This is a very good question.
Despite the potency of confession evidence in criminal law, recent DNA exonerations indicate that false confessions are a contributing factor in numerous wrongful convictions. After distinguishing between voluntary, compliant, and internalized false confessions, this article reviews research implicating a sequence of three processes responsible for false confessions and the adverse consequences of these confessions. First, police often target innocent people for interrogation because of erroneous judgments of truth and deception made during preinterrogation interviews. Second, innocent people are sometimes induced to confess as a function of certain police interrogation tactics, dispositional suspect vulnerabilities, and naive mental state that accompanies innocence. Third, people cannot readily distinguish between true and false confessions and often fail to discount those confessions they perceive to be coerced. At present, researchers are seeking ways to improve the accuracy of confession evidence and its evaluation in the courtroom.
It is believed that the main psychological conditions under which confession wil occur have been outlined here. These conditions, none of which is deemed suicient and all of which are deemed necessary, and all of which are in the person's cognitive field, are: 1) The person is accused by authority or its representation. 2) Evidence is presented (or is believed available). 3) Forces friendly to the accused are reduced. 4) The person feels guilt. 5) The person perceives that confession is the path to psychological freedom