Describe and evaluate research that has investigated the infl uence of
anxiety on the accuracy of eyewitness testimony
Johnson and Scott conducted a study to investigate how high levels of anxiety in a
situation can affect accuracy in an eyewitness testimony. In this study, participants were
asked to wait in a reception with a receptionist, until they were called for their turn for
the ‘study’. The receptionist then left the room, leaving them alone. There were two
conditions in this study: a weapon condition and a non-weapon condition. The weapon
condition was expected to cause high levels of anxiety, and the non-weapon condition
the opposite. In both conditions, participants heard a heated argument and a loud bang
in a separate room to them. In the weapon condition, after the loud bang, a person
walked out of the room holding a bloodied letter opener and looking very flustered. In
the non-weapon condition, the person walked out holding a pen and covered in oil.
After being asked to identify the person who left the room from a selection of 50
photos, 49% of the non-weapon condition identified them correctly and only 33% of the
weapon condition identified them correctly. This suggests that the high anxiety levels
caused by seeing a weapon can affect the accuracy of an eyewitness testimony. This is
called the ‘weapon focus effect’.
A strength of Johnson and Scott’s study is the use of the independent groups design.
This experimental design means that the results are unlikely to be affected by order
effects and demand characteristics. Participants are less likely to become fatigued
through the experiment as they are only going through one condition. This also means
that the likelihood of demand characteristics affecting the results is reduced. If the
participants went through both conditions (Repeated measures) then they would be
much more likely to guess the aims of the study and doubt its authenticity.
A limitation of Johnson and Scott’s study is that it has ethical issues where multiple
guidelines happened to be broken. One guideline that was broken is that the
participants were deceived. To avoid them guessing the aims of the study, Johnson and
Scott neglected to reveal the true nature of the study. This could have led to the
participants feeling humiliated. The participants were also not protected from harm.
The high levels of anxiety caused by witnessing a bloody weapon could lead to
exceptional levels of stress being left on the participant. This could have been even
more serious if any of the participants had been involved in a traumatic incident
involving knives.
Another limitation of Johnson and Scott’s study is that there is contradicting research.
Yuille and Cutshall interviewed 13 witnesses of a real life shooting where someone was
killed four to five months after the incident. These interviews were then compared to
the original police interviews that the participants had undertaken. They found that all
the major details from the interviews were the same. The only details that varied were
the rough age, height and weight of the culprit. The anxiety levels of the witnesses had
no effect on their recall of the event months later, and so these findings contradict
those of Johnson and Scott.
anxiety on the accuracy of eyewitness testimony
Johnson and Scott conducted a study to investigate how high levels of anxiety in a
situation can affect accuracy in an eyewitness testimony. In this study, participants were
asked to wait in a reception with a receptionist, until they were called for their turn for
the ‘study’. The receptionist then left the room, leaving them alone. There were two
conditions in this study: a weapon condition and a non-weapon condition. The weapon
condition was expected to cause high levels of anxiety, and the non-weapon condition
the opposite. In both conditions, participants heard a heated argument and a loud bang
in a separate room to them. In the weapon condition, after the loud bang, a person
walked out of the room holding a bloodied letter opener and looking very flustered. In
the non-weapon condition, the person walked out holding a pen and covered in oil.
After being asked to identify the person who left the room from a selection of 50
photos, 49% of the non-weapon condition identified them correctly and only 33% of the
weapon condition identified them correctly. This suggests that the high anxiety levels
caused by seeing a weapon can affect the accuracy of an eyewitness testimony. This is
called the ‘weapon focus effect’.
A strength of Johnson and Scott’s study is the use of the independent groups design.
This experimental design means that the results are unlikely to be affected by order
effects and demand characteristics. Participants are less likely to become fatigued
through the experiment as they are only going through one condition. This also means
that the likelihood of demand characteristics affecting the results is reduced. If the
participants went through both conditions (Repeated measures) then they would be
much more likely to guess the aims of the study and doubt its authenticity.
A limitation of Johnson and Scott’s study is that it has ethical issues where multiple
guidelines happened to be broken. One guideline that was broken is that the
participants were deceived. To avoid them guessing the aims of the study, Johnson and
Scott neglected to reveal the true nature of the study. This could have led to the
participants feeling humiliated. The participants were also not protected from harm.
The high levels of anxiety caused by witnessing a bloody weapon could lead to
exceptional levels of stress being left on the participant. This could have been even
more serious if any of the participants had been involved in a traumatic incident
involving knives.
Another limitation of Johnson and Scott’s study is that there is contradicting research.
Yuille and Cutshall interviewed 13 witnesses of a real life shooting where someone was
killed four to five months after the incident. These interviews were then compared to
the original police interviews that the participants had undertaken. They found that all
the major details from the interviews were the same. The only details that varied were
the rough age, height and weight of the culprit. The anxiety levels of the witnesses had
no effect on their recall of the event months later, and so these findings contradict
those of Johnson and Scott.
