You get accused of a crime and arrested. The reason that the case against you looks so strong is because an eyewitness comes forward and says that they remember you being at the scene of the crime and playing a role in that event.
An eyewitness tends to carry a lot of weight in a court case. Even if you contradict their statements, the jury assumes that you have a reason to mislead them -- trying to get out of the charges -- and the eyewitness does not. They trust that witness and their memory.
But should they? Studies have found that memories are not reliable and eyewitnesses are often wrong, whether they know it or not. Part of the issue is that recalling memories tends to distort them. The brain changes them slightly, perhaps based on new information or outside influences.
"A memory is not simply an image produced by time traveling back to the original event—it can be an image that is somewhat distorted because of the prior times you remembered it," said one researcher. "Your memory of an event can grow less precise even to the point of being totally false with each retrieval."
That's a strong statement. What if the eyewitness's memory is "totally false" and that's the actual reason that you're contradicting their statements? Is the jury going to believe you or the witness? If you get convicted based on their testimony and their false memories, is that really a fair and just outcome to your case? Make sure you understand all of your legal defense options at a time like this.