Texas Forensic Science Seminar 2010
Judge Cynthia Stevens Kent
• RULE 702/705 HEARINGS ON
ADMISSIBILITY OF EXPERT
• WHEN TO HEAR:
– PRE-TRIAL EARLY OR LATE?
– DURING TRIAL WHEN WITNESS IS
– DURING DAY OR AT EVENING BREAK?
• DAUBERT ISSUES
• TRIAL JUDGE IS THE GATEKEEPER
• Experts are people who know a great deal about
very little, and who go along learning more and
more about less and less until they know
practically everything about nothing.
• Lawyers, on the other hand, are people who know
very little about many things, and who keep
learning less and less about more and more until
they know practically nothing about everything.
• Judges are people who start out knowing
everything about everything, but end up knowing
nothing about anything, due to their constant
association with experts and lawyers.
• FRYE TEST OF “GENERAL
ACCEPTANCE” IS NO LONGER THE
RULE FOR DETERMINING
ADMISSIBILITY OF RULE 702
• TRIAL COURT JUDGE WILL BE
GATEKEEPER AND DETERMINE IF THE
PROPONENT OF THE EVIDENCE
• UNDERLYING THEORY IS VALID
• TECHNIQUE APPLYING THE THEORY
• TECHNIQUE WAS PROPERLY APPLIED
ON THE OCCASION IN QUESTION
• EXTENT TO WHICH THEORY IS
ACCEPTED AS VALID BY RELEVANT
• QUALIFICATIONS OF EXPERT
• EXISTENCE OF LITERATURE
SUPPORTING OR REJECTING
FACTORS - CONTINUED
• POTENTIAL RATE OF ERROR
• AVAILABILITY OF OTHER EXPERTS TO
• CLARITY OF EXPLAINING THIS
• EXPERIENCE AND SKILL OF PERSON
WHO APPLIED TECHNIQUE
LAY OPINION TESTIONY
• A NON EXPERT MAY GIVE AN OPINION
IF IT IS RATIONALLY BASED ON
PERSONAL KNOWLEDGE AND IT IS
HELPFUL TO A CLEAR
UNDERSTANDING OF THE WITNESSES
TESTIMONY OR A FACT IN ISSUE
(EVEN ULTIMATE ISSUE)
• Opinion must be:
1. Based on personal knowledge (TRE 602)
2. Rational connection between opinion and
facts upon which it is based (nexus)
3. Must be helpful in understanding the
testimony or determining a fact in issue
4. Not based upon knowledge within scope
of TRE 702 (amendment)
• TRE 701 is a significant departure from
the American common law which
precluded lay witnesses from giving
• Evolution from recent common law to TRE
701: Courts tried to draw distinctions
between fact and opinion inferences or
conclusions. Drafters thought this was too
difficult or contrived.
PURPOSE OF 701
• Common law prohibition on lay opinion
testimony was based partly on the
assumption that facts and opinions are
easily distinguishable and partly on the
notion that jurors are as well equipped to
draw inferences from the facts supplied by
a lay witness as is the witness.
• TRE 701 abandons the common law’s
nominally rigid approach to lay testimony
LAY VS. EXPERT
• The last clause of 701 precludes litigants
from offering expert testimony under the
guise of lay opinion testimony as a means
of evading the discovery and reliability
requirements associated with expert
• TRE 701 now makes it clear that there is
no overlap between 701 and 702.
Opinions must be rationally based
on witness’s perception
• Two elements required:
– 1. Personal knowledge requirement of
– 2. Mandate that the opinion must be one
that a reasonable person could draw
from the underlying facts.
These requirements eliminate lay opinions
based on hearsay, speculation, and irrational
Helpful Requirements Test
1. The extent to which the testimony goes to the
heart of the case.
2. The amount of factual matter subsumed in the
3. The ability or inability of the witness to convey
the information in the form of specific facts.
