How we change what others think, feel, believe and do
Interrogation is an asymmetrical form of dialogue, such that that the goals and methods used by one side are different from those used by the other side.
The interrogator seeks to acquire information from the respondent that is needed for some purpose, such as action to discover 'who did it'. The goal of the respondent is to achieve his or her own interests, significantly including self protection and possibly to achieve wider social goals (particularly if they are a witness or are innocent).
There are three types of interrogation:
In criminal or military interrogation, the questioner is often an officer of some kind who is trained in many interrogation techniques. The person being questioned may be a suspect or a witness, and techniques used may thus vary quite significantly.
A military interrogator causes complete emotional collapse of a captive suspected of terrorism, who then reveals names, dates and targets.
A police officer questions a witness at the scene of an accident.
A parent questions a child about what happened at the party last night.
Whilst interrogation is not directly about persuasion, it includes many persuasive elements. The main goals of interrogation are usually acquisition of information and the most significant persuasion in this is to get the other person to collaborate.
Because the respondent may well be motivated to not to reveal all or tell other than the truth, the interrogator may need to use various tricks to achieve their goals.
A significant trap in interrogations is that the person being questioned will give answers simply to get away from the interrogator or otherwise otherwise give false information about what is being sought (such as a witness 'being helpful'). It is thus important for the interrogator not to take simple answers at face value, but to find ways of corroborating them, for example by asking related questions at a later date or checking up on what they are told. If evidence is to stand up in open court, it must be virtually bulletproof.
The process of interrogation is often constrained by law in some way. In particular if police use excessive pressure on a suspect, then in court any confession or evidence may be considered unsafe.