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Based as it is on a simple truism and five fallacies: equivocation; ambiguity; precognition; post hoc ergo propter hoc; and the ‘social absolute’ the notion of 'opportunity' , which is central to so called ‘Crime as Opportunity Theory’, cannot logically be a cause of crime.
This essay seeks to get to grips with what I see to be the barrier to crime reduction knowledge progression that has been thrown up by two criminology theories/approaches: Situational Crime Prevention (SCP) and Routine Activities Theory (RAT). This problem is caused by the policy oriented popularity of SCP and RAT that is likely due in no small part to their simplistic and easily comprehendible, compelling, yet ultimately illogical weird focus upon describing the data of crime in ever more complex ways so that simple truisms about the scenes of crime and potential crime are placed in the spotlight and presented as a root cause of crime. Yet, as this essay reveals, this notion of opportunity is, in fact, the very data that a true testable theory of causation could explain.
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On why Opportunity Cannot be a Cause of Crime
Criminological concern with the need to fully understand the notion of opportunity and to examine claims that ‘opportunity is a cause of crime’ stems from the fact that many key academic proponents of the Situational Crime Prevention (SCP) approach, and Routine Activities Theory (RAT) – who have been collectively labelled Administrative Criminologists (Young 1994) – are now claiming to be scientists working in the mould of natural scientists under their own self-styled designation as Crime Scientists (Laycock 2003; Pease 2008) and claiming that their notion of criminological opportunity is the most important cause of crime (Felson and Clarke 1998; Tilley and Laycock 2002; Laycock 2003).
My identification of logical problems with the RAT notion of opportunity caused me to conclude that it is not a scientific explanation for causality, but is instead a mere truism. The essential argument is that the RAT notion of crime opportunity - described as an 'opportunity theory' by its own author, and by the originator of SCP, Ronald Clarke (e.g. Felson and Clarke 1998: p. v), is pseudoscientific (Popper 1976) because it is based on what is an elegant description of the data of a successful crime in commission (see Fig 1 below). This makes it a truism (as opposed to a tautology - this tautology claim is a long standing criticism of Crime Opportunity Theory. But it is something of a red herring). Being a mere truism, the RAT notion of 'opportunity' is something that is incapable of empirical testing and falsification. These arguments are more fully laid out in two earlier essays that I wrote on the subject, which can be found on the Dysology website.
Note: The basic problem is that the RAT notion of opportunity for crime is based on the Classic RAT Triangle that describes the essential elements of a successfully completed crime only (see Fig 1). But what of all those perceived opportunities that don't work out for the offender? Illogically, the RAT notion of opportunity is based on information that nobody can know until after the crime is successfully completed. Nowhere does Felson ever tell us that his RAT notion of 'opportunity' has anything to do with the offender's perception of guardianship - or the victim's and/or guardian's perception of the offender's relative capability come to that. Neither do Felson and Clarke (1998).
This, my third, essay on crime and opportunity seeks to understand the reasons why the authors and followers of RAT, SCP and Crime Science, and their critics, failed to identify this problem. I conclude in this essay that the reason they all failed to spot it seems to be based on a failure among all crime as opportunity theorists to clearly and consistently define what they mean by opportunity or by guardianship.
Criminology theory clearly has implications for criminal justice and crime reduction policy making. Because irrational or simply wrong theory is likely to, at the very best, lead to some beneficial policy driven practice but perhaps not the most effective and if it is effective then it will be so in ways that are not intended and by ways that are not understood. At worst it can be lethal (for either offenders or their victims) – either directly or else over time by way of focusing our attention away from developing knowledge in terms of crime casualty. As Einstadter and Henry (1995: p.18) explain:
Assumptions made about crime causation have direct implications for criminal justice policy and about how actions towards offenders are justified, which in turn colors the way the institutions and procedures of justice will be used. Whereas a society may punish offenders based on specifications in criminal law, criminological theorists are concerned with overall policy, based on the logic of their theoretical analysis. …For criminological theorists, then, the main constraints on policy and accompanying correctional ideology come not from law, political expediency, or empirical efficiency, but from the logic of their own theoretical analysis.
In this essay I essentially argue that the classic RAT crime triangle misleads us because if we continue to irrationally accept its three components (that in reality describe only a successfully completed crime in commission) as a cause of itself (crime) then we have no reason to consider motivation, perception or contingency - which is why these three crucial elements have been ignored in Crime Opportunity Theory. In another essay (Sutton 2012), I explain how understanding more about motivation, contingency and perceptions might take knowledge forward in the area of crime causation, particularly wth regard to the role of real crime opportunities as a cause of crime and how best to reduce them.
The Fallacy of Equivocation
Equivocation is a logical fallacy that occurs when the same term is used in different senses in order to make an argument. An example is: "The water vole lives in the bank. Banks are found in city centres. Therefore, the water vole lives in the city centre."
Dictionary definitions of opportunity generally describe it along the lines of being a favourable appropriate or advantageous juncture of circumstances. Unless the simple truism nature of the RAT trinity is explained (and it never is) the use of the word opportunity is naturally taken by the reader to mean that it is something that occurs before the crime takes place - and so is a cause of it. But as Essay No 1 on the dysology website explains, the RAT, SCP and Crime Science notion of opportunity is something that only occurs for sure after the crime has been successfully completed. Therefore, I would argue that the claim that opportunity is a cause of crime is an example of the fallacy of equivocation.
Some who claim that opportunity is a cause of crime have gone further to claim that it is the most important cause of crime (Tilley and Laycock 2002). To repeat the point already made, their notion of opportunity as a cause of crime is not the simple and commonly understood one for opportunity in general, which consists of a favourable, appropriate or advantageous juncture of circumstances existing prior to any action that might capitalise on it; rather it involves three things coming together in time and place after the event: (a) a suitably motivated and capable offender (b) a suitable target for that offender and (c) the absence of capable guardianship to protect the target from the offender (Felson and Boba 2010). We might call these three things the RAT trilogy or ratortunity. Those who argue for the theory of "opportunity as a cause of crime" do not explain that what they mean by opportunity is a description of what they can only know to be these three core components of a successful crime in commission after it has happened (not during, and not before) because that is the only way that they know for sure that the offender was capable of overcoming the guardianship. That alone is enough to prove that crime as opportunity theory is an example of the fallacy of equivocation because those who use the RAT 'after the event' trilogy of 'crime as opportunity' argument fail to make it clear that their notion of opportunity (ratortunity) does not mean the universally understood and more commonly understood notion of opportunity as something that occurs prior to an act that capitalises on it.
