensic analysis
- DNA is usually viewed as being very objective, when in fact this is not always the case with more complex samples
Dror- evidence from case involving gang rape
- Gives evidence to 17 analysts and only one says the sample cannot be excluded (what happened in original case)
- 12 said can exclude, remaining said inconclusive
Shows DNA can be influenced by contextual information and make it more subjective
The weight assigned to a piece of evidence by a juror
Thompson's Bad apples
- CJS is a set of loosely coupled subsystems. Everyone works autonomously, creating checks and balances (low quality evidence not presumed to wrongfully convict)
- When a mistake is made, its due to a malicious, incompetent, or careless employee
- Solution: get rid of these bad apples!
These assumptions ignore the larger organizational issues
- System is actually tightly coupled (workplace culture)
- Josiah Sutton case in which attorney did not want to criticize DNA in fear of not being given good cases in the future (Texas)
Can result in system failures
- Prosecutors are not as concerned with accuracy as they are with getting a win
- Defense attorneys not pointing out in ear of not getting good cases
In all criminal prosecutions, the accused should enjoy the right to a speedy and public trial , by an impartial jury of the state and district where in the crime has been committed.
- What IS an impartial jury?
Jury selection and service act
Juries must be a fair cross section of the community
-Voter registration is the primary source for finding jurors
- Underrepresentation of people of low SES, some racial minorities, people who move often, people who have recently turned 18 and did not yet register
Venire is selected from a jury pool sample
Gets significantly smaller: no shows, undue hardships (sole earners, medical conditions, student)
Venire "Come when called" Latin
Void Dire "To speak the truth" French
Challenge in a cause: a juror is unlikely to be partial.
- Ex: Retired law enforcement officer and case is about police brutality
- Infinite number
Preemptory challenge: Do not need to give a reason for dismissal
-Finite number depending on type of case- criminal cases have more than civil cases
Batson v. Kentucky (1986)
African American male was convicted on criminal burglary charges with all 4 blacks being removed from the jury pool
Case was appealed and moved to appellate court: challenge case on basis of procedural ground
Supreme Court ruled that his constitutional rights were violated due to the 6th amendment (No impartial jury)
You cannot purposely exclude venire members based on race- prosecutors must articulate an actual reason
Norton and Sommers
Participants asked to read a summary of case and juror profiles- asked to eliminate one of two potential jurors (Whichever was more biased)
1st: Journalist who often wrote about police misconduct but tried to remain as objective as possible
2nd: Someone who was skeptical of statistics
Manipulated race- people excluded the black juror more often whether he was presented as one or two
Participants offered race neutral reasoning for their responses
Participant pool or law students and attorneys
"A nearly un-hurdalable bar"
Racial disparities in preemptory challenges are still fairly common
Extremely rare to be able to prove that the Batson rule was violated
Prosecutors are trained on how to avoid the Batson rule
Should we change the preemptory rule?
Pre-trial publicity bias
Influences the presumption of guilt
Martin Shkreli: an investigator and hedge fund manager charged with 8 counts of securities and wire fraud
- Also responsible for raising the price of a prescription by 5,000% (Not part of trial)
- More than 200 venire members excluded
In some cases can be moved to area in which case is less publicized, but hard to do so when defendant is known on a national level
Jurors try to fit the evidence they hear at trial into a coherent story, and ultimately reach a verdict that best fits the story they have created
- How most jurors behave
Jurors assign some type of statistic probability to each piece of evidence.
- Focuses on the probative value, computational
- Jurors often don't factor in false match probability
A phenomenon that occurs when another person's behavior provides information about what is appropriate
- Giving into group pressure
Conformity occurring when people accept evidence about reality provided by other people.
- Other jurors making complexing arguments
Evidence-driven deliberation style
A jury deliberation style where the jurors decide to delay the vote until after considerable discussion focusing on evaluations of the evidence in the case
- Careful and systematic
- Tends to be more beneficial
- Allows for a more objective discussion: evaluating in a way that is trying to find the "holes"
Verdict-driven deliberation style
During the deliberation process, jury votes shortly after they begin and conduct subsequent discussions around the verdict votes.
