It reads almost as if he (Daniel Mendoza) shot her because he was annoyed with her. And I have no doubt that she was being annoying. People who have been going without sleep and are hyped up on drugs are annoying. Throw in what ever other mental problems she may have had and they become down right exasperating.
But you are not allowed to kill them for that.
I got the impression from the article that this ended in an unnecessary death because of a series of errors and misapprehensions. Knowing his daughter was having mental problems including an obsession that some ex-boyfriend was stalking her, the woman’s father bought her a gun and taught her how to use it. Some cops arrived at the scene know the woman was having a psychotic episode and was armed. Another incorrectly thought he was pointing a gun at him and blazed away at her with a 9mm but missed. Other cops heard those shots and thought she was firing at them. She lay down in the hallway, then, thinking her ex-husband had arrived, turned 90 degrees and was reaching for something. Mendoza panicked, assumed she is going for a gun, and took out the “threat”. The cops all clam up, because at least several of them contributed to a royal screw-up, and whoever was in command failed to control and coordinate his forces.
Some lessons: 1) Don’t arm your paranoid schizo drugged up children. 2) Police frequently are not good at dealing with people having mental crises, because they expect somewhat rational behavior, like following commands, staying still more than ten seconds, etc.; unfortunately, nuts act nutty. 3) Unfortunately, good tools do not exist for dealing with armed, violent, or potentially violent nuts.