Witnesses are unreliable in criminal cases for a multitude of reasons. They could be biased, they could be surprised by the event or they could be too far away to see clearly — just to name a few reasons. Witness testimony is often questionable, even when the witness feels strongly that what they are saying is true.
One reason for this lack of reliability is known as “weapon focus” or the “weapon focus effect.” In brief, it means that a person focuses only on the weapon being used at the scene of the crime. They don’t spend nearly as much time or attention on other details. In fact, a certain law professor once claimed that people focus so strictly on the weapon that they exclude everything else.
Say that the crime committed is the robbery of a coffee shop. The person committing the robbery walks in, pulls out a gun and takes the money. They leave the premises. Afterward, the person behind the counter, at whom the gun was pointed, can remember the color of the gun, the size of it and maybe even the make and model — but they can barely tell the police anything about the suspect’s identity. They may not even remember obvious details like skin color or hair color. They could absolutely get things like height or weight wrong.
If you get accused of a crime, you have to consider the reliability of the witness. They may believe they know what they saw, but do they? Make sure you understand what legal defense options you have.
