East Germany's secret police, the Stasi, were the most aggressive surveillance force of their day — at the Stasi's peak, one in 60 East Germans was snitching for the agency.
The tactics that the Stasi deployed to recruit informants — blackmail, cash, patriotism, immunity from prosecution, and gamification — are less interesting than the things the Stasi did to their adversaries, inflicting mental torture of various types to drive the opposition to attack itself, or simply give up.
Just by spreading rumors about the existence of informants, the Stasi were able to drive a wedge into the opposition, as activists turned their suspicions on one another.
But by forming circles of trust and mutual aid, demonstrating intergroup solidarity, and deploying active countermeasures, a resistance was able to form and, eventually, depose the hated, oppressive government and its army of spies.
The next stage was often to supplement covert surveillance with overt observation in order to communicate to the target that they were of interest to the Stasi and to create a sense of insecurity and paranoia. Tactics included questioning, repeated stop and searches, strange noises on telephone lines, conspicuous visits to the workplace so that bosses and colleagues were aware of the police interest etc.
The final stages entailed psychological and physical harassment: moving things around at home (one morning the alarm clock goes off at 5am instead of 7am, and the socks are in the wrong drawer, there's no coffee left…); damage to bikes and vehicles (eg slashing tyres); the spreading of rumours as mentioned above; ordering goods in subject's name etc.
Families were often used as leverage against activists at this stage – either as a method of blackmail (family members were sometimes subject to oppression as a way of putting indirect pressure on the activist), or persuasion ("your daughter will land in deep trouble if she remains involved in that group, can't you make her see sense? It's her career at stake…"). Physical harassment often included repeated arrests, physical attacks on the street (eg by plain clothes officers), or abuse and assault could be incited by the rumours that had been spread (eg bullying at work, avoidance by neighbours).
(via The Grugq)
(Image: Eavesdropping station, Racing Snake)