The Fallacy of Ambiguity
The philosopher Gary Curtis (undated) writes: “Because of the ubiquity of ambiguity in natural language, it is important to realize that its presence in an argument is not sufficient to render it fallacious, otherwise, all such arguments would be fallacious. Most ambiguity is logically harmless, a fallacy occurring only when ambiguity causes an argument's form to appear validating when it is not.”
Accepting Curtis’s definition of the informal logical fallacy of ambiguity in arguments, we can apply it to the argument that opportunity is a cause of crime in order to determine (a) whether it is used ambiguously and (b) whether that ambiguous use is sufficient to render the argument fallacious.
To proceed, it seems useful to first seek to establish what is commonly and most widely understood by the word ‘opportunity’ . As Garwood (2011 p.37) points out:
“The Merrian-Webster Online Dictionary defines opportunity as ‘a favourable juncture of circumstances’. In common with many such definitions, this excludes consideration of the mindset of the person faced with such a juncture of circumstances.”
In this essay we will see that the current criminological notion of opportunity as a cause of crime goes way beyond this commonly agreed dictionary definition. The criminological notion of opportunity as it currently stands includes not only the mind of the potential criminal actor but, amongst a host of other complexities, also the intrinsic incapability or actual failure of others, (a) present or (b) not even present, to prevent the crime. Most importantly, such information can only be known for sure after the crime was successfully accomplished.
Ambiguity about the RAT concept of guardianship causes further ambiguity about whether opportunity is a refutable scientific explanation or merely a description of the data of a successfully completed crime that amounts to a mere truism.
The RAT notion of opportunity incorporates the need to understand what actually happens before, during and after a crime. This goes beyond the common understanding from dictionary definitions of opportunity as being perceived as circumstances favourable to a perceived goal that the perceiver can choose to capitalise upon or pass up. As Felson (1986) explains at length:
To understand criminal opportunity, we need to know not only some of the decisions made by offenders, human targets, guardians, and handlers, but also the situations of their physical convergence as a result of these decisions, regardless of whether the decision makers know what we, as analysts, know. And we have to know the outcome. Was the offender wrong, missing a golden opportunity or committing a silly blunder? Did the getaway car stall or did the selected target trap him? Did the victim succeed by going through the day safe from crime, regardless of whether he or she thought about it? What choices on the part of a citizen produce an unplanned victimization and impair or assist guardianship of targets and handling of offenders? Indeed, a criminal situation is made possible by various decisions by those who set the stage for the convergence of the four minimal elements, however inadvertently. Any set of decisions that assembles a handled offender and a suitable target, in the absence of a capable guardian and intimate handler, will tend to be criminogenic. Conversely, any decision that prevents this convergence will impair criminal acts. Even though an offender may prefer to violate the law, his or her preference can be thwarted by the structure of decisions made by others, regardless of whether they know they are preventing a crime from occurring. In short, we cannot understand the rational structure of criminal behavior by considering the reasoning of only one actor in the system.'
Tilley and Laycock (2002) similarly perceive the criminological notion of ‘opportunity’ as inseparable from the rewards of successful offending:
‘The most significant, and universal cause is, however, opportunity. If there were no opportunities there would be no crimes; the same cannot be said for any of the other contributory causes. In so far as opportunity creates criminality by rewarding those with low motivation with success in easily chosen and completed crime, it thus comprises a root cause - as one recent paper puts it, ‘Opportunity makes the thief‘ (Felson and Clarke, 1998).’
Clarke (1984) and Felson and Clarke (1988) see the RAT explanation for crime as integral to the notion of Crime Opportunity Theory. Despite routine use of the word 'opportunity' in their work these authors fail to make it clear what they mean by it. Instead they are opaque and mysterious about what they really mean, exactly, by 'opportunity'. This might even stem from their personal uncertainty. Consider the following fogginess from Clarke (1984: 80):
'The difficulties of achieving the necessary accuracy in counts of criminal opportunities derive in large part from the conceptual complexities; opportunity is not merely the necessary condition for offending, but it can provoke crime and can also be sought and created by those with necessary motivation.'
Felson and Boba (2010) similarly fail to define with any degree of clarity what they mean by opportunity. Consider the following vagueness (p206) which seems that it might mean to imply that the RAT trilogy notion of the core components of a crime are part of what is integral to the meaning of opportunity. Although it fails to appreciate the reality of much crime where offenders offend on foot and travel to the crime scene on foot and do not rely on transport to sell what they steal:
'Crime is a process, depending on the convergence of offenders and targets in the absence of guardians. The transportation system generates these convergences. Markets for stolen goods are of central importance for generating crime opportunities, and opportunities make the thief.'
The problem is that criminologists who support opportunity theories of crime have not produced a clear or consistent definition of the criminological meaning of opportunity (See e.g. Willison 2000; Garwood 2011). The reasons for this lack of a succinct definition are very clearly stated by Clarke (1984). While never clearly defining opportunity himself, Clarke distinguishes between many types of situations and targets for crime that he loosely describes as criminal opportunities. For example, he writes about subjective assessments made by potential criminals of the ease and attractiveness of opportunities. He then mentions the fact that some offenders go hunting for opportunities, while others manipulate the world so as to create them or plan for them when they occur. He says that some opportunities relate to routine activities or the situations in which crimes take place and to differential vulnerabilities of targets and differential attractiveness between targets . Clarke ultimately concludes that it would be extremely difficult to quantify opportunities in society due to these conceptual difficulties. This presents a problem for crime science if, as Laycock (2003) writes, it is to be founded on the premise that opportunity is a cause of crime. We can see from Felson's (1986) attempt to explain the complexity of his notion of crime opportunity, and from reading Clarke's (1984) paper, that the notion of opportunity as a cause of crime is a complex idea in need of an equation.
