STANDARDS OF ADMISSIBILITY
Prior to 1993 there were two main standards of
admissibility which had been applied to voice identification evidence; the Frye test and
the Federal Rules of Evidence (and the rules of evidence of the various states). The Frye
test originated from Court of Appeals of the District of Columbia135 in a decision
rejecting admissibility of a systolic blood pressure deception test (a forerunner of the
polygraph test). The court stated that admission of this novel technique was dependent on
its acceptance by the scientific community.
"Just when a scientific principle or discovery crosses
the line between the experimental and demonstrable stages is difficult to define.
Somewhere in this twilight zone the evidential force of the principle must be recognized,
and while courts will go a long way in admitting expert testimony deduced from a
well-recognized scientific principle or discovery, the thing from which the deduction is
made must be sufficiently established to have gained general acceptance in the particular
field in which it belongs".136
Out of forty published opinions prior to 1993 deciding the
admissibility of voice identification evidence, twenty-three courts applied the Frye
standard or a standard very similar to Frye. Sixteen of the twenty-three courts rejected
the admission of such evidence. Six of these courts held the admission of voice
identification evidence by the trial court was harmless error and affirmed the conviction
or judgment. Eight of the sixteen stated that although voice identification evidence had
not yet met the required standard of scientific acceptability, their decision was not
intended to foreclose future admission when such standards were met. Two of these courts
denied admission because they felt a single witness could not speak for the entire
scientific community regarding the acceptance issue.
Seven courts applied the test and found the requirements of
Frye had been met. Of the thirteen courts applying a standard of admissibility different
from Frye, only one, the Free court137, rejected voice identification evidence.
There are three problems with the Frye standard; at what
point is the principle of "sufficiently established" determined, at what point
is "general acceptance" reached, and what is the proper definition of "the
particular field in which it belongs".
These three areas have been major stumbling blocks for the
courts in deciding the issue of the admissibility of voice identification evidence due to
the small number of voice scientists who have performed research in this field. The trial
court in People v. Siervonti 138 noted the lack of research in this area saying "one
only wishes that the last twelve years had been spent in research and not in attempting to
get the method into the courts".139
The Frye test has been criticized as not being the
appropriate test to use for the admission of voice identification evidence. This standard
was established and applied to the admission of a type of evidence which is very different
from voice identification. In Frye the court was concerned with the admission of a test
designed to determine if a person was telling the truth or not. This type of evidence
invades the province of the finder of fact. Voice identification evidence belongs in the
general classification of identification evidence which does not impinge on the role of
the finder of fact. As such it shares common traits with the other identification sciences
of fingerprinting, ballistics, handwriting, and fiber, serum and substance identification.
Another criticism of the application of the Frye test as
the standard for admission of voice identification evidence is that general acceptance by
the scientific community is the proper condition for taking of judicial notice of
scientific facts. McCormick states that general scientific acceptance is a proper
condition for taking judicial notice of scientific facts, but not a criterion for the
admissibility of scientific evidence.140
The court in Reed v. State 141 seemed to note this
difference between the standard for the taking of judicial notice and that for admission
of evidence such as voice identification. The court said that validity and reliability may
be so broadly accepted in the scientific community that the court may take judicial notice
of it. If it can not be judicially noticed then the reliability must be demonstrated
before it can be admitted.142 The court then applied the Frye test, general acceptance by
the scientific community, to determine reliability and thus, admissibility.
Scientific evidence has long been admitted before it was
judicially noticed, as with the case of fingerprints. The admission of fingerprint
identification evidence was first challenged in the case of People v. Jennings143 in 1911.
The court in Jennings allowed the admission of fingerprint evidence saying "whatever
tends to prove any material fact is relevant and competent".144 It was not until
thirty-three years later that fingerprint evidence was first judicially noticed.145
The majority of courts which have decided the issue of
admissibility in favor of allowing voice identification into the courtroom have used
similar standards which permit the finder of fact to hear the evidence and determine the
proper weight to be assigned to it. Their logic runs parallel to the Federal Rules of
Evidence which state that all relevant evidence is admissible with the word
"relevant" being defined as evidence tending to make the existence of any fact
that is of consequence to the determination of the action more probable or less probable
than it would be without the evidence.146 A qualified expert may testify to his opinion if
such opinion will assist the trier of fact in better understanding the evidence.147
Many of the courts which have upheld the admission of voice
identification evidence have done so because the trial court had set up a number of
precautions to insure the evidence was viewed in its proper light. These precautions
include allowing the jury to see the spectrograms of the voices in question, allowing the
jury to hear the recordings from which the spectrograms were produced, the expert's
qualifications and opinions as well as the reliability of the equipment and technique are
subject to scrutiny by the other side, the availability of competent witnesses to expose
limitations in the process, and instructions to the jury that they were free to assign
whatever weight, if any, to the evidence they felt it deserved.
The United States Supreme Court in 1993 changed the
long-standing law of admissibility of scientific expert evidence by rejecting the Frye
test as inconsistent with the Federal Rules of Evidence in the case of Daubert v. Merrell
Dow Pharmaceuticals148. The Court held that the Federal Rules of Evidence and not Frye
were the standard for determining admissibility of expert scientific testimony. Frye's
"general acceptance" test was superseded by the Federal Rules' adoption. Rule
702 is the appropriate standard to assess the admissibility of scientific evidence. The
Court derived a reliability test from Rule 702.
In order to qualify a scientific knowledge, an inference or
assertion must be derived by the scientific method. Proposed testimony must be supported
by appropriate validation - i.e., good grounds, based on what is known. In short, the
requirement that an expert's testimony pertain to scientific knowledge establishes a
standard of evidentiary reliability149
The Daubert decision concerns statutory law and not
constitutional law. The Court held that the Federal Rules, not Frye, govern
admissibility.. The only Federal Circuit to reject spectrographic voice analysis has been
the District of Columbia. Daubert may cause the District of Columbia to change its stance
the next time such evidence is introduced.
Since Daubert is not binding on the states, it will be
difficult to determine just how much impact Daubert will have on the admissibility
standards of the states. Many states have adopted evidence rules based on the Federal
Rules of Evidence and may not be effected by this holding. Other states which have adopted
the Frye test will have to decide to either continue following Frye or change their
standard to Daubert. The Arizona Supreme Court declined to follow Daubert saying that it
was "not bound by the United States Supreme Court's non-constitutional construction
of the Federal Rules of Evidence when we construe the Arizona Rules of Evidence."150