Tattoos are expressions of individuality, and getting inked typically communicates something unique about a person's experiences, personality, or beliefs.

It's no secret that law enforcement has long used tattoos to profile and identify criminal suspects. But more recently, the FBI teamed up with scientists at the National Institute for Standards and Technology (NIST) to create a system capable of identifying, grouping and making inferences about people based on their tattoos—something the EFF says raises serious First Amendment concerns.

One slide from an NIST presentation titled "Why Tattoos?" makes clear how law enforcement would use the system, which was developed alongside a group of third-party companies, universities, and private research institutions, to profile people en-masse. The slide explicitly states that tattoos "suggest affiliation to gangs, subcultures, religious or ritualistic beliefs, or political ideology" and "contain intelligence; messages, meaning and motivation."