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MAKING A CASE
Interviewing Witnesses:
FACE RECOGNITION
Look closely
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Radovan Karadzic

Trying to evade capture for
war crimes in Bosnia he let
his hair grow and wore
spectacles. He was able to
live and work for 12 years
in his country
unrecognised even though
he had been their leader!
Change of appearance

Recognition of faces
is poor if the face
changes between
the encoding and the
presentation of
possibilities.
 This could be a
change in glasses,
hairstyle, beard or
even expression.
Studies of face recognition

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Patterson and Baddeley (1977) compared the
accuracy of recall of a face that had changed
in some way between the first and second
time the participants saw it.
The accuracy of face recall is influenced by:
length of time since the face was seen
the seriousness of crime
the number of previous encounters with the
suspect
witness characteristics (like attention to detail).
Case study:

George Ince was a known gangland
armed robber with links to the Kray
brothers. In 1972 he was tried for a murder
in a case that rested almost entirely on
identification evidence. The witnesses
were the husband and daughter of the
murdered women who saw the attacker for
at least 20 minutes. The daughter
identified Ince from an ID parade, but it
later transpired that she had earlier been
shown his picture contravening the 1969
regulations for the conduct of ID parades.
In 1974 after 2 trials Ince was discharged
as he was able to produce an alibi. This
case highlights the issues that arise with
the investigative process & opens up
some areas for investigation
Photo fits

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Photo fits were first
introduced in the UK
in 1970
They involve trained
operators selecting
alternatives for
specific facial
features to match a
witness’s verbal
description, until they
have produced a
likeness.
Accuracy of Photo fits

This photo fit of Peter Sutcliffe (the Yorkshire
Ripper) was given by one of the women he
raped
 The picture on the right is a photograph of him
taken shortly before his arrest
Advantages & Disadvantages:

Been found to be
very accurate in
many cases
 Use own memory
not multiple choice

Christie & Ellis found
to be less accurate
than verbal
descriptions
Mugshots


When witnesses
experience problems
recalling faces they
may be presented
with a ‘mugshot file’
a collection of photos
of people already
known to the police,
on the assumption
that these photos may
act as a prompt.
Advantages & Disadvantages:

May help prompt
memory / description
as features
 Can save time if
suspect already
know to the police

Feel under pressure
to choose even if not
confident
 Static picture not the
same as live
Show ups

A show-up is the presentation of a photo of
one suspect for the witness to identify
 This is the least satisfactory form of
identification.

DISADVANTAGES:

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May be led to believe the police are very confident
Yarmy found only 57% of people where able to
identify someone from 2mins earlier
Photospreads

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A photospread is more effective than a show –up, as it
involves the presentation of at least 12 faces all
resembling the suspect.
Photospreads would tend to be used in situations
where the police have a suspect in mind, but need a
witness to confirm the identification.
A typical procedure would involve a witness viewing an
array of perhaps twelve photographs and being asked
if they recognised anyone in the array. If the witness
indicated that they did recognise anyone then they
should be asked to say which photograph they
recognise and from where.
Advantages & Disadvantages:

Fairer than a show
up
 Suitable for young
nervous witnesses

Static photos
 Multiple choice affect
 Appearance of foils
may reduce
functional size
Identification Parades (Line Ups)


Perhaps the best-known
type of formal
identification process is
the identification (or ID)
parade.
A suspect stands among
a number of innocent
foils and a witness is
asked to inspect the
parade and then to
decide whether the
perpetrator is present.
Advantages & Disadvantages:

Live better than
photo

Multiple choice affect
 Appearance of foils
may reduce
functional size
 Distressing for
witnesses
 Behaviour (i.e.
nervousness) of
suspect = easier to
identify
Face recognition
Without conferring – write down the
names of the following twelve
celebrities.
Condition A
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Condition A
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Condition A
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Answers - A
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Amanda
Holden
2
Brad Pitt
3
4
Katie Price David
(Jordan)
Tennant
5
Gordon
Brown
6
Cheryl
Cole
7
Johnny
Depp
8
Lindsay
Lohan
9
Mylene
Klass
10
Peter
Andre
11
Nicole
Kidman
12
Simon
Cowell
Condition B
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Condition B
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Condition B
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Answers - B
1
Peter
Andre
2
Mylene
Klass
3
Simon
Cowell
4
Nicole
Kidman
5
Cheryl
Cole
6
Gordon
Brown
7
Lindsay
Lohan
8
Johnny
Depp
9
Brad Pitt
10
Amanda
Holden
11
David
Tennant
12
Katie Price
(Jordon)
Results
People find it easier to recognise the top
half of the face, rather than the bottom
half.
 Why do you think this is?