4. The extent to which the jury is equally well-
positioned to draw the inferences from the
5. The need for the testimony.
TRE 704: Opinion on
• Testimony in the form of an opinion or
inference otherwise admissible is not
objectionable because it embraces an
ultimate issue to be decided by the trier of
fact except in a criminal case where
mental state is an element of the crime
TRE 704 (Continued)
• Removes the court from determining whether an
opinion goes to the ultimate issue and eliminates
“invades the province of the jury” and “ultimate
• Need to do a TRE 701 or TRE 702 and TRE 403
analysis to determine admissibility. Court still
permitted to exclude lay or expert opinions on
issues of “fault,” “negligence” or “guilt” due to fact
that opinion is not “helpful” or unnecessary per
TRE 701 or TRE 702, and TRE 403
Opinions held inadmissible
• An expert’s opinion about accused’s guilt. U.S.
v. Alonso, 48 F.3d 1536 (9th Cir. 1995)
• Expert may not testify as to an accused mental
state or condition that constitutes an element of
a crime charged or a defense to the crime
charged. See U.S. v. Bennett, 161 F.3d 171 (3
• But may testify that accused suffered from
mental disease or defect to the describe
characteristics and effects of such disease or
• Frye test: “General acceptance”
• TRE 702: Frye + assist standard
• Daubert Test: Reliability + relevance
• Daubert progeny
• TRE 703 Bases of expert opinion
• TRE 704 Opinion on ultimate issue
• TRE 705 Disclosure of data or facts
• TRE 706 Court appointed experts
ROLE OF THE EXPERT
*The New WIGMORE
• The purpose of expert testimony is to provide
the trier of fact useful, relevant information.
• Expert need not be a member of a learned
• Expert have wide range of credentials and testify
regarding a tremendous variety of subjects
based on their skills, training, education or
METHOD OF QUESTIONS
1. Experts may be questioned about general
principles that would advance the jury’s
understanding of the facts in dispute.
2. Experts may be asked to offer their own
opinions based on their firsthand investigations
and to describe certain observations they have
made aided by their expertise.
3. Experts may be asked to provide opinions
based on facts specific to the case but outside
their personal knowledge.
HOW FACTS PROVIDED
• Facts can be supplied by the testimony of
ordinary witnesses and known to the
expert because the expert was present
during their testimony.
• Alternatively, the expert may be asked to
state an opinion based on hypothetical
questions incorporating a party’s version
of the facts as testified to by these other
Facts not in Evidence
• Often experts rely on
that is not itself in
• Experts are provided exemptions from rules to
which other witnesses must adhere.
• Experts are not bound by the requirement that
testimony be based on personal knowledge.
• Experts may serve as conduits for hearsay so
long as others in the same field reasonably rely
on such hearsay.
• Experts have been largely immune from perjury
charges. BUT NOT ALWAYS.
Experts: Frye Test
• Frye v. United States 293 F. 1013 (D.C.
• “General acceptance” test
• The proponent must show that the theory
and scientific evidence have been
generally accepted within the relevant
*The New Wigmore
• Scrutiny of scientific as oppose to other
forms of expert testimony began in 1923
with the FRYE standard of general
FACTS OF FRYE
• James Frye was charged with murder. He
sought to introduce testimony of
psychologist who had administered a
systolic blood pressure test to the
defendant. The “expert” wanted to testify
that the test revealed that Frye was truthful
when he denied committing the murders.
• *Forerunner of lie detector test.
• Court ruled that the technique was too
speculative. It found that other
psychologists had yet to accept the claim
of verifying honesty by measuring blood
• Subject of expert testimony must have
gained general acceptance in the
particular field to which it belongs.
• General acceptance test tended to screen out evidence.
In a variety of cases it resulted in excluding the following
types of evidence:
– Polygraph evidence
– Hypnotic and drug induced testimony
– Voice stress analysis
– Voice spectrograms
– Infrared sensing of aircraft
– Blood alcohol tests
– Polarized light microscopy
– Psychological profiles of battered women
– Post Traumatic Stress disorder as indicating rape
– Ear prints
Expert’s Opinion of Frye
• General acceptance standard never was
popular with evidence scholars.
• Frye failed to provide uniformity in court’s
rulings on admissibility.
• Frye shifted the evaluation of expert
testimony reliability by the judge and jury
to the general acceptance of such expert
testimony within a certain field of study.
TRE 702: Testimony by
• TRE 702: If scientific, technical, or other
specialized knowledge will assist the
trier of fact to understand the evidence
or to determine a fact in issue, a witness
qualified as an expert by knowledge,
skill, experience, training, or education,
may testify thereto in the form of an
opinion or otherwise.
• 1993 U.S. case Daubert v. Merrell Dow Pharm,
Inc. 509 U.S. 579 (1993) held that the FRYE test
did not survive the promulgation of the F.R.E.
