Why would a mentally unstable man have a machete in the first place? That’s scary enough all by itself. Eventually that guy was planning on using it in some way, and my guess is not in a good way. So he turned it against the Cops. Good riddance to bad rubbish. Glad the guy is dead, and I suspect his family is secretly relieved also. At least they know he won’t be coming after them now.
He certainly should not have had it. I think many people here really under estimate a mentally ill guy who is off his meds. Some of them tend to go totally bonkers. The majority, if they can be persuaded to take their meds, are ok. If they can't, then it is not likely to end well, especially if they have a weapon. I worked 11 years with nut cases like this. It was scary enough when they were NOT armed with a weapon. In this case, it was an all around BAD situation, and it might have been one of those situations where there were not going to be any winners.