Clarke's own failure to get to grips with a clear definition of what he means by opportunity is a good example of the fact that we must always bear in mind, when considering arguments that opportunity is a cause of crime, that those who believe this consider opportunity to be many different things and this makes their notion of it not only very complex but also very ill-defined, which results in its idiosyncratic usage in ambiguous arguments - such as (Felson and Clarke 1998 p. v: '...opportunity is a root cause of crime.' My contention that this argument is ambiguous is something that the remainder of this paper seeks to demonstrate.
To compound this problem, Felson is also ambiguous about the meaning of guardianship. On page 28 of his fourth edition of Crime and Everyday Life (Felson and Boba 2010) the author’s write that the third almost always’ element of a criminal act is: ‘The absence of a capable guardian against the offence.’ Their notion of guardianship is that it must be capable only twice - on pages 28 and 47. Elsewhere in the book (pp. 30, 31, 32, 33 and 180) on five different pages the presence of a person is sufficient to make them a guardian that may deter crime (note Felson and Boba do not say it will in all cases) – there is no mention of them needing to be capable. Criminology geeks might be interested to learn that in the third edition of Crime and Everyday Life (Felson 2002) Felson uses the term ‘capable guardian’ three times (pp. 21, 35, 79) and ‘guardian’ alone three times. Both terms are used by Felson (And Felson and Boba) as though they mean the same thing. But, as this essay will show when explaining Fig 2 (below) there is a world of difference between what these two phrases actually mean.
Fig 1. Felson's basic and classic Routine Activities Triangle, shown above, is used by countless academics, police and government departments to guide their understanding and crime policy making (e.g. Anderson 2010).
The diagram above, (Fig 2) revelas for the first time the logical variations of how Felson's classic RAT crime triangle (Fig. 1) must logically influence RAT's notion of crime opportunity, because Felson does not offer any other theoretical explanation for what makes a crime opportunity. As Fig. 2 reveals, Felson sometimes uses the term ‘absence of guardianship’ to mean (G1) the absence of any person (regardless of their actual intrinsic guardianship capabilities) to serve to create opportunities for crime. By default, the presence of any type of guardian serves to reduce criminal opportunities. And this is a testable hypothesis. For example, to take this hypothesis to the extreme, Crime Scientists might conduct a controlled experiment using life-size cardboard cut outs of people (even mock-police officers) to measure their impact on crime reduction.
On other occasions, as the opposite of Felson's classic G3 explanation for opportunity, RAT's notion of crime 'opportunities' must occur in the presence of incapable guardians (G2). On some occasions, Felson alternately uses guardianship to very specifically mean (G3) ‘capable guardian’, and here he uses its absence to describe the necessary component of a successfully completed crime. By default, therefore, RAT’s G3 ‘capable guardianship’ is either an-as-yet-undiscovered-by-mankind intrinsic and somehow known-in-advance capability that is superior to somehow, as-yet-undiscovered-by-mankind, known-in-advance offender capabilities - or else it must theoretically have been an actually deployed and proven presence that is a necessary component in successfully preventing an attempted crime, not just preventing an otherwise favourable juncture of circumstances for a crime that nobody tried to capitalise upon. Therefore, both G2 and G3 models must underpin the RAT notion of crime opportunity, yet both contain information that cannot be theoretically known until after the theoretical crime has been completed, which makes them both the data of successfully completed crime acts, which makes both G2 and G3 irrefutable truisms, rather than refutable hypothesis that can be empirically tested in the field. This is true, for example, because an offender might attempt to commit a crime in the initial absence of a capable guardian, but then be thwarted when one suddenly turns up. Logically, therefore, only G1 is theoretically capable of existing as an opportunity before the crime is committed.
Note: The basic RAT crime triangle (Fig 1) is used in this critique because it is the foundation upon which Felson’s more recent triangle (Fig 3) is built. I contend that the more recent and complex version of the triangle (e.g. see: POP Centre) in Fig 3 is simply an exercise in overlaying more truisms over the original (see Fig 1) , which simply overcomplicates and adds multiple layers of seemingly tautological complexity to the original.
For the purposes of seeking to achieve clarity, it is perhaps worth examining at this point whether or not there are any implications in the seemingly random interchangeable use by crime opportunity theorists of the terms 'motivated offender' (e.g. Felson 1993; Brantingham and Brantingham 1993), 'likely offender' (e.g. Cohen and Felson 1980; Felson and Boba 2010) and 'potential offender' (Farrell et al 2005). Such seemingly random usage may even occur within texts (e.g. see Farrell et al 2005). To add to the slightly baffling confusion that might arise from the way crime opportunity theorists use these terms interchangeably, they are also known to use them in moderately baffling ways. For example, Brantingham and Brantingham (1993: p. 262) write: 'Neither motivated offenders nor opportunities for crime are uniformly distributed in space and time'. It seems that while such mixing of terminology may be confusing, that, ultimately, these three terms must all mean the same thing. Namely, capable offender. Although the term capable offender does not appear to have been used by any of these authors, the use of all or any of these other three terms in the context of the description of crime provided by RAT basic crime act triangle (e.g. Felson and Boba 2010: p.29) must infer that all of these offender descriptions mean capable offenders (as well as motivated offenders) since they are part of the RAT criminal act triangle only because guardianship is necessarily incapable when such a crime act (other than a failed attempt, which is an outcome that is curiously never considered) occurs.
If crime opportunity theorists were to re-think their definitions, accepting that their RAT notion of opportunity is so different from its etymological meaning that it has no predictive ability, they might seek to develop measurable and findable values for vulnerability, for offender capability, and for offender motivation. These could then be tested by way of prediction, regarding likelihood of successful victimisation in a given time period, and attempted empirical falsification and subsequent improvement. Surely this is what we should expect of a real crime science?
To summarise, you cannot know for sure that a guardian is incapable or capable, relative to an offenders ability, until after a crime has been successfully completed, or else an attempt prevented. It is odd that two out of the three RAT models that must underpin RAT's notion of crime opportunity (G2 and G3) can only be known to exist after the crime is successfully committed. We can see, from this logical analysis, the theoretical limitations that arise as a result of RAT not having a clear definition of opportunity and of its reliance upon both stated and unstated truism models of a completed crime act to create a pseudo scientific notion of opportunity as a cause of crime. In short, the current RAT notion of opportunity as a cause of crime is based on the irrational theoretical premise that the crime it seeks to explain caused itself to happen.