• The Supreme Court emphasized that the
evidentiary rules provided for a flexible inquiry
into the scientific validity of principles made the
basis of an expert’s opinion, but that the court
must make the preliminary determination of the
admissibility of such expert testimony.
• Trial Court under TRE 702 must make a
preliminary assessment of whether the
reasoning or methodology underlying the
expert testimony is “scientifically valid and
of whether that reasoning or methodology
properly can be applied to the facts in
• Trial judges are gatekeepers of expert testimony
admissibility in both criminal and civil cases.
• TRE 702 and TRE 104 requires that the court
must determine whether the proponent of the
proffered expert testimony has demonstrated by
clear and convincing evidence that the expert
– 1. Reliable
– 2. Relevant
• To be reliable, the proponent must prove
1. The underlying scientific theory is valid,
2. The technique applying the theory is
3. The technique was properly applied on
the occasion in question.
• In determining reliability the court may
consider factors, non-exclusive list:
1. Extent to which the underlying scientific
theory and technique are accepted as valid
by the relevant scientific community, if such
a community can be ascertained.
2. The qualifications of the testifying expert
3. Existence of literature supporting or rejecting
the underlying scientific theory and
• In determining reliability the court may
consider factors, non-exclusive list-
4. Potential rate of error of the technique
5. The availability of other experts to test and
evaluate the technique;
6. The clarity with which the underlying scientific
theory and technique can be explained to the
7. The experience and skill of the person who
applied the technique on the occasion in
• If the Court determines the evidence is
RELIABLE - then the trial judge must
then determine if the evidence is
RELEVANT to the determination of a fact
issue which if of consequence in the
• Then the balancing test must be applied.
• Daubert envisioned a flexible inquiry
focusing solely on the underlying
principles and methodology not on the
conclusions they generate.
• Judges do not have to be trained in
science to evaluate the reliability of a
theory or technique and are capable of
understanding and evaluating scientific
• Judges have limited formal training or
practical experience in the use and
evaluation of scientific methodology.
• “Daubert Readiness of Texas
Judiciary…” 6 Tex. Wesleyan L.R. 1 (Fall
1999) – Authored by Yours Truly
• Criteria for admissibility:
– Will the specialized knowledge assist the
trier of fact?
– What is the evidence?(Fingerprint, DNA,
– What is the issue?
– What is the state of the art?
– Although admissible, should it be excluded
under TRE 403
– Is the witness qualified:
• Knowledge/ skill/ experience/ training/education
The Evolution of TRE 702
• The judicial response to TRE 702 and
• Ex. Many states struggled and defined
general acceptance prong of Frye to
include such things as peer review,
publication, independent validation and
testing, etc…. and tried to reconcile the
two competing standards.
• The “reliability” standard: United States v.
Downing, 753 F.2d.1 224( 3rd Cir. 1985)
• Daubert v. Merrell Dow, 113 S.Ct. 2786 (1993).
Supreme Court held that the rules do not give
any indication that “general acceptance” is a
necessary precondition to the admissibility of
scientific evidence. “General acceptance” is a
factor but is not dispositive.
– can be tested
– peer review & publication
– known or potential error rate
– wide spread acceptance
• NEW FORMULA: QUALIFICATIONS +
(RELEVANCE AND RELIABILITY) =
Split of Authority in the
• Some Federal Circuit Courts of Appeal
limited Daubert to novel scientific expert
opinion testimony others gave it broad
Daubert Progeny: Federal
• Daubert II (added new criteria on remand)
• Lacobelli Const. V. Monroe ( 3rd Cir. limited scope)
• Berry v. Detroit ( 6th Cir. expanded view)
• U.S. v. Bonds (6th Cir. admissible under Frye and Daubert)
• U.S. v. Starzecpyzel ( DC NY limited view but let in because Daubert
didn’t apply to other parts of the rule)
• In re Paoli R.R. Yard PCB litigation( 10th Cir added new criteria)
• U.S. v. Posado (5th Cir. ought to reconsider polygraph under new
• U.S. v. Scheffer ( Daubert/ polygraph/ MRE 707)
• Compton v. Subaru (10th Cir. Daubert didn’t apply to design defect
• U.S. v. Sinclair (limited view)
• Ninth Circuit Split: Southland Sod (broad)/ Webb(limited)
TRE 703: Bases of Opinion
Testimony by Experts
• The bases of opinion testimony may include
hearsay. “ If a type reasonably relied upon by
experts in the particular field in forming opinions
or inferences upon the subject, the facts or data
need not be admissible in evidence.”
