Social death is the condition under which some people can be condemned to civil death, while the rest of us fail to care or even to notice. It is the condition under which entire groups of people may be exposed to disproportionate state violence, neglect, and/or exploitation, without provoking the concern or support of other members of the community.
Social death is both a condition of civil death and one of its effects; they amplify one another in a vicious circle that is difficult to interrupt. Together, civil death and social death name the position of those whose status is always already perceived as criminal and labelled as a “security threat.”'
From Lisa Guenther's blog on the California prison hunger strikes.