Might I inquire just how many manic individuals that are in a psychotic state you have dealt with as a law enforcement officer?
Over the past 30 years I have handled a number of them and only a great deal of luck and the grace of God I have not had to use deadly force. It is a split second decision that can go one way or another. This particular time deadly force was used. It will be reviewed over and over in both civil and criminal settings with all of the hand wringing saying, "He/she could have done xyz." The post shooting investigation will be hundreds of pages, if not thousands of pages, long. The civil depositions will be hundreds of pages in length.
Since they don't provide you with any crime scene photos, shooting diagrams, autopsy reports, witness statements, the shooting officer's statement, just what are you basing your opinion on?
Get some "Force on Force" training where you actually deal with situations like this and see if you would have shot.
I will admit that I don't know if the officer should have used deadly force. I can't make that determination based on a ten paragraph news article. Do some research at
http://www.forcescience.org" onclick="window.open(this.href);return false; and you may learn you don't know what you don't know.