specific source or person made the unknown print
(inconclusive).
When testifying in court, the examiner must be
able to present the reasons that qualify him or her to
testify as an expert for rendering opinions of judg-
ments of examinations. This qualification requires
the judge’s determination of sufficiency of expertise
based on the training and experience of the witness.
The witness must be prepared to answer questions on
qualifications and on anything to do with the science
and method of latent print examination.Criticism of Fingerprint Evidence
Recently, fingerprint evidence has come under intense
criticism, and below we discuss the different forms of
attack on latent print evidence. Since the United States
v. Byron Mitchellcase of 2003, in which defense attor-
neys began challenging the admissibility of forensic
latent print examinations, fingerprint evidence has
come under attack as an admissible science in the
courts. A major issue surrounding fingerprint evidence
is in the information content that can be extracted and
identified in a latent print. While rolled inked prints
taken under controlled conditions are usually very
clear and rich in detail and information, latent prints
are often inherently less clear, are distorted, and con-
tain considerably fewer details due to the commonly
partial nature of the print itself. It is up to the examiner
to use his or her expertise to determine whether the
latent print contains sufficient information to deter-
mine usability. Then, the examiner determines whether
the details in the inked print and the latent print agree
and have a common source. An individualization is
made when the examiner claims that the two prints
contain a high enough level of similarity that surpasses
the similarity between any two prints from different
individuals. However, determining the level of similar-
ity between two prints is left to the examiner to estab-
lish on the basis of his or her training, skill, and
experience within the forensic comparative science
community. This makes fingerprint evidence some-
what different from DNA analysis, which codes a lim-
ited range of chemical sequences to establish an
identification. Unlike DNA analysis, which has a spe-
cific set of known features, fingerprints can be
matched on the basis of many different types of fea-
tures, including minutiae, ridge flow, and even shapes
of pores. Because the useful features are more diffi-
culty to quantify, it is more difficult to establish aspecific statistical model that would provide the prob-
ability of an erroneous identification. Thus, the proce-
dures include a subjective element, albeit one that can
be verified by third parties. The techniques of compar-
ison and evaluation represent an objective application
of documented procedures.
Despite this lack of statistical models, some exam-
iners have made claims as to the “infallibility” of fin-
gerprints, that identifications are “100% positive,”
and that the error rate of forensic fingerprint identifi-
cation is zero. In fact, to date there have been approx-
imately 20 known cases of misidentifications recorded,
with some involving qualified examiners. Many of
these misidentifications have been so widely publi-
cized that the claim of “zero error rate” and infallibil-
ity has come under serious scrutiny. In addition, a
series of tests conducted from 1995 to 2001 by a pri-
vate independent testing service recorded misidentifi-
cation rates ranging from 3% to 22%. As a result,
authors have pushed for blind proficiency testing to
reduce the amount of erroneous identifications. Many
of these misidentifications are corrected with the use
of additional fingerprint evidence, leading to the pro-
posal that the criticism should fall on individual
examiners rather than the science of latent print
examinations as a whole.Psychological Research
Using Latent Print Examiners
An issue raised recently by Itiel Dror is the possibility
that external sources of information about a case can
affect the decision made by examiners. Known as con-
firmation bias or contextual biases, these sources of
biases originate from knowledge such as whether
other examiners called a particular individualization
or whether other sources of evidence link the suspect
to the crime. Once this information becomes known,
it can be very difficult for an examiner to ignore this
evidence. One fortunate aspect of fingerprints is that,
unlike eyewitness testimony, they represent a form of
physical evidence, and if confirmation is required or
any bias is suspected, testimony from a new examiner
can be sought.
Despite the attacks on fingerprint examiners and the
push for fingerprint evidence to be omitted from the
courts as scientific testimony, several authors have
argued for demonstrable differences between expert
examiners and novices. Recent behavioral and electro-
physiological (electroencephalogram, EEG) research320 ———Fingerprint Evidence, Evaluation ofF-Cutler (Encyc)-45463.qxd 11/18/2007 12:42 PM Page 320