The investigation carried out by the Electronic Frontier Foundation found that the government program's use of automated computer algorithms threatens civil liberties:
The FBI's plans for automated tattoo recognition go beyond developing algorithms that can identify people by their tattoos. The experiments facilitated by NIST also focused on improving technology that can map connections between people with similarly themed tattoos or make inferences about people from their tattoos (e.g. political ideology, religious beliefs). On top of the free speech concerns, the project should raise red flags for religious liberty advocates, since many of the experiments involved sorting people and their tattoos based on Christian iconography.
"Importantly, tattoos are also speech, and any attempt to identify, profile, sort, or link people based on their ink raises significant First Amendment questions," the EFF said.