While your technical definition is correct, its actual usage is not.
First, all death investigations where one individual kills another are investigated as a homicide.
Second, ever hear of the term "justifiable homicide"? I mentioned it in my original post, did you look it up?
.
justifiable homicide:
"the killing of a person in circumstances that allow the act to be regarded in law as without criminal guilt."
.
Notice that this definition is quite contrary.