Fallacy of the Social Absolute
The problem with G1 (see Fig 2, above) is that even this model may not even represent reality for most cases of feasibly possible potential crime scenes. To begin to examine this problem we need to ask: what does ‘absence’ of any kind of guardianship mean in RAT? We know it is probably not meant as an absence perceived by the offender because that notion is never explored by Felson in any of his writing on RAT, nor by Felson and Clarke (1998). So absence of guardianship in RAT is almost certainly meant to mean (Type A) ‘physically absent’ that there are absolutely no other human beings physically around at the potential crime scene. However G2 and G3 could be re-imagined to mean (Type B) perceived to be ‘conceptually absent’ because the potential guardian is physically present, but with an absence of any possible or potential-offender-perceived guardianship ability of any kind.
In other words we need to ask: does (Type B) mean that that there are other human beings physically around (or perhaps CCTV or even faux human beings that aim to fool potential offenders into thinking they are real – such as life size cardboard cut-out police officers), but they do not in reality have the potential or intrinsic ability, or else cannot even create the perception in the mind of the offender that they could prevent the crime? If G1 means (Type A) then it represents an opportunity of that kind, which can be empirically tested. However, if on another occasion G1 means (B) (G1-Type B’) then how can we possibly know for sure, in advance of the crime being successfully completed, that the physically present person is really conceptually absent as any kind of guardian? The answer is that we cannot. A physically present person of any kind may be perceived to be conceptually absent, to the offender, as any kind of guardian, at the time the offence is being carried out, but that offender may get an unpleasant surprise and find out he/she was wrong.
This means that a ‘G1-Type A’ opportunity is quite easily capable of being known in advance of a successful crime being completed. And that is why this type of RAT opportunity is realistically capable of being empirically tested as a cause of crime (rather than found to be a truism after the event). Fortunately, we probably can test for the impact of a G1-Type B opportunities as a cause of crime as well - so long as we can find ways to know the mind of the offender at the point of the commission of the crime. The use of imaginative mock-crime scenarios may present some potential for future research in this area.
It is by no means a perfect analogy, but one useful example to begin thinking about how G1-Type B opportunities are based on unknowable outcomes are major sporting upsets. Here we must think of the notion of opportunity from the point of view of the contenders. Imagine the title at stake as belonging to the hot favourite and the underdog contender as the ‘thief’ hoping to ‘steal’ the title.
Before the start of a world title boxing match, for example, does the rank-outsider challenger consider the title holder – who’s crown he hopes to ‘steal’ - a capable guardian?
Of the three classic RAT triangles that inform the Opportunity Theory of Crime, only G1 is capable of consideration for this question. And within that model, only G1-Type B can possibly apply.
The excellent boxing website RandyTurpin.Com provides some data on a classic boxing story for us to consider. In the first of two blistering boxing matches the British underdog Turpin caused a major sporting upset by dethroning the American champ Sugar Ray Robinson – a man said by many to be the greatest pound-for-pound boxer who ever lived.
Sugar Ray Robinson v Randolph Turpin I – the data
- On July 10th 1951, Robinson was the World Middleweight champion, was 91 fights undefeated, and had lost only once in his 132 fight career.
- Turpin was British and European Middleweight champion, and had won 40 of his 43 contests.
- Turpin was widely considered to be way "too young and inexperienced" to defeat the World champion Robinson.
- Robinson was 4-to-1 favourite to win. Turpin was 20-to-1 to win on points. Result: Turpin clearly won on points and became the new middleweight boxing champion of the world.
Turpin agreed to a rematch to take place only 64 days later, in New York, USA
Sugar Ray Robinson v Randolph Turpin II - the data
- On September 12th 1951, Turpin was out to prove that his victory was no fluke, whilst Robinson was determined to avenge the defeat and regain the title.
- Robinson was a 2-to-1 favourite to win. Turpin a 6-to-4 underdog.
- Turpin lost when the fight was stopped in the 9th round due to his failure in that round to fight back against Robinson’s intense punching.
(Q) Taking the logic of the Opportunity Theory of Crime, which is based on the classic RAT 'crime act' triangle, how might we consider the ‘opportunity’ for Turpin to ‘steal’ Robinson’s world title in their first encounter?
(A) Firstly, we could not know in advance that Turpin was a relatively more capable competitor (offender) for the title (target) than Robinson was as owner (guardian) of it. Therefore, G2 and G3 are wrong as explanations of ‘opportunity’ for Turpin to win the title or for Robinson's opportunity to successfully defend it – at least not if we consider an opportunity to be something that exists prior to an action to capitalise upon it. Secondly, G1-Type A does not help us here either, since it requires a physical absence of any kind of guardianship and Robinson was not physically absent from the fight (and neither was Turpin come to that). In terms of the opportunity for Robinson to successfully defend his title - or for Turpin to win it - G1-Type B can only help us if we could know the respective states of either Robinson’s or Turpin's minds in the first boxing match. In the case of Robinson for instance, he might have considered this fight with Turpin to be a G1-Type B opportunity to successfully defend his title, because, prior to knowing the outcome of the fight, there is no other RAT opportunity type. But how did Turpin actually view it? The only possible RAT answer is that Turpin must have seen it as a G1-Type B opportunity as well. This is the only RAT notion of opportunity that is left available for us to consider, and it is far from perfect because to accept it as theoretically sufficient we would have to work on the premise that both fighters absolutely considered the other to be incapable (conceptually absent). Having done a little boxing myself, I very much doubt that would have been the case where two rational professional boxers are concerned.
Furthermore, both the Turpin v Robinson fights serve well our understanding of why RAT G2 and G3 ‘opportunity’ models are merely truisms, as opposed to known and testable entities prior to the commission of the act. Because Robinson was only an incapable guardian of his world title after he lost, as was Turpin only known to be incapable after round 9 in the re-match. In both cases their 100 per cent knowable ‘absence’ as guardians never existed before the event was over. What this example shows us is that it is unlikely that offenders and guardians alike will always consider guardianship in binary terms as either conceptually present or absent. The notion of guardianship in terms of opportunity - prior to action made possible by perception of it - is sometimes (depending on the type of guardianship situation) on a spectrum of perceived capability.
