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Interview and interrogation methods and their effects on investigative outcomes

Additional Info

  • Authors: Christian Meissner, Allison Redlich, Sujeeta Bhatt, Susan Brandon
  • Published date: 2012-09-01
  • Coordinating group(s): Crime and Justice
  • Type of document: Title, Protocol, Review, User abstract
  • See the full review:

The interviewing and interrogation of suspects can be particularly important to securing convictions against the guilty and freeing the wrongly accused. There are two general methods of questioning suspects: information-gathering and accusatorial. The information-gathering approach, used in the United Kingdom, New Zealand, Australia, and elsewhere, as more generally in Western Europe, is characterized by rapport-building, truth-seeking, and active listening. The accusatorial approach, used primarily in the United States and Canada, is characterized by accusation, confrontation, psychological manipulation, and the disallowing of denials. Which method is more effective has become a hotly debated topic as the number of false confessions identified continues to rise.


Our objective was to systematically and comprehensively review published and non-published, experimental and observational studies on the effectiveness of interviewing and interrogation methods. We focus on the questioning of suspects using information-gathering and accusatorial methods seeking to elicit confessions.

Selection criteria

We conducted two separate meta-analyses. The first meta-analysis focused on observational or quasi-experimental field studies that assess the association between certain interrogation methods and elicitation of a confession statement. Field studies must have included: 1) at least one coded and quantified interviewing/interrogation method; and 2) data on confession outcomes tied to the questioning style. The second meta-analysis focused on experimental, laboratory-based studies in which ground truth is known (i.e., whether the confession is factually true or false). Experimental studies must have included: 1) a comparison of at least two distinct interviewing or interrogation styles (e.g., control method and accusatorial); and 2) sufficient data on either true and/or false confession outcomes. Both meta-analyses focus on the interrogation of “criminal” suspects. We note that whereas the aim of the accusatorial methods is to obtain confessions, the primary aim of information-gathering methods is to obtain information. Nevertheless, because of the importance placed on confessions in the extant literature and given the current focus on confessions in the analyses reviewed, our primary outcome measure was confession rather than the amount of information gained.

Search strategy

Several strategies were utilized to locate eligible studies: 1) keyword searches of more than 20 databases; 2) reviewing bibliographies of several relevant books and compendiums; 3) reviewing abstracts from recent conferences; and 4) requests of researchers and practitioners, individually and via listservs.

Data collection and analysis

We located 5 studies eligible for the field study meta-analysis and 12 studies eligible for the experimental study meta-analysis. We coded outcomes from both study types and report mean effect sizes with 95% confidence intervals. A random effects model was used for analysis of effect sizes. Moderator analyses were conducted when appropriate.

Authors’ conclusions

The available data support the effectiveness of an information-gathering style of interviewing suspects. Caution is warranted, however, due to the small number of independent samples available for the analysis of both field and experimental studies. Additional research, including the use of quasi-experimental field studies, appears warranted.

See the full review

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