Fingerprinting
Fingerprinting is an extremely useful technology. Fingerprints are unique to each person, so it makes someone easily identifiable. The FBI already has millions of fingerprints. People who get arrested get theirs taken, but there are also four states in the US that require fingerprinting to get a driver's license. In order to work with children or other vulnerable populations, you need to get fingerprinted. This information goes into the FBI database where it stays forever.