Gun expert explains how Tex McIver could have accidentally shot his wife
Prosecutors say that Tex McIver must have meant to pull the trigger and shoot his wife Diane in the back. Why? Because it can take up to 12 pounds of finger pressure to pull the trigger of that gun. Watch as former Georgia Bureau of Investigation Special Agent Bert Davis uses two bags of flour to show "48 Hours"' Maureen Maher how it's possible to accidentally pull a trigger that requires that much finger pressure.