Don't Get A Tattoo

     This isn't an issue about possible infections or even whether or not you should be defacing your body, but from the perspective of operational security; specifically, the fact that tattoos are distinguishing marks that can be used to identify you or provide other information about you. Below is a screenshot from a Vox.com story discussing how a personal trainer was fired for having attended the Charlottesville rally after he was identified due to his distinctive tattoo. And here is a news report of a robber that was identified due to his distinctive face tattooing.

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       Of course, the risk isn't just an irate customer or boss, but the government (particularly the FBI) has been funding work into developing tattoo databases (see this 2012 article, and this 2015 article) for automated searches. As of last year, such systems had very low accuracy rates. In an article by Captain Sean T. Stewart of the Pima County Sheriff’s Department, he discusses why correctional institutions should be photographing the tattoos of their detainees, and how tattoos can be used for various purposes including identifying gang affiliations. He also describes an actual incident where he included in an alert about an escaped prisoner not only mug shots, but photographs of the fugative's tattoos. These photographs were later key to the escapee's identification and apprehension.

       There are also the broader implications of Big Data. In a 2016 post, blogger "Justin" at Your Ultimate Security wrote:

Tattoo recognition is invasive for two reasons.  You can be identified through your tattoos, in much the same way as facial recognition. This requires that your adversary has a sample for comparison, but this is not outside the realm of possibility or even probability.  Most people have photos of their tattoos on social media.  If you have been in the military recently your tattoos have probably been recorded in promotion photographs.  If you have been arrested, there is a decent chance your tattoos were photographed. Once your identification is made, you can be tracked through an airport or shopping mall or positively identified on social media – even if your face is not visible.  The other, more alarming risk of tattoo recognition is the inferences that can be drawn from your tattoos.  The NIST TATT-C program attempted to draw conclusions from an individual’s tattoos including political alignment and religious affiliation. To me this seems to be a fertile breeding ground for false positives.

His recommendation was to not get a tattoo in the first instance, but if you decide to do so, locate it where it isn't going to be plainly visible and avoid posting pictures of your tattoo on social media.