PSYC - Unit 1

Introduction To Forensic Psychology

What is Forensic Psychology?

• Narrow definitions
  • Clinical practice in the legal system
  • Only those who treat and asses patience in the legal system
• Broad definitions
  • Research related to human behaviour and legal processes
  • Practice of Psychology in the legal system
• “a field of psychology that deals with all aspects of human behaviour as it relates to the law or legal system”

Types of Forensic Psychologists

• Clinician
• Researcher

• Legal Scholar
  • PhD in psychology and L.L.B. in Law
    • Analyze mental health law
    • Analyze legal movements
    • Policy analysis and legislative consultation - Law-making
    • Program at Simon Fraser University

Psychology & Law

1. Psychology and the law
   1. The use of psychology to study the operation of the legal system (e.g., eyewitness lineups)
2. Psychology in the law
   1. The use of psychology within the legal system as it currently operates (e.g., expert testimony)
3. Psychology of the law
   1. The use of psychology to study the law itself

Brief History of Forensic Psychology

• Early Research
  • McNaughten (1843) (appealing insanity)
    • The attempted assassination of British Prime Minister Robert Peel instead killed his secretary
    • Found not guilty because of insanity
    • Established McNaughten rule
  • Cattell (1895) (Eye-witness testimony with confidence)
    • Questions about everyday observations
    • Relationship between confidence and accuracy
  • Binet (1900) (Children susceptible to leading questioning)
    • Suggestibility in children
    • Impact of Leading Questions
  • Stern (1910) (reality being bent by high emotions witnesses)
    • The eyewitness reality experiment
    • Impact of emotional arousal
  • Munsterberg (1908)
    • Father of Forensic Psychology
    • On The Witness Stand
    • Pushed Psychology into the legal arena
• The Court
  • State v. Driver (1921)
    • First use of expert testimony
    • Partial victory for Forensic Psychology
  • Brown v. Board of Education (1954)
    • Psychologists submitted a court brief outlining the detrimental effects of segregation
    • U.S. Supreme Court referenced brief
  • Jenkins v. United States (1962)
    • Ruling that some psychologists are qualified to provide testimony
• When expert testimony goes wrong…
  • Dale W. Griffis
    • Expert witness in West Memphis 3 Case
    • Three teenagers were wrongfully convicted of killing three boys
  • Dr. Griffis:
    • “The date of the killings, near a pagan holiday, was significant, as well as the fact that there was a full moon."
    • “Also, the victims were all eight years old and eight is a witches' number.
• Admissibility of Expert Testimony: USA
  • For forensic psychologists to provide testimony in court, they must meet certain criteria
  • Frye v. United States (1923)
    • Frye tried for Murder
    • Polygraph exam passed
    • Results inadmissible – not generally acceptable
  • General Acceptance Test – very vague and causes confusion
    • The testimony must be generally accepted within the field
  • Daubert criteria
    • Provided by a qualified expert
    • Relevant
    • Reliable/Valid
      • Peer reviewed
      • Testable (i.e. falsifiable)
      • Recognized rate of error
      • Meet professional standards
• Admissibility of Expert Testimony: Canada
  • Mohan Criteria
    • Provided by an expert
    • Relevant
    • Necessary
    • Not violating rules of exclusion

Psychological Theories of Crime

• Psychoanalytic
  • Internal dynamics and early experiences
  • Example: Theory of Maternal Deprivation (John Bowlby)
    • Early separation from the mother prevents effective social development
    • Results in Antisocial Behaviour Patterns
• Learning
  • Learning through direct and indirect consequences
  • Example: Social Learning Theory (Albert Bandura)
    • Criminal behaviour is learned
    • Direct and indirect reinforcement (e.g., anti-social peers, violence on television)
• Personality
  • People commit crimes because of their personality traits
  • Example: Bio-social Theory (Hans Eysenck)
    • Testable
    • PEN Model
      • People high on Neuroticism and Extraversion are more likely to become involved in crime