- Tends to encourage jurors to sort the evidence into categories (suppurating conviction or supporting acquittal)
- Drawback: once positions are known, each side is just trying to convince the other
Size of Jury
Larger juries deliberate longer, recall evidence more accurately, generate more arguments, agree more on their ratings of jury performance, are more representative of the community, and produce more consistent verdicts
- Help pick what jurors might be most favorable to case
- Witness preparation
- Mock trials
- Prepare experts to frame evidence in a powerful and compelling way that will make sense to jurors
Ethical concerns with trial consultants
This is something lawyers already do... just another strategy that can be used
Unfair to people that cannot afford?
When does jury outcome matter most?
When case is somewhere in the middle
Do juror characteristics predict verdicts?
No! But the following may influence
- Locus of control : internal vs external (internal may be more punitive)
- Belief in a just world: sometimes and outcome (severe punishment) is a necessary thing
- Authoritarianism: support for authority and respect for tradition
- There are only modest associations between traits and conviction proneness
- Juror defendant similarity- mixed results
1800's Child Saving Movement
Focused on rehabilitation for juveniles
Very informal- kids often taken in by families
1900's Formal Juvenile justice system created
Certain offenses are matched with certain consequences- more predictable
Power of the state to act on behalf of the child and provide care and protection equivalent to that of a parent
The government is regarded as the legal protector of citizens unable to protect themselves
Violations of the law that pertain to minors but not adults
- Viewed more as delinquency than as a crime
- Kids need extra protections and attention to make sure they are not going down a path of crime
Violent or property crimes that can occur at any age
Types of interventions
Fines: least restrictive measure possible, but most kids are not financially independent
Community service: holds offender accountable
Group Homes: Provides more structure for rehabilitation
State prisons: typically for criminal offenders
Evidence of poor decision making for teens
Get in more car accidents, try drugs, fight, unprotected sex, and crime
The age crime curve
- Starts increasing around 14-15
- Peaks at 19
- Females have a lower overall rate but a similar peak pattern
Psycho Social maturity
A composite score made up of components
- Impulse control
- Resistance to peer influence
- Future orientation (Marshmallow study)
- Less sensation seeking
- Ability to correctly receive risks: as you gain more psycho social maturity you more appropriately with risks and benefits
Does not fully mature until the age of 25
Hodgson v. Minnesota (1990)
Overturned two parent notification requirement for a minor abortions, but upheld one parent notifications and 48 hour waiting period
Roper v. Simmons (2005)
Execution of offenders for crimes committed while under the age of 18 is unconstitutional
17 Year old sentenced to death for murder and burglary- claimed it was cruel and unusual punishment
Graham v. Florida (2010)
Juveniles cannot be sentenced to life without parole for non-homicide offenses
Miller v. Alabama (2012)
Mandatory sentences of life without the possibility of parole are unconstitutional for juvenile offenders (for any crime)
Montgomery v. Louisiana (2016)
Applied Miller retroactively
Cognitive Maturity: Intellectual functioning to be able to reason through a big decision. You have time to make the decision, and can get adults opinions
Psychosocial Maturity: Crimes are committed with peers and are often a "snap decision"
Why do we punish people for criminal offenses?
Deterrence, Rehabilitation, Culpability
Insanity (Legal term, not psychological)
Different Jurisdictions have different definitions
- Always involved assessing ones mental state at the time of the crime
- ID is codified in every state except Montana, Idaho, Utah, and Kansas
There are historical trends in which definitions tend to be most widely used
Daniel M'Naghten (1843)
- Believed in a conspiracy: the government was out to get him
- Attempted to kill Robert Peel, the prime minister of England
- 9 Medical experts testified he was insane
-Found NGRI: not guilty by reason of insanity (Queen Victoria and public outraged)
A rule for determining insanity, which asks whether the defendant knew what he or she was doing or whether the defendant knew that what he or she was doing was wrong.
