Detectives are unique decision makers, who have to search for information, weight information and make an appropriate decision. There are four possible outcomes from a decision made by a detective; a true positive, a true negative, a false positive, and a false negative. A true positive is when the correct individual is charged, and a true negative is when an innocent individual is let go. A false positive is when a detective may charge the wrong individual. A false negative is when charges are dropped on a guilty individual. Although, these outcomes may be outside the control of many detectives; with the prosecutor fiscal (in Scotland) and the Crown Prosecution Service (in England and wales) having ultimate control over whether charges are dropped.
The implications of false negatives and false positives can be huge. For instance, if an innocent individual is incarcerated, then an innocent individual’s life is ruined and the real perpetrator is still free to pose a danger to society (Ramsey & Frank, 2007). In addition, if false negatives and false positives occur, then public perception surrounding the justice system may be damaged, which may reduce the deterrent effect of the penal system (Ramsey & Frank, 2007). For example, if citizens believe that they are unlikely to be charged for a crime, they may be more likely to commit such a crime in the future. It is important, therefore, that the decision making processes of detectives are studied.
Rationality versus Intuition
There are two main ways a decision maker can reach an outcome. One way is through being rational (Lee & Cummins, 2004). Rational decision makers use all the evidence available, weight it, integrate it and then make an appropriate decision (Gigerenzer, & Goldstein, 1996). Rationality, however, is halted in environments where there are time pressures, information is emotional, the decision making environment is ambiguous and when the information is complex (Bell, Mawn, & Poynor, 2013; Bright & Goodman-Delahunty, 2006; Cooper, Bennett, & Sukel, 1996; Tversky & Kahneman, 1974). Therefore, researchers, such as Snook and Cullen (2008) have suggested that it is not realistic to expect decision makers to be rational, and rather intuitive processes may be more likely. Consequently, the implications of intuitive decision making within detectives should be researched more.
When referring to intuition in this piece, I am referring to cognitive short-cuts called heuristics (Tversky & Kahneman, 1974). These heuristics are fast and frugal strategies that allow decision makers to use a limited amount of cues to navigate the environment around them (Gigerenzer & Goldstein, 1996). In that sense, intuitive processes are less complex, when compared with rational decision making models, such as Bayesian analysis (Gigerenzer & Goldstein, 1996). Simon (1956) proposed that the environment does not allow for fully rational processing to occur. Consequently, decision makers have a limited, yet efficient, cognitive system that allows them to make judgements in the noisy environment that surrounds them. The question this blog hopes to answer is, what implications can intuitive decision making have for decision makers within the police?
Detectives and Tunnel Vision.
The most widely cited irrational intuitive process relating to detective decision making is tunnel vision. Tunnel vision can be defined as a collection of heuristics and cognitive flaws that cause legal and forensic decision makers to centre on one suspect, and then search for guilt confirming information, and disregard disconfirming evidence (Martin, 2004). Findley and Scott (2006) suggest that tunnel vision is a negative decision making strategy employed by detectives.
Through investigating several case studies, Findley and Scott (2006) proposed that a common theme that seemed to arise in miscarriages of justice was the utilisation of tunnel vision. They suggest that tunnel vision, which may be accidental, can have an asymmetrical effect on officers’ search for, and interpretation of, information. For instance, an incorrect eyewitness identification could cause detectives to believe that a particular suspect is guilty (Findley & Scott, 2006). This may then effect how later evidence is perceived, with ‘neutral’ information being seen as guilt confirming (Findley & Scott, 2006). This conclusion has been supported by Ask, Reinhard and Marksteiner (2011) who found that individuals judged criminal evidence to be less credible when it disconfirmed a prior assumption of guilt. The more “elastic” the evidence was the more susceptible participants were to the negative evaluation of disconfirming evidence. For example, evidence such as eyewitness testimony is easier to stretch to fit prior beliefs in comparison to DNA evidence. Ask, Rebelius, and Granhag (2008), also, found that police trainees were susceptible to judging such ‘disconfirming’ evidence as more unreliable than consistent information.
Additionally, Findley and Scott (2006) suggest that the perception of guilt may then bias investigators into interrogating the suspect in a manner that may lead to a false confessions; that is, detectives may ask more leading and guilt directed questions. Hill, Memon and McGeorge (2008) found that a belief of guilt did lead to a self-fulfilling prophecy. In other words, interviewers who believed that the target individual was guilty, were more likely to ask guilt related questions, and thus prove to themselves that the person was guilty. Further, the self-fulfilling prophecy is a vicious cycle as a pre-decisional belief of guilt changes how individuals search for and evaluate information, thus causing prior beliefs to be reinforced.
Snook and Cullen (2008) suggest that the negative perception of tunnel vision is premature; heuristics may have positive implications for detectives. They argue that it is irrational to believe that police officers should investigate every potential suspect, evaluate all the evidence, and search all possible lines of enquiry. It is not heuristics that lead to negative outcomes, rather, erroneous information leads to such consequences (Snook and Cullen (2008). Heuristics may actually help detectives to navigate through a noisy crime scene and focus on relevant information, rather than all the information. Therefore, heuristics may decrease the cognitive load of detectives and fact finders, which may allow them to be more efficient decision makers.
In conclusion, fact finding and decision making in regards to policing happens in a complex environment, which may lead to intuitive processes occurring. However, the implications of these intuitive processes are still unknown. Some research suggests that intuitive processes are suboptimal and should be prevented, whereas alternative research proposes that heuristics evolved to allow us to make decisions in a complex environment. Ironically, it could be said that more information is needed. Future research should aim to highlight the implications that heuristics may have in detective decision making. My current research investigates heuristics and decision making strategies within a juror population, I look to see which variables promote accuracy, what causes cognitive fallacies and how individuals evaluate evidence. However, I do hope that for my post-doctoral research, that I can utilise my expertise in decision making and statistics and apply it to a policing context, and thus help to fill in some of the gaps I have highlighted in the literature.
Lee Curley is a PhD student at Edinburgh Napier University. Email: Lee.Curley@napier.ac.uk Twitter: @Psycurlogy