Decision Making Theory and its Implications for Policing

Lee Curley

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: Twitter: @Psycurlogy

7 thoughts on “Decision Making Theory and its Implications for Policing

  1. Thank you for the article.
    I appreciate that it is fairly short and thus it is difficult to go into the contradictions, paradoxes, opposing perceptions and shades of grey which beset policing.
    Decisions seem to be treated as binary and value-free, ie ‘right’ or ‘wrong’ at the point of charge. I’m not clear how this would apply to, for example, to a defendant who:
    – is charged but not convicted
    – there is insufficient evidence to charge or is found not guilty at a criminal standard of proof, but is found to be liable in a civil court on balance of probabilities,
    – is found guilty, but believes this to be unjust, eg they believe their actions to have been reasonable but the court takes a different view.
    In many cases, it is impossible to say in any absolute sense, whether a decision to charge is right or wrong.
    I suppose my question is: – is the decision making theory too simplistic to be applied to the vagaries of real life?

    • Hi Robert,

      Thank you for your question it is much appreciated. I would say, currently, yes. Decision making literature has focussed to much on binary outcomes and simplistic decision making processes. Currently, my colleagues and I at Edinburgh Napier University are hoping to rectify this. We are investigating the decision making processes behind jurors in the Scottish legal system, where three verdicts are available. Further, I would say decision making theory can be applied to a policing context, but I do agree that research needs to extend beyond simplistic binary outcomes. I hope this answers your question.

  2. Lee, thank you for introducing this topic here. This is an area that I have previously published on and am currently researching in the context of intelligence practice. As Robert says in his reply, it is difficult to cover off all the challenges, paradoxes and so on that usually are features of the dynamic. In the research I read, I am beginning to see that policing decisions are being viewed through the VUCA lens (a business model that highlights the volatility, uncertainty, complexity, and ambiguity facing decision-makers), which is a development I very much welcome – have you studied that? Heuristics have value but I believe that, individually, the circumstances in which they emerge are significant. Is the heuristic solely the product of pragmatic policing practice – potentially reinforcing traditional ways of thinking and working and contributing to the kind of tunnel vision you describe – or (even if it has its roots in practice) is it informed by scholarship and/ or research? It seems to me that the latter type are more, objective, credible and legitimate. There is some great research out there. Your reference Kahneman; his book Thinking Fast and Slow should be at the top of any reading list on this subject. Gary Klein’s work on naturalistic decision making should also be on that list. Recently, my research on the use of simulations to train problem-solving and decision-making took me to Oslo where I met with Ivar Fahsing who is a senior cop in the Norwegian Police University. His thesis ‘The Making of the Expert Detective’ is insightful and motivating – suggesting that real progress can be made in this field if (a) decision-making is better recognised as a core policing skill and (b) investment is made in training cops to be better decision-makers. I recommend his work to you.

    • Hi Adrian,

      Thank you for your comments. I have studied the variables you talk about. However, I have studied these variables in a juror context rather than a policing one. Additionally, I think heuristics can emerge out of both research and practice, and would agree that research does lead to more credible types of heuristics. I hope that my research can help inform institutions on the value of certain heuristics, and give them the credibility you speak of.

      I have read Gary Klein’s work on naturalistic decision making, and I found it very insightful. I also like the work of Herbert Simon, who discusses naturalistic decision making and satisficing.

      Finally, thank you for recommending the work of Ivar Fahsing, his thesis sounds very intriguing. Could you send me a link of where to find it ?

      Thank you again for you comments and recommendations.

  3. Interesting post and comments, thanks. It has seemed to me that one important factor in detective decision making is what they think they are trying to accomplish, i.e. “how can we get enough evidence to charge this guy?” versus “who actually did this crime and how can we get enough evidence to charge him, whomever he is?” I suppose that’s just tunnel vision, but perhaps it’s more likely when the detective loses track of the true objective of the investigation.

    In regard to police decision making generally, I thoroughly agree that it has been an underappreciated way of thinking about policing and also police administration. If one takes the view that policing is mainly a matter of making decisions, then the challenge for police leaders is figuring out how best to guide and direct those decisions. A lot of what has been written about management seems mainly aimed at “how can we get workers to work harder?” but, arguably, good policing is more about making good decisions than about working harder. I haven’t seen police supervision, management, or leadership written about much from this decision making perspective, nor, I suspect, does much police executive training adopt this perspective.

  4. Hi Gary,

    Very interesting point. I agree, I think these non-rational methods of integrating information are triggered by how the case is framed. If the detective is interested in “how can we get enough evidence to charge this guy?” , then tunnel vision will probably be promoted. Whereas, more rational decision making may be promoted when the objective is “who actually did this crime and how can we get enough evidence to charge him, whomever he is?”

    Also, I agree with your second point. A big part of policing, and most institutions, is decision making. More research needs to be done on the decision making processes of police officers, what is optimal decision making in relation to policing, and what variables attenuate negative heuristics. Exactly Gary, I think that most institutions need some level of education on decision making theory and the value of heuristics.

    Thank you for you comments, I found them very thought provoking. Please do not hesitate to contact me further, I would like to continue this discussion.

  5. Pingback: BLM Follow-Up – Open Source News

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s