identifications were used as evidence. But a growing
body of research suggests that the use of voice identi-
fications in court is just as dangerous, if not more so,
than reliance on eyewitness identification. Research
consistently shows that voice recognition is less accu-
rate than face recognition under similar circumstances
and that the same factors that affect eyewitness relia-
bility can also create problems for the earwitness.
Potential jurors, however, often overestimate the accu-
racy of voice recognition in forensic contexts.Voice Recognition
in the Courtroom
Perhaps the most famous use of voice recognition evi-
dence in a criminal trial was in the trial of Bruno
Richard Hauptmann, executed in 1936 for the kidnap-
ping and murder of the infant son of the aviator Charles
Lindbergh. The Lindbergh case was called the trial of
the century, and one of the most dramatic moments in
the trial was when Lindbergh himself took the stand.
Describing the night of the ransom drop-off 3 years
before the trial, Lindbergh spoke of hearing a voice
from 100 yards away while he waited in his car for a
friend to hand over the ransom. When Hauptmann was
arrested 29 months later, Lindbergh was brought to the
police station to listen to Hauptmann repeat the words
of the kidnapper: “Hey doctor! Over here, over here.”
Lindbergh testified under oath that he was certain that
Hauptmann’s voice was the voice of the kidnapper.
Experts still disagree over whether the jury reached the
correct verdict in finding Hauptmann guilty.
Voice identification has played a role in at least one
well-publicized case of erroneous conviction in Canada.
In October 1984, a 9-year-old girl named Christine
Jessop disappeared from her home in Ontario and was
found dead almost 3 months later. She had been stabbed
to death, apparently shortly after her disappearance. The
investigation quickly focused on a neighbor, Guy Paul
Morin, who was arrested in April 1985. Although Morin
had a strong alibi, he was brought to trial in 1986 and
was initially acquitted. But in Canada, the prosecution
can appeal an acquittal, and Morin was retried in 1991.
The second trial lasted almost 9 months, and the second
jury found Morin guilty.
Although many errors occurred in the investigation
of Christine Jessop’s death and the trials of Guy Paul
Morin, one dramatic piece of evidence at the trial came
from Christine’s mother, Janet. She testified that on the
night of Christine’s funeral, she heard an unknown male
voice crying out near her home, “Help me, help me, ohGod, help me!” She later identified this voice as that of
her neighbor, Morin, with whom she had spoken over
the fence just a few times. The prosecution claimed that
Morin experienced a fit of remorse after the funeral and
cried out in emotional agony from his home. While we
cannot know the role that this testimony played in the
jury’s decision, one thing is clear: The wrong man was
ultimately convicted. DNA testing revealed several
years later that Morin could not possibly be the killer,
and he was exonerated in 1995. The real killer has never
been found.Earwitness Research
Morin’s voice was mistakenly identified by a casual
acquaintance. Lindbergh, in contrast, was called on to
identify a voice that he had heard only once. Both types
of identification have forensic relevance. Usually, voice
identifications are made in situations in which the wit-
ness or victim was unable to see the perpetrator’s face
because of darkness or because the perpetrator wore a
mask. Sometimes, the victim of a crime may recognize
the perpetrator’s voice as that of a former co-worker or
even a relative. The victim tells the police that he or she
recognized the voice, and the identified person
becomes the main suspect. Many cases in which voice
identification is used as evidence, however, involve the
identification of a stranger’s voice. In such cases, when
a suspect has come to light, a voice lineup may be
played for the witness, usually in the form of a tape-
recorded series of short clips of several parties speak-
ing. The witness is asked to indicate whether any of the
voices is the voice of the perpetrator. A voice showup
may also be used, in which the witness is asked to lis-
ten to only one voice and to indicate whether this voice
is the voice of the perpetrator. For example, witnesses
to a bank robbery in North Carolina were asked to lis-
ten to a tape-recording from a previous convenience
store robbery, in an effort to gather evidence that the
two crimes were committed by the same person.
Why would such identifications result in errors? As
with face recognition by eyewitnesses, it is important to
recognize that memory for a voice does not operate like
a tape recorder or a video camera. A listener encodes
certain salient features of a voice into memory (e.g.,
pitch, loudness, accent, or unusual pronunciation or
cadence) when it is heard, but later recognition of the
voice as familiar is also heavily influenced by context,
expectations, and logical reasoning. For example, if
you answered your telephone right now, your identifi-
cation of the voice at the other end of the line would852 ———Voice RecognitionV-Cutler (Encyc)-45463.qxd 11/18/2007 12:44 PM Page 852