[mothered]

In a use of deadly force situation one is trained to shoot until the threat is neutralized. Deadly force is justifiable homicide if the person using deadly force reasonably believes there is an immediate threat of death or severe bodily harm to self or others.

Provided It's warranted, yes I agree.

In this case, where's the "deadly force?". A man who's In a wheelchair with no weapon used (nor found), and no direct or Indirect attack against the officers, Is no threat whatsoever.