Wrongful convictions have increasingly garnished media attention both in North America and Britain. In addition to a variety of factors, instances of false confession have been identified as a contributing cause of some wrongful convictions. As a result of this finding, social scientists have begun to study the interrogation process in an effort to understand the factors that may lead to such false confessions. The present article reviews what is known about the psychology of police interrogations, including an examination of the concept of investigative bias, the influence of potentially coercive interrogation techniques, and vulnerabilities of a suspect that can increase the likelihood of a false confession. The article also discusses a novel alternative approach to the interrogation process that has recently been implemented in Britain. Finally, the article proposes preliminary directions for "best practice" in the use of interrogation techniques.
Wrongful convictions have increasingly garnished media attention both in North America and Britain. Although it is generally believed that such instances are relatively rare, exonerations of convicted individuals through DNA testing are increasing at a rate that few in the criminal justice system might have speculated (Scheck, 2001). As discussed by Scheck, Neufeld, and Dwyer (2000), a variety of factors may be responsible for such wrongful convictions, including mistaken eyewitness identification (see Turtle, Lindsay, & Wells, this issue), use of "junk forensic science" that is not scientifically rigorous, prosecutorial misconduct, or ineffective defence counsel representation (see also, Westervelt & Humphrey, 2001). In addition, instances of false confession have been identified as a contributing factor in some wrongful convictions. Due in large part to such cases, social scientists have begun to explore factors that may lead a person to confess to a crime that he/she did not commit (see Gudjonsson, 2003; Kassin, 1997).
The incidence of false confessions in practice is, of course, difficult to assess. However, there exist a disturbing number of documented cases in which defendants confessed (and even were convicted and sentenced to death) but were later exonerated by irrefutable evidence. Leo and Ofshe (1998), for example, reviewed a sample of sixty cases of disputed confession in which a defendant's statement was the only substantive evidence linking him to the crime. Using rather stringent criteria, Leo and Ofshe classified 57% of these cases as "proven false confessions" such that the defendant's innocence was established by independent evidence (e.g., the actual perpetrator was identified through DNA testing), while 30% were classified as "highly probable false confessions" due to considerable evidence indicating that the defendant's statement was false. The remaining 13% of cases were classified as "probable false confessions" given that no significant evidence was present to support the defendant's guilt. Bedau and Radelet (1987) also examined 350 cases of wrongful conviction and observed that 14% (or 49 cases) involved documentation of "false" confession evidence. Similarly, of the first 70 cases of wrongful conviction identified in the United States through DNA testing, 21% (or 15 cases) included confession evidence that was later proven to be "false" (Scheck et al., 2000).
Although there are a number of factors that may contribute to a false confession, the interrogation techniques employed by policing agencies appear to account for a significant proportion of these instances. Clearly, interrogation of a suspect is one of the most difficult tasks in a police investigation. Historically, policing agencies have embraced interrogation practices that have been developed by a number of professional training agencies that are headed by former investigators, and have relied on the developers to ensure that the procedures are both effective and scientifically rigorous. …