Moving back to crime to consider G1-Type B offenders' perceptions of a person’s potential guardianship capability, we can see an obvious potential personal risk for the offender making a wrong assessment. And this is well evidenced by all those heart warming stories of unlikely ‘have-a-go-heroes’ thwarting an offender's immediate criminal ambition and in the routine hoodwinking of offenders by well disguised police officers acting as prostitutes, drug addicts or other official sting operations. In reality then, it is not only potential offenders, but also potential guardians who may choose to capitalise on a conjunction of favourable circumstances to go after their target.
Of course, the usual day-to-day reality of how offenders asses guardianship is likely to be somewhere in the middle between outright perception of 100 per cent capability or else 100 per cent absence of capability. Meanwhile, at the opposite side of the story to how two skilful and powerful professional boxers are likely to rationally assess one another are those involving drunk offenders. Consider all those – the exception proves the rule - type of news stories. For example, there is the memorable one about a pair of British drunks attacking cage fighters dressed-up as drag-queens, and there are much more serous cases involving drunken thieves, being electrocuted stealing live copper cable. That these stories are exceptional proves the point that it’s really not a binary world involving most offenders making RAT-type decisions about human guardians being 100 per cent capable or not. The latter example should also awaken our academic sensibilities to the importance of our theoretical work in terms of how it influences real-world crime reduction policy making. Despite my jokes, this subject area is deadly serious because people die from poor policymaking in the field of crime.
Currently, the influence of the self-referential RAT notion of opportunity on knowledge progression is that policy makers and practitioners are being seduced by its unapt simplicity to the extent that they are failing to focus adequately upon where progress could be made by way of understanding more about the role of target vulnerability in opportunity structures for crime. For example, as it is currently understood, the RAT notion of opportunity can only consider an open window to be an opportunity for theft or burglary if the crime is successfully completed. And yet we know, from interviewing them, that burglars do flee homes empty handed if they are disturbed - or if they can find nothing inside worth stealing. Understanding more about the interaction between opportunities and failed attempts is as important for recognising what works in crime reduction as understanding the reasons for successful crimes.
A fourth fallacy then, the fallacy of the social absolute, underpins the RAT notion of crime opportunity, based as it is on the RAT crime triangle where all capable guardianship is absolutely absent. The error of all such binary notions in the affairs of mankind is perfectly explained by William James (2008: p.42):
‘As absolute, or sub specie eternitatis, or quatenus infinitus est. As such, the absolute neither acts nor suffers, nor loves nor hates; it has no needs, desires, or aspirations, no failures or successes, friends or enemies, victories or defeats.'
Seeing reality outside of RAT's impossible notion of opportunity allows us to identify a new and important question for crime opportunity theory that it has, to date ignored. Namely, how does the RAT notion of crime opportunities fit with immediate crime prevention opportunities as they are perceived by different types of guardian? To date, RAT has only considered this element from the perspective of the potential offender. Crime opportunity theorists wishing to analyse G1-Type B offenders' perceptions of guardianship would be making a big mistake if they sought only to measure whether all offenders thought capable guardianship was simply present or absent. Reason suggests that they should seek also to understand to what degree offenders perceive certain types of guardianship relatively inferior to their own abilities and why. Research of this kind, conducted in the field, would enable opportunity theorists to tell the difference between more fully rational choices (those who had a really good rational - weighing up of all the pros and cons - think about it), pseudo-rational choice (those who thought about it just for a bit) and irrational choice (those who were intoxicated, deluded or pretty much totally spontaneous).
In terms of whether or not a particular crime has been committed, the law tends to think of the offender’s intentions and his actions as having either happened or not. So, if he perceives an opportunity and chooses not to act upon it then no crime has taken place. Alternatively, if a burglar orchestrates an opportunity to burgle a commercial property by conspiring with others and an informant tips off the police, then he will be thwarted before he attempts to break in, but may be charged with conspiracy. If he attempts to break in, but is thwarted by physical security, canine or human guardianship, then he has committed the offence of attempted burglary. If he breaks in, but is disturbed or thwarted inside by similar guardianship or internal security he may take some items with success, but have to leave others behind. He may complete the burglary, and yet be arrested on leaving the premises. He may leave to premises but be arrested in possession of the stolen goods before he can sell them. Or he may temporarily stash the stolen goods in a nearby garden only to have them found and removed by someone else – perhaps another thief or curious children - before he can sell them. He may find he is unable to sell the stolen goods, or else he may be arrested during the sale, or shortly afterwards, possibly following a tip off from a fence or member of the general public. He may, as often happens, be arrested several days or weeks later on the basis of forensic evidence such as a finger print or DNA left at the crime scene.
For the thief, therefore, both the theft itself and stolen goods trading typically involves several steps, beginning with the theft itself and culminating in an end consumer obtaining the stolen goods. Some of these steps have ideal but not absolutely positive or negative outcomes, such as getting a satisfactory haul from a burglary and getting a satisfactory price, rather than having to leave promptly with less property, or not sell it for a satisfactory price. Even remaining at large for several weeks following a burglary for which he will eventually be convicted is more of a positive outcome than immediate detection and arrest. Other steps, such as overcoming physical security and avoiding immediate detection or apprehension by a guardian, have binary outcomes of absolute success or failure.
Since most thieves steal property in order to sell it for cash (Sutton 1998), the various steps involved for successful completion, following an initially successful crime of theft are depicted in Figure 4 below (from Sutton 2010).
For the offender, if not the law and the RAT crime triangle, crime is a process. The way the law sees a crime as having been committed is far simpler than what an offender sees as a crime having been successfully completed. Seeing crime from the point of view of the offender reveals why the appealing simplicity of RAT crime triangle is actually what makes it simply inadequate.
The Fallacy of Precognition
There are three reasons why the overall RAT notion of crime opportunity as it is currently understood cannot include opportunities that offenders are capable of perceiving: first, it is not an opportunity that a potential offender can choose to ignore because he is by now deemed (albeit impossibly) to have successfully committed the crime; second, it follows that it is not based on a notion of opportunity, which if acted upon, could result in a failed attempt; and third, it is based entirely upon the classic RAT crime triangle model (Fig 1) of a successful crime in commission, which means that it relies upon the underlying assumption that any offender who perceives the opportunity knows in advance that their criminal action will be successful (something which is impossible to know with certainty - just ask anyone who has ever attacked a cage fighter going to a fancy dress party in high heels and cocktail dress).
