Memory is often treated as a solid piece of evidence–something that stays fixed once an event happens. However, psychologists know that memory is malleable. It is constantly reshaped by emotions and information we’re exposed to afterward. In the world of crime, this flexibility becomes a major risk, because what people think they remember holds significant influence in investigations and verdicts.
During a crime, the brain is under intense stress. High arousal narrows attention disrupts perception, limiting what gets encoded in the brain. Instead of storing a complete picture, the mind captures fragments. Afterward, the brain tries to reconstruct meaning, filling in gaps with assumptions or prior experiences. This reconstruction feels natural and accurate, but it’s already a blend of real detail and mental inference.
Where memory becomes truly malleable is after the event. Once investigators, friends, media, or even casual conversation introduce new information, the brain can merge these details into the original memory. For example, a witness who heard others talk about a tall suspect, may later recall the suspect as tall, even if they never saw the person clearly.
Interviews and interrogations can unintentionally shape memories even more. Leading questions and repeated questioning can alter how someone mentally revisits the event. Pressure also plays a pivotal role in this phenomenon. Over time, small shifts add up, and the memory can be reconstructed differently from the original experience.
This malleability becomes dangerous in courtrooms. Eyewitness testimony is often powerful, especially when witnesses express confidence. This is why it is important to recognize that confidence does not reliably indicate accuracy. A witness may be certain about a detail that was actually introduced later, or confidently describe a face they misremembered under stress. Yet jurors tend to trust vivid, assertive recollections.
Recognizing the malleability of memory doesn’t mean disregarding witnesses. It means creating systems that protect them from distortion. Avoiding suggestive interview techniques, recording all questioning, and educating jurors about how memory actually works, are crucial to ensuring fair trials.
In criminal cases, the truth shouldn’t depend on someone’s memories but rather concrete evidence. Understanding memory’s malleability helps ensure that justice is guided by objectivity.