True or False 1
You need to know 5 aids to recall
 We are better at remembering faces then
snowflakes and inkblots
 Photo fits were first used in the UK in
1980
 2 types of photo fit system are Mac a
Mug and Evofit
 Mugshots are where one photo is given
to a witness

True or False 2
Mugshots lack ecological validity
 Show ups are the least satisfactory form
of identification
 Only 57% of witnesses were able to
accurately identify a person seen 2 mins
earlier in a show up
 At least 10 photos are used in a
photospread
 Photospreads and show ups are
susceptible to the Multiple Choice Effect

True or False 3
ID parades are more suitable than show
ups for young and nervous witnesses
 Cutler & Penrod did a study of a special
kind of ID Parade called a sequential line
up
 Sequential line ups reduce the multiple
choice effect
 Most studies of photospreads use arrays
which do not contain the target

True or False 4
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Photospreads need to be available in court
Photospreads are live, ID Parades use
photographs
Defence council prefers foils who are different
in appearance to the accused
The behaviour of the accused may make him
or her easy to distinguish from foils
If a foil is picked out of an ID Parade they are
arrested
ID parades may be more stressful than the
actual event according to anecdotal evidence
Poor quality CCTV images are still recognisable
Crimewatch etc broadcast appeals directly to people
who know the suspect
3. Implications for facial reconstruction/ e-fits for
approach used
4. Vital components for e-fit. Operators highly trained to
extract relevant info
5. If suspect is seen in poor or side light they may look
very different therefore influencing testimony
6. Facial reconstruction static – future developments
needed
7. Everyone seems to have the ability to recognise faces
– implications for credibility of children as witnesses
8. Implications for reconstructions which tend to be
expressionless
1.
2.
Recognising and recreating faces by E-fit
Key study: Bruce et al. (1988)
Aim
 To investigate the relative recognisability
of internal and external features of a
facial composite.
Method
 Three laboratory experiments.
BRUCE

RECOGNISING FACES

Internal and external features
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Internal features:
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The region including the eyes, brows, nose
& mouth
External features:

Head shape, hair & ears
Participants
1st Experiment – 30 staff and students
from Stirling University, paid £2, 15 male,
15 female, mean age 29
 2nd Experiment – 48 undergraduates at
Stirling University, all volunteers,
21males 27 females
 3rd Experiment – 8 staff and students
from Computer Science and Psychology

Procedure: Experiment 1

The stimuli were target photographs of ten
celebrities and 40 composite images produced
by E-Fit, PRO-fit, Sketch and EvoFIT.
 Each face was clean shaven and spectacles
were avoided.
 Three sets of composites were used:
‘complete,’ a set containing the internal
features and another set containing the
external features.
Procedure: Experiment 1 (cont.)
Participants were tested individually on
one of the three conditions (independent
measures design).
 They were asked to place each
composite in front of a celebrity face in
their own time until the task was
completed.
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Experiment 2
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This experiment used a photo array or photo line up
with distracter faces or foils making the task more
difficult.
The faces and foils were made easy (all very different)
or hard (all very similar) to identify.
The composites were then presented one at a time
along with the photo array and the participant had to
pick out from the array the celebrity face which
matched the composite.
As before, the composites were either of internal
features or external features of the face.
Results
Experiment 1
 Whole composites and those of external features were
sorted similarly at approximately 35% correct. The
composites of internal features were only 19.5%
correct.
Experiment 2
 Composites of external features (42%) were identified
more easily than internal features (24%) and this was
consistent across array type (whether easy or difficult).
Experiment 3
 For both groups the external features were much better
reproduced in the composites
Conclusions

In experiments 1&2 participants performed just
above chance with internal features on the
tasks used. In all cases participants performed
equally well with external features or whole
faces
 This could indicate that there is something
about the internal features of a face which do
not work well when trying to create a
reconstruction.
 This effect holds true even when the face is
familiar which sheds some doubt on previous
research.
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