To See or Not to See: What Makes a Good Witness?
A witness might be someone who saw a crime being committed, a victim themselves, a police officer who made an arrest and conducted the interview of the suspect, or even a forensic practitioner who attended the crime scene. All are classed as a witness in a British court of law.
But when we, the police, talk about a witness, we are almost invariably talking about a member of the public who can tell us what happened at a given moment in time; someone who saw or heard something that we are interested in and which assists us in establishing what took place.
The police will then ask the witness to recall, from memory, what happened. Our brains are wired in a certain way and we use 'recall memory' to assist us in avoiding risks that we have already come across in the past. This recall is linked with instincts and mechanisms in order to remember how an event happened, so that we can learn from it to avoid the same risk in future. The police will access a person's memory in what is known as a cognitive recall system, to establish what a witness saw. Sometimes they are asked to recall an event that has literally just taken place, while others are asked to remember things that happened weeks, months or even years previously.
The problem is that, because of the way our brains store and use information, when we witness an event, our evidence is tainted by our perceptions of what we've seen there and then, and also previously - and the emotions we feel. People are not CCTV systems and as a result, no two people see the same incident in exactly the same way.
Which is the better witness?
For example, Witness A and Witness B are standing side-by-side in the street. They both see the same incident. Let's assume that incident is a man getting out of a car and stabbing another man in the street and then driving off. You'd think that both onlookers would be able to give you very similar accounts of the event, give or take some variations due to differences in their sight and hearing ability?
What if I told you that Witness A saw violent angry looks on their faces, lots of blood, heard a quarrel over the custody of children and could describe in detail the exact shouts and screams for help coming from the victim. On the other hand, Witness B could describe the two men's appearances and what they were wearing, but heard nothing during the entire incident? Which one of these two witnesses has provided the better quality account?
It turned out that Witness A had once experienced an incident as a child in which his mother had been stabbed in the street, which meant he had an emotional attachment to viewing this new incident. Most of his description upon recalling the new incident, related to his brain linking with his previous experiences. He had focussed heavily on the victim and didn't necessarily see what had taken place as he was replaying what might have happened to his mother. And then, when he recalled what he thought he had seen, it was clouded by feelings and emotions that had nothing to do with the actual event in front of him.
It turned out that Witness B had previously been a soldier and was used to dealing with stressful situations whilst observing and collecting information. The soldier had no emotional connection to the event and disputed the fact that there had been a quarrel or large amounts of blood. The soldier's descriptions of the suspect's appearance and his clothing led to a conviction.
You can now begin to understand that Witness A and B have very different perceptions of what happened, especially when asked to recall it at a much later date - perhaps several days after the event. It's not unusual for some witnesses to add in shouting and actions which didn't actually take place, completely unintentionally, due to their past experiences or emotional connections to the incident.
Interviewing witnesses and helping them sort through their memory is extremely difficult sometimes. A good police interviewer is worth their weight in gold - and this is where experience comes to the fore.
Physical descriptions of people are extremely important, regardless of whether the police know who the suspect is or not. Many witnesses will only recall the clothing a person was wearing. They won't pay any attention to facial features, hair colour, eye colour. And witnesses always describe someone in relation to their own viewpoint:
'He was very tall and thin and was wearing a red jumper,' is very typical of the type of description a witness will first give. But the description is purely relative to themselves. Another police officer who is tall and skinny himself could walk straight past this suspect in the street as he has imagined that he is looking for someone who is taller and thinner than himself.
How can you be a good witness?
Independence from the event in every way is the perfect start, although this is not always possible because, whether we like it or not, we are all influenced by our previous experiences.
Volunteering to be interviewed as close as possible to the actual event is the goal. Lots of witnesses say things like 'I'm away for two weeks on holiday - I'll speak to you when I get back,' - the longer you leave it, the more difficult it is to produce an accurate account.
3. Have your day in court
And, going right back to where I started this, a witness is only good if they are prepared to give evidence in court. A great many witnesses refuse, and whilst they may be compelled legally to attend court and give evidence - hostile witnesses who change their mind and refuse to assist can severely damage any case. So be prepared and get comfortable with the idea of going to court, should you be required to do so.
All these things will make you the perfect witness.
David Videcette is a former Scotland Yard investigator with twenty years' experience of hunting down criminals and the author of The Theseus Paradox. Find out more about David and his work at www.davidvidecette.com
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