Have you ever wondered how people remember a crime they witnessed or suffered? Did you know that human memory is susceptible to errors and distortions, which may compromise the veracity and validity of the evidence?
Memory-dependent criminal evidence is that which is based on information provided by victims, witnesses or suspects about a criminal act, especially through interviews (Hearings or testimonies of victims, witnesses and suspects) and recognition of people. It may be the only or the main evidence that a crime occurred and who was the perpetrator. Nevertheless, It can also be a fragile and unstable test, for it depends on the functioning of human memory.
Human memory is not an accurate and permanent recording of everything we experience. It is a dynamic and complex process, Composed of three stages: encoding, Information storage and retrieval. Each of these steps can be influenced by several factors.
During an event, The brain interprets and encodes the information perceived by the senses. Nevertheless, Human attention span is limited, which means that not all environmental stimuli are encoded. In addition, conditions such as stress, Witness distance and age can affect memory encoding quality. After encoding, Information is stored, but over time, memory may deteriorate and information may be forgotten.
During memory retrieval, The stored information is evoked. Nevertheless, human memory is malleable and susceptible to external influences. During conversations with other witnesses, police interviews or recognition of suspects, New information can be added to the event's original memory. This additional information can lead to false memories or mistaken acknowledgments.
Memory-dependent proof repeatability may pose a problem, because the quality of the original memory may decrease over time. The repetition of interviews with witnesses, especially without the use of proper protocols, increases the likelihood of permanent modifications to the original memory, resulting in loss and distortion of information. Likewise, The procedure of repeating the recognition of a suspect can generate greater familiarity with the face, leading the witness to have a greater conviction that the suspect is the true perpetrator, even if that's not true.
It is crucial that interviews and recognition of people are conducted by trained professionals, following scientifically validated protocols. Repeated interviews can bring more information, provided they are carried out properly. Nevertheless, in the current Brazilian legal context, The lack of scientific training of the actors of the justice system compromises the quality of the interviews. In addition, The time elapsed from the event to the memory retrieval also affects its quality, making post-event information more susceptible to distortion.