flexible vs fixed battery daubert/frye. the scientific evidence standard the frye test –...

Flexible vs Fixed BatteryDaubert/Frye

The Scientific Evidence Standard

• The Frye Test– “general acceptance in the field”• E.g. Newton’s laws of physics vs. lunar influences on

behavior

– Frye Test 1: Fundamental Scientific Principle or Discovery

– Frye Test 2: The technique used for applying the fundamental scientific principle or discovery

– Frye Test 3: the technique’s specific application on which the expert testimony is based

The Scientific Evidence Standard

• The Daubert Procedings– The link between a drug and birth defects –

plaintiffs tried to admit a re-analysis of previous data, but because it hadn’t been peer-reviewed, it did not meet Frye standards

– Supreme Court ruled that “general acceptance” was too demanding

Frye v Daubert

Frye• The basic Fry rule:

– Testimony must be based on a principle that is “sufficiently established to have gained general acceptance”

• What does the test involve?– 1. A pre-trial ruling– 2. whether the basic principle

is ultimately based has been– 3. generally accepted

Daubert• Basic Daubert rule:

– Reasoning or methodology underlying the testimony must be scientifically valid

• What does the test involve?– 1. a preliminary ruling– 2. on whether the theory or

technique – 3. is scientifically valid

Factors for scientific validity

• 1. widespread acceptance• 2. peer review• 3. publication• 4. testing• 5. rates of error• 6. the existence of standards

Where does Florida stand?

• Adopted Frye in 1989– Cannot admit post-hypnotic testimony– Stokes v State: “a courtroom is not a laboratory,

and as such it is not the place to conduct scientific experiments. If the scientific community considers a procedure or process unreliable for its own purposes, then the procedure must be considered less reliable for courtroom use.”

The Trial Court as GatekeeperKeeping out “junk science” one trial at a time

• 1. a two part test governs expert testimony: – Expert must be qualified– Testimony must be relevant and based on a reliable

foundation• 2. the expert must truly have expertise concerning

subject matter. Can’t draw from unreliable foundational data.

• 3. must not used flawed methodology• 4. “scientific evidence which is not grounded in the

methods and procedures of science is no more than subjective belief or unsupported speculation”

Daubert/Frye/Flexible/Fixed

• Where do NP batteries fall on the Daubert – Frye spectrum?

• Case study: – Charles Sebastianelli – work incident in which milk

crate fell on his head – went to ED on 3/7/1997– 3/17/1997 – solicited murder of business partner,

wife, and son – charted with solicitation of murder– Referred to NP because complained that he had

“not been thinking right”

Sebastianelli Case

Attention/Concentration: abnormalLanguage: mild impairment in comprehension, significant impairment in expressive languageVerbal memory: abnormalVisual memory: abnormalAbstraction/conceptualization: abnormal

Case for it not being admitted:

– 1. no control for faking– 2. no known accuracy rates– 3. ignored statistical checks– 4. did not proper norms (e.g. not age-corrected)– 5. ignored literature in interpretation

At trial

• What the prosecutor said: – 1. No used any accurate method of ruling out faking

despite several methods available (used a personality test instead)

– 2. When properly scored, test battery became completely normal

– 3. Problem of ecological validity: transcript of taped solicitation didn’t show signs of poor concentration, wording finding, fluency, or grammar problems. Could discuss personal history and recent events. No signs of impulsivity.

Results of the Trial

• Guilty of solicitation on only one count – related to business partner (not guilty for wife and son)

• Post trial interviews: “said they wanted to let him go all together (he was, after all, just an old man and he hadn’t actually hurt anyone) but there was simply too much evidence against him.

• Sentenced to 6 years in state prison

What McKinzey and Zieglar believe can be gleaned from this

“Psychologists will rarely have any conventional testimony excluded. It looks as if psychologists can say anything: judges will continue to let it in, allowing psychological information to be considered according to the weight of the evidence, if only to avoid chancing be overturned on appeal... The judge did not exclude evidence. She merely considered which of two experts she believed more. The more cynical of us would wonder how an expert with Dr. Reitan’s credentials could NOT be the favored one.”

Bigler Rebuttal(For Flexible Batteries)

• Exclusive use of fixed battery is “passe” • HRB was developed before many diagnostic

tools were developed, so the comparison of “brain damaged” patients from the 1950s to those of today, and their use as the gold standard is suspect

Bigler Rebuttal(For Flexible Batteries)

• Subjective symptoms should not be ruled out because may be first signs of objective neurological deficit

• Few studies in neuropsychological literature meet standards for “proper base rates” of symptoms

• Flexible batteries reflect modern approaches to NP practice, allowing for use of neurodiagnostic, clinical neuroscience, and/or cognitive neuroscience advancements

Discussion Questions

• Would you use a fixed or flexible battery? • How do you think it reflects Daubert criteria

and Frye criteria? • What tests do you consider important for

common forensic cases (e.g. head injury)?