Fingerprintable

It appears, under the Leandre C. rationale, a youth could be printed for investigatory police purposes prior to an arrest, but might not be eligible for fingerprinting upon arrest because the charge is not a fingerprintable offense.

Source: wiktionary

Many are silent upon connection until you send them the expected string, but some will actually prompt you for a login in identifiable and fingerprintable ways.

Source: wiktionary