Graham DaviesLegal Psychology

Week 6

Expert Evidence on Eyewitness Testimony

The Psychologist as Eyewitness Expert

• First recorded case – 1896

- Shrenck – Notzing in Germany

• Most prevalent in the US

- 450 trials in 25 States (Brigham, 1988)

- 87% for the Defence (Kassin et al. 1989)

• Landmark Trials

- Robert Buckhout and the Angela Davies case (1972)

- Elizabeth Loftus vs. Lenore Terr in People vs. Franklin (1994)

Fluctuating Rules for Admission of Expert Testimony – thumbs down?

• The ‘Frye rule’

- testimony to be based on information and data

generally accepted in the expert’s field

• US vs. Amaral (1973)

- rejects eyewitness expert

- expert evidence must be beyond common knowledge

of the jury

- evidence must be more probative than prejudicial

Fluctuating Rules for Admission of Expert Testimony – thumbs up?

• Federal Rules of Evidence (1975)

- does it assist the Court ?

- is the testimony sufficiently reliable ?

• State of Arizona vs. Chapple (1983)

- decision reversed because no expert allowed

• The Daubert Judgement (1993)

- reliability and relevance of evidence critical

- peer review and publication relevant criteria

But the legal door still only half open

The Backlash: McCloskey & Egeth (1983)

• Goals of expert testimony- to correct any misapprehensions of jurors - to assist in distinguishing reliable from

-unreliable testimony

• Neither of these achieved- jurors not given new or reliable information- jurors are just made more sceptical without improving reliability

Psychologists should stay out of the courts !

Do jurors over-believe eyewitness testimony ?

• Experts summarise state of knowledge

- Estimator and system variables

- reliance on experimental findings

• Questionnaire Studies (Deffenbacher & Loftus, 1982)

- good grasp of cross-race ID; biased parades

- poor grasp of weapon focus; confidence and

accuracy

- calibration issue (Wells, 1986)

- Judges’ knowledge and attitudes (Wise & Safer, 2004)

• Eyewitness discrediting effect (Loftus, 1974)

- not always reliable (Sanders et al. 1983)

Are Jurors made over-sceptical toward eyewitness testimony ?

• Experts reduce conviction rate (62% to 42%)

but no improvement in accuracy

(Wells et al. 1980)

• But if experts focus on critical variables they do improve juror accuracy

(Wells & Wright, 1983)• Didactic vs. Case-based testimony

Subsequent Research

• Much more research on critical variables

- weapon focus meta-analysis (Stablay, 1992)

• More realistic field studies

- cross-racial ID (Brigham et al. 1982)

- unconscious transference (Read et al. 1990)

General Acceptance ?

• An emerging consensus (Kassin et al. 2001)

- 80% or more agreement by experts

- system variables (e.g. line-up instructions; mugshot bias)

- estimator variables (e.g. post-event information,

leading questions; cross-race ID)

• Consensus statements

- children’s suggestibility in interviewing (Ceci & Bruck, 1995)

- identification methods (Wells et al. 2001)

Eyewitness Testimony in the United Kingdom

• Testimony of psychologists in court - rarely permitted (R v. Turner, 1975) - briefing (typically) the Defence through reports

• Judge takes on ‘educational’ role - ‘Turnbull’ directions (Devlin 1976)

• Little signs of change - 1993 Royal Commission on Criminal Justice - 2002 Auld Committee Report - But psychologists appear regularly in civil cases