I don't live there, but the principle is the same, anywhere. If I employ an ISP to provide a service for which I pay, their responsibilities are to me, not to someone else who doesn't pay them.
An ISP is not a properly constituted law enforcement body with legislated authority to do police work. There do not appear to be any checks and balances to ensure justice takes place, as is a common law right and a legal requirement. For an ISP to actively monitor individual usage would seem a violation of existing privacy legislation.
I hope someone sues them and brings criminal charges against them. If the ISPs had any sense, and guts, they should see the legal minefield they are agreeing to and mount a group challenge in court concerning the legality of what is being enacted.