Cops have stricter requirements for lethal force than Citizens do.Tasers don't always work, this guy wasn't acting rationally which potentially could mean he's high, which would also cause a taser to not work.
When faced with a possible lethal threat a taser is not a good option.
If someone is trying to break in your house and possibly has a gun are you going for your pepper spray?!
Heck no, your spraying lead.
Cops do have multiple options, but so does the bad guy. He chose wrong.
I don't have backup at my house.
As I said before there were two officers. Why didn't one use a Taser?