I'm going to take a step back for two seconds to remind everyone that “subscriber information” is defined in the bill as name, address and those sorts of things.
If police get information back that is nonsensical.... They would be doing that investigative step once they receive the information. If Joe Schmo doesn't exist, I suppose they would follow up, but otherwise.... I can't conjure up a scenario any better than that to answer your question, really.
Police who work in that space may be able to respond to your question better than I can.