Tattoos have a long history and have over the millennia been signs of different social classes, from royalty to the rags. In more recent times, they have become associated with criminals, sailors, and criminal sailors (a.k.a. pirates). In fiction, a tattoo can act as a shorthand for "criminal", and at times it's not that far off. Organized crime from Yakuza to Gangbangers have their own codes, and prisoners tell their life stories in pictures.
The attitudes towards tattoos have softened during the past decades. In an old movie, a character with a tattoo was either a sailor or a thug. In the 2020s, regular middle-class people get tattoos. Indeed, old pirate and prisoner tattoo designs have been adopted into the general lexicon of regular tattoos, prime example being the spider web, which depending on the bearer might have once meant drug addiction, incarceration, or killing a minority, but is now a fashion accessory.
Still, the stigma with the past backgrounds makes tattoos popular with rebel types. Even the Rule-Abiding Rebel — or especially the Rule-Abiding Rebel, since it does not actually require committing illegal acts to look rebellious. There is still extreme stigma related to tattoos in Japan, as they are still closely associated with the Yakuza to this day. A tattoo is still a common visual cue in Japanese media for a character of dubious morals or simply a delinquent.
This could be regarded as an Evolving Trope; as tattoos went into mainstream fashion during The '90s, the gangland crooks took their tattoos up a notch with neck tattoos and face tattoos (see Tattoo as Character Type). If a group of crooks has a defining tattoo, see Group-Identifying Feature.
May be Embarrassing Tattoo when a crook or rebellious punk rock musician goes straight and moves to Suburbia. In futuristic settings, a Barcode Tattoo may be an Orwellian surveillance and control tactic.
In Real Life in the 2020s, tattoos have gone mainstream. Suburban soccer moms and accountants get tattoos, and the college student barista at your Bourgeois Bohemian coffeshop has a full sleeve tattoo that you'd only have seen in The '80s on a Heavy Metal lead singer or a Badass Biker. Some Real Life tattoos have a horrifying usage. Nazis put identification tattoos on Jewish prisoners in WWII concentration camps during the Holocaust.