If you’re asking about the unsub from Criminal Minds, it’s an unknown subject. That doesn’t actually exist in the FBI.
The term “unsub” is derived from “-unknown subject”—the term used by police to describe a perpetrator of a crime who has not yet been identified. This would never be used by agents at Quantico or the investigators on Criminal Minds because they identify suspects and don’t say that someone is unknown. Saying “subject with the unknown face” just sounds weird anyway since an agent can usually see their suspect’s face.
On Criminal Minds, an unsub is a ‘unknown subject,’ someone who the BAU hasn’t figured out yet. It’s not really used as a term in law enforcement so much because they’re often just using different terminology; typically they talk about perpetrators vs victims. The person doing the majority of perpetrating would be classified as the perpetrator and everyone else would be victims. A lot of cops are kind of reluctant to use words like victim or perpetrator because it seems clinical or dehumanizing – some say “bad guy” and “good guy”.
Unsub is short for “unknown subject,” and FBI agents would use this term as a kind of shorthand to refer to a criminal that they’re still investigating, or who has evaded their investigation. It’s used when you can’t identify the criminal in question.
An unsub is an unidentified person and a term used to describe them on Criminal Minds. Some episodes of the show have spawned books, DVDs, or video games that come with a copy of an unsub. Cases on the show have been inspired by real cases, but it is not known if the term was also taken from real life use. It’s not known what FBI agents call unknown people in their work, so this answer does not mention it.
No, it’s just a slang term.
An unsub is a person who ‘unsubscribes’ to the mental contact and profiles of one or more of our suspects by rejecting their offers. The unsub feels they can’t afford the time to stalk each profile, so they focus on only a few people who tend to do serial killings or abduct victims from specific geographical areas. This type of unsub is atypical. It’s easier for them because they don’t have to search through all types of cases and sorting out all the details; it’s also easier because we often give hints about what we’re looking for in a suspect like generic occupation, car make and model, physical appearance that might be easily changed with contact lenses