If the RAT crime opportunity is one which the potential offender at a potential crime scene can recognise then in order to do so he would need know things that are impossible to know without access to return-ticket time travel, or else he would need to possess precognition. At the time of writing, human time travel to the future and back has not been accomplished. Moreover, since nobody has yet won the pot of accumulated prizes on offer that amount to over $2m (US) for proof of psychic abilities, RAT crime opportunity theory is wrong whenever it is used to interpret offender decision making. Therefore, at least in this regard, the RAT opportunity theory for crime is based on what we might here name the fallacy of precognition.
The Post Hoc Fallacy: The fallacy of assuming that temporal succession is evidence of causal relation
Because the RAT notion of opportunity is based upon the fallacy of offenders having precognition it follows that it is also built on the following premise: Because absence of capable guardianship is a condition of every successfully completed crime, all offenders rely upon this fact in order to commit the crime, which means that it is therefore a cause of the crime. The term post hoc comes from the logical fallacy: post hoc ergo propter hoc (after this, therefore on account of this). The RAT notion of opportunity is clearly a post hoc fallacy.
Post hoc fallacies of causation are actually more ludicrous than dleightfully bizarre comedy shows. For example, the Monty Python TV comedy series produced a classic sketch where John Cleese, in character as a Miss Anne Elk, has a theory “On Brontosauruses”, which is essentially that they are all thin at one end, fat in the middle and then thinner at the other end. Notably, even the Python team did not go so far as to have the “owner” of this theory on brontosauruses (which is in fact a truism) believe that the shape of a brontosaurous is what causes it to be one.
Some Logical and Veracious Reinterpretations of the Crime Opportunity Myth
Most opportunity theorists, including Clarke and Felson, appear to consider the RAT crime triangle notion of opportunity to exist as a fixed certainty before a crime is even committed. However, some scholars do get much closer to reality.
Weaver and Carroll (1985) discovered that novice shoplifters perceived the likely effectiveness of observed security measures and other guardianship in very different ways to expert shoplifters.
Tilley (1993) theorizes about offender perceptions and not certainties where he speculates about about how crime prevention measures to protect previously victimised homes might change repeat-offenders' perceptions:
“… Kirkholt was a high crime area, that it was clearly circumscribed, and that it was culturally homogenous are features of the context in which the project was established. The removal of meters, the establishment of cocoons and the target hardening of already victimised dwellings were measures taken, which in turn triggered mechanisms which might include, respectively, increasing the offenders’ perceived risk of recognition and apprehension, removing incentives to burgle the property, and rendering more difficult and more risky entry to properties hitherto found to be most vulnerable.” (Tilley 1993: 14)
Similarly, Farrell et al (1995) do consider the characteristics of target vulnerability to be something that offenders perceive in advance of committing a crime, rather than something that is so. Incongruously, however, in seeking to make sense of repeat victimisation, they then go on to describe previous criminal success against a target interchangeably as something that makes the target ‘known’ to be suitable (p.391) – which is logically impossible - while elsewhere (p.396) they veraciously describe previously victimised targets as something that repeat offenders can only ‘perceive’ to be suitable:
“A burglar walking down the street where he has never burgled before sees two kinds of house - the presumed suitable and the presumed unsuitable (by dint of occupancy, alarm, barking dog and so on). He burgles one of the houses he presumes to be suitable, and is successful. Next time he walks down the street, he sees three kinds of house – the presumed unsuitable, the presumed suitable and the known to be suitable. It would involve least effort to burgle the house known to be suitable.” (Farrell et al 391)
Contrast that with the more logical acknowledgment that 'opportunity' depends upon perception, not knowledge of certainty or the pre-existence of certain outcomes:
“Offences against the same target by the same offender are based on the experiences of the previous victimization, and perception of known risk and rewards. This rational choice is based upon the motivated offender's greater knowledge of the victim's suitability and the likelihood of the absence of capable guardians.” (Farrell et al 396).
DISCUSSION OF THE MYTH THAT OPPORTUNITY IS A CAUSE OF CRIME
I suspect that the confusion between fixed properties of 'opportunity' and offenders' perceptions of target vulnerability that have led to confusions about causality and truism in the RAT notion of opportunity is in no small part due to the way it has been described by its originator and his various co-authors. For example, Felson and Clarke (1988) could hardly describe more positively the components of the classic RAT Triangle as though they are things that exist as a known and permanent state of affairs before an offender attempts to succeed, rather than what can only be known after an offender has managed to succeed:
‘The routine activity approach started as an explanation of predatory crimes. It assumed that for such crimes to occur there must be a convergence in time and space of three minimal elements: a likely offender, a suitable target, and the absence of a capable guardian against crime.‘ (Felson and Clarke 1988: p. 4)
Furthermore, this notion of the RAT and SCP discovery of some kind of universal law at work regarding the belief that opportunity is is an objective reality rather than something that needs to be perceived to exist, which is probably reinforced by Felson's repeated reference to his crime triangle as 'the chemistry of crime' (See Box 2, page 4 Felson and Clarke 1988; chapter 2 Felson 2002; and chapter 2 Felson and Boba 2010) and the fact that this is confusingly labelled (Felson and Clarke 1988) as 'The New Opportunity Theory' and then immediately and weirdly followed by the caveat that it’s probably not a theory at all. So why call it one in the first place? Perhaps because what we are witnessing here is evidence of a struggle between knowledge of the need to seek veracity and the desire to create an influential stylistically definable discourse that is expressing the strong components of the semantic system of the natural sciences, which is one reason why all such myths are created. Namely, in order to solve complex social problems as elegantly as pure mathematics (Maranda 1972).
