In some countries, such as the United States, the law provides that the testimony of the victim or a witness is comparable to the murder weapon as evidence.a. But, Is the memory of witnesses a sufficiently objective and reliable key to resolve a case?
The weapon is a physical and tangible test from which very useful information can be obtained: who was its owner or who wielded it by the tracks on it. But the memory of the human being is not something objective and immutable. It doesn’t work like a camera, as several psychology research has shown. In fact, psychologist Elisabeth Loftus has proven throughout the 20th century that it is even possible to create false autobiographical memories in people’s minds.
Create false memories
Almost all of our personal memories are altered, disrupted by experience and learning. Our memory does not construct a fixed and detailed memory of a fact, on the contrary we only tend to remember something that we might call “the essence”. By remembering only the basics, we are able to relate the memories to new situations that somewhat resemble the original circumstances that evoked the memory.
Thus, the functioning of memory is one of the pillars that make learning possible, but also one of the causes of the vulnerability of our memories. Our memory is not perfect, and how many times we have checked without being surprised; it is fallible.
Long-term memory and memory recovery
It should be noted that our memories are stored in what we call long term memory. Whenever we reveal a memory in our daily life, we construct the memories with parts that we “carry” from there. The transition from long-term memory memories to the functioning, conscious system is called retrieval, and it comes at a cost: every time we remember something and then bring it back to the long-term store, memory is slightly altered by mixing with current experience and all its packaging.
In addition, people do not remember, rework, reconstruct the facts each time we verbalize them, always in a different way, always generating different versions of the same event. For example, recalling an anecdote among friends can provoke a debate about what clothes you were wearing 1 that day or what time exactly you got home, details that may end up changing when we bring the memory back. The details that we don’t pay attention to are usually not significant, but are essential in an essay.
The effect of emotions on memory
Situations of emotional stress also have a very powerful effect on the memory of witnesses and especially on the memory of victims. In these situations, the impact produces more or less permanent damage to memory. The consequences are in the extremely vivid memory of small details and a deep void on actions and circumstances which may be more important.
Peripheral memories are more likely than central memories when faced with a high emotional impact event. But above all, the emotions bathe and are imbued with the subjectivity of memories. Emotions make what hurt us seem much more negative, perverse, ugly, obscene or macabre than it objectively is; and in return, what is associated with a positive feeling for us seems more beautiful and ideal. For example, oddly enough, no one hates the first song they heard with their partner, even if it sounded on the radio or in a nightclub, because it has been associated with the feeling of love. But we must not lose sight of the fact that, for better or for worse, objectivity in a trial is a necessity.
Shocking damage, such as rape or a terrorist attack, can create post-traumatic stress disorder in a victim, cause intrusive memories for the victim and also blockages that prevent them from regaining their memory. And pressure from a prosecutor or police officer can create memories or testimonies that are not true. Imagine a paternalistic policeman telling you something like “I know it’s difficult, but you can do it, if you don’t confirm it to us, this man will be free and content at home.” An insidious policeman or prosecutor, who puts too much pressure to get answers, will bring out a false memory. Only when the victim is able to de facto emotionally distance himself and minimize his importance will he (perhaps) be able to regain his memory.
Trust in memories …
One technique for avoiding post-traumatic stress and blocking is to understand or explain to someone the facts as soon as they occur. Outsourcing memory in a narrative way allows it to make sense.
When it comes to witnesses, there are always more plausible memories than others. It is never wrong for a forensic expert to assess the value of the case before allowing him to testify at trial. The optimal level that we remember occurs when our physiological activation is medium; nor so high that we are in a state of anxiety and stress as can occur during an exam; not so low that we are in a state of relaxation which slows down sleep. In this case, a crime causes a strong physiological activation, an emotional stress that is associated with the event and therefore occurs every time we try to remember, which decreases the quality of the record.
Therefore, the memory of a witness will always be more useful than that of the victim by being subjected to less emotional activation. It should be noted, out of curiosity, that the most likely memory of a victim is one that focuses on the object of the violence, that is, the weapon.
Bias in legal proceedings
On the other hand, we have to keep in mind that sometimes reconnaissance wheels and interrogations may be unintentionally biased. This is because this bias exists towards injustice, or by ignorance of the effect it has of formulating a question in a certain way or of concretely ordering a set of photographs. We cannot forget that the police are human beings and have as great an aversion to crime as that of the victim, so their aim is to put the culprit behind bars as quickly as possible; they falsely think that if the victim or the witness says that one of the suspects looks like the culprit, it is because it must be him and that they cannot release him.
There is also this bias in the population which dictates that “if someone is suspicious, he will have done something”, then there is a widespread tendency to believe that suspects and accused are blindly guilty. For this reason, when faced with a series of photographs, witnesses often tend to think that if they present them to these subjects it is because one of them must be the culprit, whereas it is sometimes random individuals and one or two people slightly match certain characteristics with those described to them (which in fact don’t even have to be true). This mixture of prejudices on the part of the police, the prosecutor, the judge, the jury, witnesses and the general public can result in such a combination that an innocent person is convicted, a reality that sometimes happens.
Of course, I don’t mean to say that no testimony should be valued, but it should always be done by evaluating its veracity and reliability. It should be borne in mind that the human mind is often wrong and that we must emotionally distance ourselves from suspects before judging them in order to do so objectively, witnessing not only reliable witnesses but also rigorous evidence.