Whoever wrote this needs to be educated in the two legal concepts known as Mistake of Fact, and Mistake of Law.  You can make a mistake of fact, you cannot make a mistake of law.

In the third example, the police were responding to a First Degree Assault.  Deadly Force is authorized to stop that sort of crime.  They arrived and found an armed man who would not drop his weapon.  This is why I teach my students in Use of Deadly Force, that if they have to call the police for an armed intruder, they had better have the weapon put down by the time the police come through the door.  If the dispatcher doesn't prompt you for this, YOU had better prompt the dispatcher.  Because if the police shoot, it is probably going to be adjudicated to be a mistake of fact.

In the second example, you can't always deploy non-lethal force in the time and space required.

The Liberal News Media trying to stir up caca again.

PS.  Let me unequivocally state that the shooting of the Minnesota woman was wrong.