Off duty cop rams suspect vehicle

"If you were just a good Samaritan following this person, I don't think you'd be indicted," he said. "I think the shotgun trumps everything."

The teen with the shotgun was thrown from vehicle, and died after being rammed,

Geoffrey Alpert, a criminologist at the University of South Carolina, said the issue becomes muddied because the younger sibling fired the shotgun.

I'd say since the teen used a deadly weapon, the officers response was correct

Use of Force New study on Use of Force

While the rules on use of force are different for civilians, it may pay to follow these cases, as your knowledge at the time is what you'll bring to court.