From The Art and Popular Culture Encyclopedia
Civil death (Latin: civiliter mortuus) is a term that refers to the loss of all or almost all civil rights by a person due to a conviction for a felony or due to an act by the government of a country that results in the loss of civil rights. It is usually inflicted on persons convicted of crimes against the state or adults determined by a court to be legally incompetent because of mental disability.
In medieval Europe, felons lost all civil rights upon their conviction. This civil death often led to actual death, since anyone could kill and injure an ex-felon with impunity. In the old German empire, a person declared civilly dead was called "vogelfrei" ("free as a bird") and could even be killed since they were completely outside the law.
Historically outlawry, that is, declaring a person as an outlaw, was a common form of civil death.