Do you support stand your ground laws in Australia?
This is the case in the USA where if someone comes into your home you may use your baseball bat or gun to get them out, or to kill.
In Australia they expect you to call the cops and ask the crook to sit down and patiently wait for their arrival. Given this won't happen the police will simply show up, ask you a few useless questions (because the perp is gone!) and then not chase up on it.