The equivocal use of the meaning of guardianship by Felson in the above (Felson and Clarke 1988 e.g: see elsewhere on page 4), and his various other works on RAT, by way of vacillating randomly between two distinct, yet unacknowledged, types makes the argument that opportunity is a cause of crime fallacious. Because if the guardianship component of RAT opportunity must be a capable one to prevent crime then it must be incapable guardians that allow a crime ‘opportunity’ to take place, but that can only be known for sure after the crime has been successfully completed, which makes it an irrefutable truism and not an opportunity awaiting an action to capitalise on it. If, however, the guardian needs merely to be anyone - with any degree of incapability – to serve a role in reducing, to some degree of success, crime opportunities from existing, then this weaker (G1) notion of guardianship is not a truism but is instead the sound premise upon which to build a scientific hypothesis for the RAT notion of ‘opportunity’ as a cause of crime because it can be tested to see if it can be refuted by empirical research, which fulfils Popper’s criteria for scientific explanations.
Two pillars (G2 and G3) of the three that support all RAT-reliant opportunity theories of crime are wrong
Those who promote the opportunity theory of crime need to develop scholarly vigilance against what appears to be a tendency towards confirmation bias in their published work in order to allow for greater consideration of disconfirming evidence. The current situation is that RAT and SCP adherents are characterised by their biased systematic collection and parading of many weak and unapt confirmatory examples – such as, for example, suicides from coal gas (Clarke and Mayhew 1989). This classic SCP coal gas / natural gas suicide example is cherished by both SCP and RAT adherents, who use it to promote their belief that opportunity is a cause of crime, but it is unapt as an explanation for crime or deviance because of the fact that suicide by coal gas, via the kitchen oven, was something done by (a) people suffering from depression and (b) it was the only painless and culturally acceptable form of suicide available in the home at the time. So it was not just that one important opportunity had been removed - it was that the only known option of affordable and painless suicide had been removed. This meant there was no acceptably alternative known method to which those with suicidal tendencies could be displaced to. And yet Clarke and Mayhew (1989) claim that the gas suicide story is evidence that specific types of crime opportunity reduction does not simply result in crime displacement to all those other relatively vulnerable targets in society.
Another cherished, but unapt, RAT and SCP example of the importance of opportunity as a cause of crime is the claimed affect of compulsory helmet legislation on the reduction of motorcycle theft (Mayhew, Clarke and Elliot 1989). However, they fail here to consider that – rather than simply reducing so called 'opportunities' for theft – this new law effectively required any would-be motorcycle thief to wander the streets on foot while visibly going equipped for theft with an unconcealable crash helmet in search of a suitable target. This legislation caused, not so much a reduction of opportunity – at least not in dictionary definitions of what opportunity means - as an introduction of the need for thieves to look much more suspicious than previously, which may have played a large part in the decline of this offence. The real problem is that those writing about opportunity and this crime at the time oddly never interviewed the very subjects of their research, namely motorcycle thieves. Had they done so they might have had a chance to better understand how the law impacted on their criminal behaviour, where, when, why and with what effect.
With regard to paying even-handed attention to disconfirming evidence for their claim that opportunities alone are the most important root cause of crime, Opportunity Theorists would do well to consider why it is the case that in so many quaint and affluent English villages those honesty cash boxes for unmanned organic vegetable stalls are not stolen? I suggest they might wish to consider conducting some empirical research to test their assumptions that opportunity alone is the most important root cause with controlled experiments, with such honesty box set-ups, in different rural and urban settings with contrasting levels of affluence.
In the final analysis, the Routine Activities Theory is Brilliantly Wrong.
The medical notion of the four humours of the human body that was adopted and systemized by the ancient Greeks at around 400 BC dominated medicine up until the end of the nineteenth century - blood (hot and moist and airlike), phlegm (cold moist and waterlike), yellow bile (hot, dry and firelike) and black bile (cold, dry and earthlike) - and led to the irrational notion of treating people through bloodletting, along with a host of other irrational and harmful treatments, that continue today as bad alternative medicine (Wanjek 2003). The RAT notion of opportunity as a cause of crime is not quite as brilliant in its thoroughness and appeal as the notion of the four humours. But it is equally as irrational and wrong. Hopefully, it will not endure for two millennia.
Understanding the Power of a Criminological Myth
Perhaps the RAT triangle as a cause of crime represents the power of the small and clever myth over those larger and more clumsy rhetorical arguments offered by the wishful thinking of certain sections of the academic left. Maranda (1972, 16) summarises the power of the simple myth: ‘ …a culture’s myths contain its semantic jurisprudence. Whether this can be reduced to an algebra depends on the power of the analyst.’ Thinking about this, it might be that the RAT triangle, being a triangle, signals veracious triangulation, which for time time now has been a respected way of checking results by employing more than one empirical research method.
Barthes ( 1973: 110-111) provides some insight as to how this might be so in terms of analysing myths through the science of semiotics: ‘…pictures, to be sure, are more imperative than writing, they impose meaning at one stroke, without analysing or diluting it.’ And: ‘This does not mean that one must treat mythical speech like language; myth in fact belongs to the province of general science, coextensive with linguistics, which is semiology.’
More research, it seems, is needed if we are to seek to understand the possible significance of the RAT triangle and its three classic components as signifiers of truth by criminologists who have accepted it as evidence that such a precise and elegant description of the data of a successful crime can be an explanation for itself. Why the guardianship component of the RAT triangle has never been described by its originator and the vast majority of Crime Opportunity theorists as something that is determined by the offender's perception is an area in need of further research. Perhaps it is because this would break its mythical power as the closest thing criminology has to a scientific equation for crime causation?
To avoid ambiguity we need a Crime Science equation for the old saying: 'opportunity makes the thief' that is based upon a clear definition of the criminological notion of opportunity. Felson and other writers in the RAT field should ensure their work is clear about which of two very different possible types of guardianship is in the RAT notion of crime as opportunity, because the current ambiguous use of the term makes arguments that opportunity is the cause of crime logically fallacious. The ambiguous meaning of ‘guardian’ in RAT taints Crime Science with the mark of pseudoscience (Parke 2000) and undermines RAT. The heart of the problem is in Felson’s seemingly random switching between use of ‘absence of guardianship’ with 'absence of capable guardianship' as one of three essential elements of a crime which is compounded by their secondary use by Felson and others in badly defined notions of opportunity as a cause of crime. Felson, and those who support RAT as an opportunity theory for crime could do worse than sort out this confusingly ambiguous theoretical area.
