[Griff]

It changed with digitalization (?) of communications. Old phone tapping required an agent on the line listening as they didn't have an efficient way to collect and store the analog information. Folks who support easy collection of data argue that it became much harder to follow the bad guys when mobile devices came on line. I'd argue just the opposite, they've gone from a small focused surveillance system to an enormous one with much more capacity using the excuse of difficulty to make their work much much easier than it was for the guy tapping in by hand.