This is why I included the bit about direct observation. Before dragnet surveillance, you would need to travel near someone who had an active interest in you specifically in order for your location to be marked down. With a dragnet surveillance system every movement you make can be used to unmask your whereabouts after the fact, regardless of whether anyone observed it at the time.
I think we agree then. the classic distinction between public and private space is almost a red herring in this argument. the focus should be on how long are you allowed to store information, or maybe even how widely and indiscriminately are you allowed to collect it in the first place.