Criticisms: Cognition is only one aspect of insanity
- it doesn't take into account whether or not the person could control their actions
Irresistible Impulse Test
A test that provides that the defendant is not guilty due to insanity if, at the time of the crime, the defendant could not control his or her actions, even if they knew them to be wrong
AKA the policeman at the elbow test
Criticisms: Difficult to prove
Monte Durham (1954)
- Arrested for breaking and entering, trial court refused to let him plead guilty
- US Court of appeals in DC took up case
An accused is not criminally responsible if his unlawful act was the product of mental disease or defect
- Only used in New Hampshire
- Also known as the product test
ALI Model Penal Code
American law institute publishes their own standard (1960's)
- "A person is not responsible for criminal conduct if at the time of such conduct, as a result ofmental disease or defect, he lacks substantial capacity either to appreciate the criminality [wrongfulness] of his conduct or to conform his conduct to the requirements of the law"
Phineas Gage 1848
Railroad worker who survived a severe brain injury that dramatically changed his personality and behavior; case played a role in the development of the understanding of the localization of brain function
Charles Whitman (1966)
- Shot people at the University of Texas from clock tower, murdered mom and wife
- Left a note asking for an autopsy to be done
- He had a brain tumor pushing on his amygdala
"Alex" case 2000
- Started having sex with hookers and watching child porn around age of 40
- Molested his own child and his wife found out
- Is found to have a tumor. Upon its removal urges stop
- Starts having urges again due to tumor regrowth
- New England Patriot convicted of multiple murders
- Memory loss, impulsivity, and aggression can all be attributed to CTE (brain disease common in athletes)
- CTE was not brought up at his trial
- There are a number of explanations for crime (rational choice theory, poverty) mostly focused on social factors
- This technique looks at the brain as the cause
- Neuroimaging: measures blood in the brain and abnormalities
- Explains some crime and misbehavior, but have limited explanations (all correlational)
Interpreting brain scans
- What is the cut off for culpability?
-Descriptive: cant make causal link
"The anatomy of violence"
- Book by professor at Upenn
- Combining social factors with brain imagineer to predict people who will commit crimes in future
- Biological, social, and physical
Neuroscience as evidence
- Becoming more and more prominent
- Common uses: mitigation, competency, mental state
- "My brain made me do it": new evidence for an old argument
- Experts introduce neuropsychological assessments and brain scans
Defense vs Prosecutor
- bolster preexisting legal defenses
- mitigate defendants culpability and punishment
- No rehabilitating defendants
- Future likely dangerous
Questions of culpability
- Specific aggravating and mitigating circumstances
Concerns about Neuroimages in courtrooms
- Visual persuasiveness: depictions of evidence are more appealing (impact of gory photos)
- Neuroscience as legitimacy: using legitimacy of field to support credibility of claims
- CSI effect: crime dramas have increased confidence in scientific evidence
Green and Cahill: purpose of study
To assess impact of neuroscience evidence on mock jurors sentencing recommendations and impressions of a capital defendant
State of empirical research and current unanswered questions
- Hold a big impact with juries but only two scientific pieces done to back it up
1. Gurley and Marcus: Neuropsychological evidence, including results from an MRI and testimony from a neuropsychologist cease the chance that a defendant will be ruled not guilty by reason of insanity
2. Schweitzer and Saks: the effect of neuroscientific evidence may be due to expert testimony more so than neuroscience images
- They do not consider how perceptions may change based on future dangerousness of defendant
- 2 (low danger, high danger) x 3 (diagnostic only, neuropsychological, or neuroimaging)
between subjects design
- All given facts of murder, likelihood of dangerousness in future, and evidence concerning psychiatric diagnosis
- Neuro-sciencetific evidence is mitigating evidence regardless of high risk or low risk
YOU MIGHT ALSO LIKE...
Forensic Psychology: Crimes and Evidence
Criminal Investigation Chapter 5 Review
PSYC401 Ch. 13
Chapter 5: Forensics/Physical Evidence
OTHER SETS BY THIS CREATOR
CRJU 303 EXAM 3
CRJU 303 Exam 2
CRJU 303 Exam 1
Cognitive Psych Exam 3