But only rarely does body art play a pivotal role as evidence posited as proof of wrongdoing.

Prosecutors trying to convict former New England Patriot Aaron Hernandez in a pair of homicide cases could try to use the one-time football star's tattoos against him: They are seeking the artists who worked on Hernandez, saying they could be witnesses.

Criminal justice experts, however, say it's hard for law enforcement to determine whether someone with a tattoo linked to a kind of crime actually did the deed. As Todd Bettencourt, a tattoo artist in North Attleborough, Massachusetts — the town where Hernandez was living at the time of the killings — said, "some people just get it because it's cool."

Much of Hernandez's upper body is covered in tattoos: The open-mouthed face of a lion sits atop his right bicep, ringed by the words "It's about the fight in you;" ''1989," his birth year, spans the fingers of his left hand and a 10-word phrase favored by his father, "If it is to be it is up to me," runs down his left forearm.

It is Hernandez's right forearm that has piqued the interest of investigators, though they will not specify which design they have focused on.

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