Mleake, You are correct and I should have addressed that point in my earlier post. Protection of oneself or a third party from the use or threat of use of a deadly weapon.
In N.C. an officer can use deadly force against a person who is making his escape by use of a deadly weapon. This is based on the assumption that the perp is a continued danger and is actively using a weapon.
The NC department of corrections can fire on an unarmed convicted felon to prevent escape. A pretrial detainee(person in jail) cannot be shot to prevent his escape unless he is using a weapon as a means of escape.