First up, he said, are palm prints. The FBI has already begun collecting images and hopes to soon use these as an additional means of making identifications. Countries that are already using such images find 20 percent of their positive matches come from latent palm prints left at crime scenes, the FBI's Bush said.
You don't have to be a criminal or a terrorist to be checked against the database. More than 55 percent of the checks the FBI runs involve criminal background checks for people applying for sensitive jobs in government or jobs working with vulnerable people such as children and the elderly, according to the FBI.
The ACLU's Steinhardt doesn't believe it will stop there.
"This had started out being a program to track or identify criminals," he said. "Now we're talking about large swaths of the population -- workers, volunteers in youth programs. Eventually, it's going to be everybody."