CHAPTER 1 - INTRODUCTION TO FORENSIC PSYCHOLOGY

What is Forensic Psychology?

• Research related to human behaviour and legal processes

• Practice of psychology in legal system

• Clinical practice in the legal system (assessments/treatments)

Types of Forensic Psychologists

• clinician

• researcher

• legal scholar

Clinician

• jobs may include research or practice

• area of interest is mental health and the law

• training includes M.A. or Ph.D. in

  psychology + internships

Researcher

• jobs may include research

• area of interest is human behaviour and the law

• need graduate training in psychology + research on forensic topic

Legal Scholar

• jobs may include research/analysis

• area of interest is laws, legal movements, and policy as they pertain to mental health/human behaviour

• must have a PhD in psychology + L.L.B. in law

• takes about 13 years of schooling

Psychology AND the law:

Use of psychology to study the operation of the legal system

Psychology IN the law:

Use of psychology within the legal system as it currently operates

Psychology OF the law:

Use of psychology to study the law itself

DANIEL MCNAUGHTEN

• Attempted assassination of British

  Prime Minister Robert Peel

• Found not guilty by reason of insanity

• Established McNaughten rule

JAMES CATTELL

• First to conduct eyewitness testimony research

• Questions about everyday observations

• Low accuracy, high confidence

• Believed findings would help the courts

ALFRED BINET

Suggestibility in children:

• Showed children objects, asked probing & leading questions

• Children susceptible to leading questions

• Asking open-ended questions = most accurate responses

WILLIAM STERN

The eyewitness “reality experiment”

Staged event:

• Students fighting, one student pulls a gun

• Interviewed about witnessed event

• Negative impact of emotional arousal on accuracy

ALBERT VON SCHRENCK-NOTZING

• Gave testimony in murder trial

• Extensive pre-trial press coverage

• Testified about retroactive memory falsification:

  • Confusion about what is witnessed vs. what is heard or seen later

JULIAN VARENDONCK

• Expert witness in murder trial of young girl

• Victim’s friends suggestively interviewed

  • Changed original testimony

  • Provided details about perpetrator

• Research demonstrated inaccurate recall in children

HUGO MUNSTERBERG

• Conducted case analysis for lawyers

• Resistance from legal scholars and the press

• On the Witness Stand (1908) discussed psychology and the legal system

  • Pushed psychology into legal arena

• Father of forensic psychology

WILLIAM MARSTON

• First professor of legal psychology

• Research on lie detection

  • Invented a version of polygraph

• Research on jury system

STATE V. DRIVER

• First use of expert testimony in US

• Attempted sexual assault of young girl

• Psychological test data – victim was vulnerable and could not be believed

• Testimony rejected

• Ruled that psychological tests can’t yet detect lies

• Partial victory for forensic psychology

BROWN V. BOARD OF ED.

• Psychologists submitted a court brief outlining the detrimental effects of segregation

• US Supreme Court acknowledged social science research for the first time

JENKINS V. U.S.

• Clinical psychologists argued that defendant was not guilty due to insanity (schizophrenia)

• Judge instructed jury to ignore the psychologists

• “Not qualified to provide expert testimony on the issue of mental disease”

• Ruling appealed – conviction reversed

Why is Forensic Psychology considered a distinct discipline?

• Textbooks

• Academic journals

• Professional associations (e.g., AP-LS)

• Training opportunities

• Formally recognized as specialty by APA

Trial Consultant

• Hired by lawyer/legal client

• Many tasks to help in preparing for and carrying out a trial

• Various ethical responsibilities

  • E.g., asked to help improve witness credibility when the witness is lying

Expert Witness

• Provide testimony during a trial

• Aid in understanding a topic

• Provide an opinion

Psychology V. Law

	PSYCHOLOGY	LAW
EPISTEMOLOGY	Experiments	Adversarial
NATURE OF LAW	Descriptive	Prescriptive
KNOWLEDGE	Research	Stare desisis/legal precedent
METHODOLOGY	Nomothetic	Idiographic
CRITERION	Strict	Lenient
PRINCIPLES	Multiple	Single
LATITUDE IN COURT	Limited	Unlimited

GENERAL ACCEPTANCE TEST (1923)

• Frye v. U.S.

• Polygraph expert witness rejected

• Scientific evidence must have gained general acceptance in the field in which it belongs

US: DAUBERT CRITERIA (1993)

1. Peer reviewed

2. Testable

3. Recognized rate of error

4. Meet professional standards

CANADA: MOHAN CRITERIA (1994)

1. Qualified expert

2. Relevant (help establish facts)

3. Necessary to educate court (beyond common sense)

4. Absence of any exclusionary rule