Admissibility:
The Expert Witness:
It begins with the sword:
When fighter schools were shut down in the middle ages, combat masters would sell their testimony to make money. Charges of perjury could be met with dual of law
And evolved into science:
The professional detective and professional scientists slightly precede their presence in literature
Eugene François Vidocq 1775-1857
Sherlock Holms 1887-1927
What is an Expert witness?
An expert witness is a person engaged to give an opinion based on experience, knowledge, and expertise. The overriding duty of an expert witness is to provide independent, impartial, and unbiased evidence to the court or tribunal
Evidence from an expert is used when the evaluation of the issues in dispute involves technical or other subject knowledge that only real experts would have and that would likely be outside the knowledge of laypersons and trying the case
Qualification of an expert is the prevue of the judge. This means that the court will be the ultimate arbitrator of whether or not a potential expert probable has the necessary knowledge to aid the trier of fact understand the relevant facts of the case
Note: Expert witness may offer opinion
The Fact Witness:
There is an important difference between opinion evidence from a layperson and an expert in regards to what is acceptable evidence. A lay witness AKA fact witness is normally restricted to factual matters that are within someone’s personal knowledge: he or she is not permitted to express opinions
Fact witnesses need to have knowledge specific to the case at hand. They can be eyewitnesses or other involved people
Data from the innocence project suggests that almost ¾ of the wrongful convictions were based on bad eyewitness identifications
Numerous experiments have shown that eyewitnesses are not reliable, not provable. There are many reasons
The scientist as an Expert Witness:
Considerations:
The criminalist is not an advocate. He'/she is not trying to “prove” a case
Investigators solve cases
Prosecutors and defenders prove cases
Scientists are objective third parties providing only face
An expert witness must provide information that is
Relevant (material)
Competent
Nothing else
Rule of Admissibility:
There are essentially two standards that govern what experts may present to the court
Frye
Daubert
Frye Standard:
Frye v Untied States, 293 F. 1013 (D.C. Cir. 1923) involved the admissibility of systolic blood pressure deception test as evidence
The court held that expert testimony must be based on scientific methods that are “sufficiently established and accepted”. This is referred to as generally accepted
Daubert Standard:
Daubert v Merrell Dow Pharmaceuticals: 1993 held that Rule 702 of the Federal Rules of Evidence incorporated a flexible reliability standard not general acceptance. In addition the testimony must be relevant
General Electric Co. V. Joiner: 1997 held that expert testimony maybe exclude when there are gaps between the evidence and the conclusion
Kumho Tire Co .v. Carmichael: 1999 held that the judge’s gatekeeping function identified in Daubert applies to all expert testimony, even non-scientific
The Daubert Standard: *
Judge is gatekeeper: Under Rule 702, the task of “gatekeeping” or assuring that scientific expert testimony truly proceeds from “scientific knowledge” rest on the trial judge
Relevance and Reliability: The requires the trial judge to ensure that the expert’s testimony is “relevant to the task at hand”
Scientific Methodology: A conclusion will qualify as scientific knowledge if the proponent can demonstrate that it is the product of sound “scientific methodology”
Derived from hypothesis tested by experiment
The theory or technique is generally accepted in the scientific community
Has it been subjected to peer review and publication
Can be and has it been tested
Is known or potential rate or error is acceptable
Was research conducted solely to provide proposed testimony in the matter at hand
Indiana:
Daubert is instructive
We therefore find Daubert helpful, but not controlling, when analyzing testimony under Indian Evidence Rule 702
Tuner v State
Illinois:
Frye standard
Under the rule of Frye, scientific evidence is admissible at trail only “if the methodology or scientific principle upon which the opinion is based is “sufficiently established to have gained general acceptance in particular field in which it belongs”
People v Mckown
Michigan
Daubert and progeny
Gilbert v DaimlerChrysler Corp
The court must determine whether the experts opinion is reliable and will assist the trier of fact by examining the opinion and its basis, including the facts, technique, methodology, and reasoning relied on the expert and by considering seven factors (look on slide for factors)
Elher v Misra