lay opinons and expert testimony Flashcards
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Lay opinion
can offer opinions even on ultimate issues
but must be
rationally based on the witness’ firsthand perception
helpful to clearly understanding the witness’ testimony or helpful in determining a fact in issue
AND not based on scientific, technical, or other specialized knowledge
Expert evidence
A witness who is qualified as an expert may testify in the form of an opinion or otherwise if
The expert’s scientific, technical, or specialized knowlewdge will help the trier of fact to understand the evidence or to determine the fact in issue
the testimony is based on sufficient facts or data
the testimony isthe product of relaible principles and methods the kind typically relied upon by experts in the field
AND the expert has reliably applied the principles and methods to the facts
bases for expert opinion
the expert may base an opinion on facts or data int he case that the expert has been made aware of or personally observed. if the experts int he particular field would reasonably rely on these facts or data in forming an opinion, they need not be admissible for the opinion to be admitted. But if the facts or data would otherwise be inadmissible, the proponent of the opinion may disclose them to the jury only if their probative value in helping the jury evaluate the opinion substantially outweighs the prejudicial effect
Can call an expert ot testify based on an analysts’ reports about a technical issue without having the analysist be in court. no conforntaion clause violation
Reliability factors Daubert
whether the expert’s technique or theory can be or has been tested
whether the technique or theory is subject to peer review and publication
the known or potential rate of error of the technique of theory when applied
the existence and maintenance of standards and controls
Whether the technique has been generally accepted int he scientific community
Reliability factor Frye
Generally accepted test
