Democracy is rule by the result of a popularity contest, and no government wants to be caught having the charge of "not protecting the people" leveled against them because that makes them unpopular. Not the current government, and not the next one either.
In a year and a half when the election is in full-swing someone will ask Justin if he will repeal it. He'll avoid the question (probably), and even if he agrees to it, he'll renege once he is elected. Why? Because it's good for him to have it in place, and the existing government will be painted with the brush of unpopularity for introducing it.
As you've stated, what is needed is oversight. But sadly while we live in a democracy every government we elect will want to monitor and track us, while pretending that they mostly don't. Because arresting people before they do something is popular. And appearing reactionary after the fact is unpopular. That's the nature of the beast.