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Failures in Criminal Investigation

NCJ Number
Police Chief Volume: 76 Issue: 10 Dated: October 2009 Pages: 54-56,58,60-62,64,66
D. Kim Rossmo
Date Published
October 2009
9 pages
This article identifies "cognitive biases," "organizational traps," and "probability errors" that lead to failures in criminal investigations, i.e. the failure to prosecute the guilty person or the mistaken prosecution of an innocent person.
"Cognitive biases" that can lead to failed criminal investigations include the biased beliefs and memory limitations of eyewitnesses to the crime being investigated; investigators' reliance on their intuition rather than reliable and adequate data that are carefully and logically analyzed; investigators' use of simplistic "rules of thumb" that ignore the complexities and alternative scenarios presented by case evidence; and the related cognitive bias of "tunnel vision," which focuses narrowly on a limited range of possibilities regarding the features of and suspects in a case. "Organizational traps" that can lead to failed investigations pertain to characteristics of the structure and dynamics of the law enforcement agency pursuing an investigation. Organizations tend to promote uniformity and standardization that resists change and creativity, which can restrict investigators' options and behaviors in pursuing and analyzing evidence. Organizations also are reluctant to acknowledge mistakes and change course in major investigations that receive media attention. "Probability errors" that lead to failed investigations pertain to flawed assessments of the likelihood that a set of events is due to a particular set of causes. Related probability errors are the failure to consider coincidence in assessing links among events and computation mistakes that underestimate or overestimate the likelihood that two or more events would be connected. If all of the aforementioned factors in failed investigations are to be acknowledged and addressed, law enforcement agencies and their investigative personnel must be trained to recognize the various factors that can undermine or misdirect an investigation. Organizational checks and balances must also be devised to ensure that investigations are carefully scrutinized for flaws and oversights. 1 figure and 15 notes