Describe what psychologists have found out about the psychology of testimony?

There are many different variables influencing an accurate identification. Some variables that might be influentional are things such as memory. Other variables Wells describes as estimator and system variables. Estimator variables (variables the judicial system has no control over, i.e. stress) include things such as weapon focus. Weapon focus is the idea that a witness will focus more closely on the weapon than on the person holding the weapon. This could be because of the danger of the weapon or because of the unusualness of the situation the person is put in. Loftus et al. conducted an experiment to see what the effects of weapon focus were. Participants were split into two groups and showed one of two films in one a customer was holding a gun in a restaurant and in the other the customer was holding a cheque. In an identity parade and answers to questions the participants who saw the film with the cheque were more accurate in their identification and answers then those who saw the film with the gun. Loftus therefore concluded that this was caused by weapon focus, which was displayed in the gun condition. System variables on the other hand are things in which influence testimony over which the judicial system has some control (such as questioning techniques). Questioning techniques can lead to a change in the perception/recall of an event. Loftus and Palmers work on leading questions shows this. They said that there are two parts to people’s memory. The first is what the person perceived at the time of the event and the second is information gathered after the event has occurred. These two stages fuse together into one memory that becomes the truth about the suspect/event.

Many different aids are available for witnesses to recall an event and to assist with the recognition of a suspect. The cognitive interview technique is widely used. They are useful with both witnesses and victims. Fisher and Geiseman devised the technique in 1984. They said that police could discourage the witness form remembering all they can by asking closed questions or by interrupting the witness. They said that the witness feels powerlessness and the police has the dominant role, the cognitive interview tries to breakdown this relationship. Fisher and Geiseman suggest that if the witness is put at ease and allowed to take the dominant role, they more likely give as much information as they can. A cognitive interview consists of the witness being encouraged to relate their whole story without interruption while the police officer has an active listening role. There are four stages in a cognitive interview which are: -

• Recreating the context
• Focused concentration
• Multiple retrieval attempts
• Varied retrieval

Identity parades/line ups are used to assist with the recognition of a suspect. They try to enable the witness to pick out the person they thought was involved in an offence. This it can be useful, but there are various ways in which the witness can be led during an identify parade. The simple wording of the information that accompanies the parade, it should be made clear to the witness that likeness is not enough and that the person they may not be there, this information should be made clear all witnesses.

Psychologists have found out many different things and have many different theories regarding psychology of testimony. Some things they have found out have been to do cognitive processes which include the acquisition of what happened and how the witness perceived the event, retention which is how much time is between the event and giving evidence and retrieval, being able to recall the event when giving evidence. The variables influencing accurate identification of the suspects which includes estimator values, such as weapon focus and system variables which is things such as questioning techniques which can lead witnesses giving an answer which isn’t actually what happened.  Finally the aids used to recall the event and recognition of the offender, psychologists have found out that the best way to get the most information out of witness is to use cognitive interviews and to let them take a dominant role. They have also found out that identity parades aren’t always 100% useful as witnesses sometimes do pick people just because they think the person who committed the crime is there, when the may not be.