In crimes involving a weapon, the testimony of witnesses may be compromised. The issue is something experts refer to as “weapon focus.” It can make it so that the things witnesses remember are not accurate or that they cannot recall details about the suspect in the crime that you would otherwise expect them to remember.

In repeated studies, researchers have found that memories are worse when weapons are involved. Witnesses make mistakes. They pick the wrong people out of lineups. They accuse people with only a passing resemblance to the actual perpetrator of the crime. They forget the details. They leave things out.

Why does it happen? As the name of the phenomenon implies, the witness focuses on the weapon — like a handgun or a knife. They’re afraid. They watch the weapon in an instinctive move to protect themselves. They hardly look at the person who is holding the weapon.

In nonweapon cases, they may remember things like whether or not the person had tattoos, what their hair color was, hold old they looked or their skin color. In weapon cases, they may not have any idea about these common details. When given a choice between two people, they won’t be able to accurately identify which person they were looking at, even during an extended encounter.

This causes all sorts of issues in cases, from false identifications to shaky witness testimonies that should not stand. Those who find themselves facing charges and believe that the testimonies against them may be compromised need to know exactly what legal defense options they have and how they can protect themselves from an inaccurate witness.