• See also TRE 803 (18) Learned Treatise
• Significant departure from the common law. Under
common law could not rely on inadmissible
hearsay. TRE 703 permits expert to rely on
TRE 703 (continued)
• Third great hearsay exception
703 – Bases of Opinions
• Facts within knowledge
• Facts presented to expert at trial
• Facts presented to expert out of court, not
in evidence, but reasonably relied upon by
experts in the field.
Otherwise Inadmissible facts
• May be considered in experts opinion
• Before the court allows disclosure of such
facts to the jury, the court must determine
that their probative value substantially
outweighs their prejudicial effect. Just
because the expert may use this
information does not always mean that
those inadmissible underlying facts are
admissible through the expert’s testimony.
Opinions on Prohibited Data
• Data obtained in violation of law or
constitution cannot be the basis of expert
opinion. See. Estelle v. Smith, 451 U.S.
• Even in civil cases. See Robertson v.
Union Pacific RR Co. 964 F.2d 1433 (8th
• JUST ‘CAUSE YOU’RE
FOLLOWING A WELL-
MARKED TRIAL . . . DON’T
MEAN THAT WHOEVER
MADE IT KNEW WHERE
THEY WERE GOIN’.
» Texas Bix Bender
TRE 705: Disclosure of Facts
or Data Underlying Expert
• An expert does not need to disclose underlying
facts or data before giving an opinion or the
reasons for that opinion. The expert may be
required to disclose underlying facts and data on
• Issue:Does the hypothetical question survive in
light of 705 and 703?
ADMISSION OF UNDERLYING
• If facts are admissible then allow
disclosure with no limiting instruction
• If facts are inadmissible they possess
probative value only if they may help the
jury to evaluate the expert’s opinions.
Court has several opinions in this
INADMISSIBLE FACTS OPTIONS
1. Allow expert to disclose the inadmissible
underlying facts and then give a limiting
instruction to the jury. See. Brennan v..
Reinhardt Institutional Foods 211 F.3d
449 (8th Cir. 2000).
INADMISSIBLE FACTS OPTIONS
2. Restrict the expert to a description of the
types of underlying data upon which he
relied, but not allow the expert to give
any details. See Marsee v. U.S.
Tobacco Co. 866 F.2d 319 (10th Cir.
INADMISSIBLE FACTS OPTIONS
3. Prohibit any mention of the otherwise
Opposing counsel may not use cross-
examination as a means of bringing
inadmissible hearsay or opinions before the
jury. Thus counsel may not bring before the
jury inadmissible hearsay reports or data to
impeach testifying expert if expert did not rely
on material in question.
TRE 706: Court Appointed
• TRE 706 permits court to appoint experts.
Make certain you follow procedure set
forth in the rule otherwise it might result in
disqualification due to an ex parte contact.
• Procedure for appointment
– Court may appoint sua sponte or on motion of party
– Notice to parties is required
– Court expert may be deposed
– Either party may call court appointed expert
– Compensation in amount allowed by court
– Court may authorize disclosure that this is court
– Parties may still have their own experts
•LET’S LOOK AT
Physical and Chemical
• Tests derived from the physical and
biological sciences and requiring
sophisticated laboratory instruments are
uniformly treated as meriting special
Mathematical and Statistical
• Although not involving sophisticated
laboratory instruments, mathematical and
statistical models can be inscrutable and
impressive to those not schooled in these
areas and might seem to qualify for
heightened scrutiny of TRE 702.
Dog Sniff Evidence - Tracking
• No strict standard of either Frye or Daubert
needed in dog tracking evidence. See Brooks v.
People, 975 P.2d 1105 (Colo. 1999).
• Use general standards for expert testimony.
See Winston v. State, 78 S.W.3d 522 (Tex.Ct.
• Special scrutiny when used as substantive proof
of an accelerant in a fire.. See State v Schultz,
58 P.3d 879 (Utah Ct. App. 2002)
Tests for Drunkeness
• Blood samples chemical analysis: look to
proper laboratory procedures being
followed and sample correctly obtained
and preserved then reliable estimates for
BAC can be proven. Extrapolations back
to time of driving is more complex. Breath
tests are even more challenging but the
scientific cautions does not make blood
and breath test inadmissible.
