Interview Techniques

Interview Techniques

1. Interrogation Variables

   • Retention Interval
     • Delay between the crime and the time the witness describes what happened, ranges from minutes to months/yeas, with clear consequences for memory
       • In Melbourne, over half of witnesses are interviewed > 3 days after the crime was committed
     • The case of 'Ivan the Terrible' illustrates the difficulties in prosecuting crimes following a prolonged retention interval
       • In 1988 John Denmjanjuk was tried, convicted and sentenced to death as a Nazi war criminal
       • Always protesting his innocence, he was deported from the US after being identified as Ivan the Terrible by nine elderly witnesses
       • Following the collapse of the Soviet Union, access to wartime archives shoed that the real Ivan the Terrible was Ivan Marchenko who had been killed in the 1960s, Denmjanjuk was freed
   • Type of Recall
     • Typically a witness is asked to report everything they saw during the incident, in their own words, at their own pace (free recall)
     • This is followed by interrogative recall, where the police ask cued questions to gain further info/clarification
       • Interrogative recall, including structured questions/interview protocols, produces a greater range of info than free recall, BUT is less accurate than free recall particularly when dealing with difficult info
   • Number of Recalls
     • Witnesses are 'never' asked to recall the incident only once, they are repeatedly required to go over their account
       • Increases in cognitive effort enhance the quality of the recall
     • Hypermnesia is the phenomenon of improved recall following repeated testing
     • "Multiple eyewitness recalls can be beneficial in terms of overall recall without a severe increase in errors"
       • It is presumed that by repeatedly attempting to access their memory, witnesses obtain more samples from the range of info traces available for the event, increasing the availability of retrieval cues
     • However, repeatedly asking witnesses to go over the retrieved info can cause other problems
       • Odinot et al. demonstrated that whilst repeated post-event questioning does not induce forgetting of related info, retrieval practice does enhance confidence ratings
       • Confidence in BOTH correct and incorrect info is enhanced by repeated questioning: an effect known as confidence inflation
       • As such, they recommend that "repeated questioning be avoided if at all possible"
   • Post-event Interference
     • After witnesses have given a verbal description of the subject they are often asked to help make a photofit or artist's impression, to examine mugshots, and to identify the suspect in a lineup
       • All of these activities will influence the witness's subsequent memory of the suspect
     • Planting misinformation in a police interview has been found to have a profound effect on witness's subsequent recall
       • Having initially seen a man with a moustache, straight hair, carrying a can of coke and a box of cereal, misinformation led the participants to recall the man as being clean shaven with curly hair, carrying a can of peanuts and a box of eggs
     • Leading Questions
       • People exposed to misleading post-event information report the misinformation on subsequent memory tasks with confidence
       • Loftus and Palmer asked participants to watch a film of a car accident and estimate the speed at which the car crashed, estimates of the speed varied according to the verb used to describe the accident
         • 'Contacted' Speed = 31.8mph, 'Smashed' Speed = 40.8mph

2. Techniques recommended in American interrogation manuals are often based on deception and psychological manipulation

   • Exaggerating the evidence against the suspect, Repeatedly challenging suspect's claims of innocence, Presenting suspect with scenarios of what the police think happened, Minimising the seriousness of the offence
   • The aim is to undermine the suspect's confidence in their memory, and alter their perception of the position they are in

3. Good Cop, Bad Cop

   • Police interviewers have different predispositions toward using particular tactics during interviews, and may prefer different tactics according to the weight of evidence and a person's previous convictions
     • A previous conviction increases the investigator's belief in the suspect's guilt and may prompt the interviewer to adopt a more accusatory interviewing style to increase the likelihood of obtaining a confession
   • Hakkanen et al. quizzed experienced violent crime investigators about the tactics they would employ in a homicide case
     • Balance of technical evidence vs 'soft' evidence (e.g., tip offs, rumours) influenced the use of different tactics: both human and dominant tactics were rated as more important for cases based on soft evidence
   • The interviewer's style has the potential to increase witness suggestibility, especially for child witnesses
     • During an interview, the interviewer can adopt a generally supportive style, or a non-supportive style
   • Research indicates that when children are interviewed in a supportive manner, they are far more resistant to misleading questions
     • Almerigogna et al. assessed 8-11 year old children's susceptibility to misleading post-event info
     • Children who were interviewed in a non-supportive style were sig more likely to offer incorrect answers to misleading questions
   • In a court of law, cross-examining lawyers are permitted to ask leading questions, despite the negative effects such questions are demonstrated to have on children's accuracy
     • Cross-examination by nature, adversarial, and lawyers thus ask confrontational, credibility-challenging questions that imply the child is lying
     • It is not surprising that children's testimony may be distorted, research shows they are just as likely to change correct, as incorrect, testimony