The NGI is meant to eventually replace the existing IAFIS system, but there's much more to it than that. New features like Rap Back essentially provide notifications when people in "positions of trust" like bank tellers and teachers break the law so whatever authorities they hold might be upheld or revoked. And then we've got the Interstate Photo System, a tool that allows law enforcement to search for photos "associated with criminal identities" -- sounds like a useful enough tool, but privacy advocates are a little uneasy for a whole host of reasons.

Take the very origin of those images: you can expect your mugshot to be in there, but if you apply for a job that requires your fingerprints or some sort of background check, you may need to submit a photo that could wind up in the NGI. There's a big question about accuracy, too: the NGI will return a ranked list of candidates for a facial search, but the Bureau says "the candidate will be returned in the top 50 candidates" 85 percent of the time if the perp is actually in the list at all. What happens if that list doesn't actually contain the right person? No one's entirely sure, and that's a little worrisome.