• Mosiac of laws and rules for testing and
admissibility of testing across the country
which are superimposed on the more
general evidence code or common law
Blood, Tissue and DNA Types
• Many of these tests have gained such
scientific acceptance that the courts may
take judicial notice of their scientific
acceptance and reliability.
• For some time there was considerable
debate in court about the admission of
• 99.9 percent of the DNA sequence in any
two people is identical. DNA testing is
looking to detect the relatively rare
stretches of DNA called alleles that vary
among individuals. Various procedures for
• First decade of DNA testing used typing
procedure RFLP (restriction fragment
• Following the initial wave of acceptance of
RFLP testing the defendants pointed to
problems of controlling the experimental
conditions of analysis and of interpreting
the results. Courts became more critical in
their scrutiny of this evidence but still it
was generally admitted.
• The attack on DNA profiling lead to cases where
the courts held that estimates of the probability
of a coincidentally matching VNTR (variable
number of tandem repeats) were inadmissible.
• More research was done and the National
Academy of Sciences in 1996 concluded that the
usual method of estimating frequencies of VNTR
profiles in broad racial groups was sound. Court
responded with general admissibility.
• PCR (polymerase chain reaction) – based
testing, small portions of DNA molecules
are amplified by heating and cooling with
an emzyme called DNA polymerase.
There is general court acceptance that the
more commonly used PCR-based
procedures satisfy TRE 702 standards.
• This is the current status of DNA testing.
• Started as a fertile area of 702 litigation but
has now settled down to a reliable expert area
based on good scientific methodology.
• This type of expert testimony is generally
accepted. See U.S. v. Ferri, 778 F.2d 985
(1985) cert. denied.
• Generally admissible.
• Techniques are generally accepted.
• Look to method of extraction, taking of
• Computer analyzed
• Generally accepted.
• But I suggest you look at this for TRE 702
TYPES OF EXPERTS
• Psychiatric Experts
• Use is limited only by
• Psychological Experts
• You can find one for
any opinion but
TYPES OF EXPERTS
• Look to the specifics of
• Porter v. Whitehall Lab.
9 F.3d 607 (7th Cir.
1998) Theory linking
ingestion of ibuprofen
to renal failure was
• Jackson v. State 992
• and Rey v. State, Id.
• Pathologist in capital
case which the
mechanism of death
was a significant
• Look at scientific
• Courts generally rejected polygraph
evidence. There was a number of courts
who took a fresh look at the evidentiary
value of the most commonly used polygraph
• However there is a widespread and strongly
rooted reluctance to permit polygraph
evidence in that the technique is not
generally accepted in the scientific
community as reliable.
• Generally this evidence is excluded as it will
not aid the jury because the credibility of a
witness is susceptible to resolution without
expert testimony. This area invades the
province of the jury.
• However there is limited acceptance based
on stipulation or for impeachment or
corroboration in some jurisdictions.
• U.S. v. Posado, 57 F.3d 428 (5th Cir. 1995)
rejected a per se rule of exclusion.
• U.S. v. Cordoba, 194 F.3d 1053 (9th Cir.
1999) affirmed finding of unreliability.
• U.S. v. Prince-Oyibo, 320 F.3d 494 (4th Cir.
2003) affirmed per se rule of inadmissibility.
• LOOK TO YOUR STATE STATUTES
• Jackson v. State
• 992 S.W.2d 449
• Tex.Crim.App. 1999
• Defendant not entitled to assistance of state
funded polygraph examiner - No consensus
that polygraph evidence is reliable or
• Court are most reluctant to admit this type
• Eye witness identification
experts are generally
province of jury.
• See U.S. v. Langan, 263
F.3d 613 (6th Cir. 2001)
• Might be an area for
consideration if a
significant factor in
the State’s case and
they have a “gang
• Look carefully at
EXPERTS ALLOWED IN
• Drug Analysis
EXPERTS ALLOWED IN
• Jury selection (not in Texas)
• Questioned documents
EXPERTS ALLOWED IN
• Statistics and Demography
Grounds for finding lack of
reliability or helpfulness
• Lack of relevance
• Expert testimony not needed
• Based on speculative or incomplete data
• Questionable theories
• Too conjectural
• Too great gap between data and opinion
• Beyond expertise
• What do you think?
• Look at the evidence the state is
presenting and consider what experts
would be HELPFUL