The manual of WITSEC, the U.S. Marshals agency that oversees the Witness Protection Program, describes three stages of agency involvement.

The Red Zone—when a subject is held in protective custody, while in prison or on trial.

The Green Zone—when that subject, along with his or her family, has been placed in a new identity and location and is living securely in that identity, known only to his WITSEC case agent.

And the Blue Zone—the state most feared, when there is suspicion that a subject’s new identity has been penetrated or blown. When he or she is unaccounted for, is out of contact with the case agent, or has fled the safety of the program. When there is no official knowledge of whether that person is dead or alive.