Breaking the RAT notion of crime as opportunity down into three clearly distinct, yet previously unarticulated subtypes, one of which can be further split into two sub-types allows us to see that only one of the three main sub-types (G1) is logically valid as a possible cause for crime. The remaining two are irrefutable truisms and so cannot, rationally, be the cause of themselves. The sub-type G1, which can be tested by empirical research, should be tested in order to determine the roll of opportunity as a possible cause of crime.
This highly specific critique of RAT is necessary for the development of a real crime science, because composing a logical, theoretically sound and refutable equation for crime opportunity is the sort of thing we would expect a real science of crime to do. Read and Tilley (2000) argue that much crime prevention is not rocket science. That may be so, but launching a scientific opportunity theory for crime might well turn out to be more complex than one for launching a rocket.
If having read this far you think there still might be something rational or useful about the RAT notion of crime opportunity then consider the following scenario.
The vault of the United States Bullion Depository at Fort Knox holds at least $278 billion dollars’ worth of gold. It is deemed impregnable. Were crime scientists to assign a measurable and discoverable value upon its level of vulnerability to theft (which they have never done because doing that would mean they might be proven wrong in empirical testing in the field) it would probably have to be placed at or around zero. As far as RAT theory is concerned the vault at Fort Knox has never been overcome because guardianship is more capable than any of the motivated offenders out there. In effect, all offenders wanting to steal the gold from Fort Knox are incapable.
But what if I have just invented a teleportation device such as those used on the Stark Trek’s Star Ship Enterprise? Well, before you guffaw at such a childishly naïve idea and click to another more sensible article on the internet you might be wise to read up on what quantum physics is getting up to these days click here.
Ok – so imagine that we are living now some 300-1000 years in the future. And I’m a rogue scientist who has secretly developed a way to teleport living or heavy matter without needing to first destroy it. And, being a rogue, I decide to teleport myself and another teleportation device into the vault of Fort Knox. And then I teleport myself and the entire contents of the vault back to my secret underground bunker somewhere in Britain.
What does this caper mean for crime opportunity theory?
Overnight, all the crime opportunity theorists (perhaps one might even be a member of Felson's future family tree) will have been right all along about the reason Fort Knox was overcome. Great , Great, Great, Great, Grandfather Marcus Felson was never wrong all those years ago either. Some will be on the TV and others writing academic articles to explain that the reason the gold was stolen is because the guardianship was incapable compared to the offender’s capability. Well duh!
Surprisingly, even the law is less of an ass than, so called, Crime Science and Crime as Opportunity Theory in this regard. For example, police capture houses that operate by leaving windows open or doors unlocked, in order to be able to secretly video record active burglars to prove that they are burglars, are not seen by the law as cases of entrapment - because that's what people normally do. Normal people leave their windows open sometimes. Open windows do not cause crime. If they did then lawyers would be able to make the case that the police using open windows on capture houses caused the burglar to burgle the house. Open windows are simply something that puts your home somewhere up the yet to be created measurable, discoverable and refutable scale of vulnerability to theft. You can read an interesting post with a link to an even more interesting video on police capture houses in my own city of Nottingham - here. Information about the video can be found here.
Crime as opportunity theorists and the Crime Scientists who believe that this weird criminological notion of opportunity is a cause of crime are pseudo scholars and pseudo scientists chiefly because, whilst claiming to be either objective criminologists or else 'real' scientists, they blindly believe in their insular world of self-referential confirmation bias, anecdotes and ever more complex truisms dressed up as causal explanations. They have yet to establish a consistent definition of opportunity or guardianship. And they have yet to formulate a measurable and discoverable value for victim or target vulnerability that can be tested by empirical research.
In the absolutely final analysis, the RAT notion of crime opportunity is nothing more than an unhelpful truism. I'm afraid that I have to say that anyone claiming that such a notion of opportunity is a cause of crime is, unfortunately, a pseudoscientist supporter armed with a conveniently infinitely variable, untestable and therefore irrefutable post-hoc explanation for crime that ultimately is based on the illogical premise that all successfully completed crimes cause themselves to happen. Put another way, so called crime as opportunity theory is currently based on the premise that something you have not yet done is the cause of you doing it. If you are happy with this RAT-based crime as opportunity notion for crime causation, then - I don't wish to be rude but - might I suggest you set up your own church for those who believe in criminological miracles. Why not call it the Church of Crime Science? Alternatively you might wish to consider the above logical arguments, which explain why the current notion of crime opportunity is both unrealistically simplistic in part and is, elsewhere in its reasoning, completely impossible as a cause of crime.
OFFENDERS PLAY DICE
Crime as opportunity theory and Routine Activity Theory are wrong, because these theories are based on the premise that the characteristics of a criminal opportunity are certain. Yet only once a crime has been unsuccessfully attempted, or successfully completed, are its offender and guardianship characteristics certain. Only then does the opportunity relinquish all its uncertainty.
Not Quite Quantum Criminology: Proposing an Improved Definition of Criminal Opportunity
Unlike the predictions that can be made for physical laws such as gravity, criminal opportunities are not logically capable of being described as certainties. Rather, in this one respect at least, we should think of them as physicists think of quantum physics, Namely, that they exist as probabilities. With more research, we should be able to predict the probability of a particular property being successfully burgled, perhaps with the same precise accuracy, but not certainty, that a physicist can predict where particles will land (Wootters and Wojciech 1979) and casino bosses can predict that the house, overall, always wins. Here we would not be saying that any given premises will not be burgled, in the same way as a casino’s management cannot know for sure that you, the reader of this essay, will not win their jackpot. What we would be doing is predicting the likelihood of that premises, and others like it being burgled, which would be accurate at least until a new modus operandi and/or level of offender motivation influenced by market prices, and illicit demand and supply factors, bring significant change to the arms race between offenders and wider society. At which point it will be necessary to re-calculate the odds and then address the vulnerability of the premises and the motivation and abilities of potential offenders in order to reduce the victimisation risk.
Thinking about crime in this way enables us to propose a new definition of criminal opportunity:
A criminal opportunity comprises a juncture of circumstances, discovered or orchestrated by an offender, which they may perceive to be probably, but not certainly, favorable to the successful completion of a crime.
No definition should ever be mistaken as a hypothesis or a theory. Ratortunity provides us with an explanation that is based on a rule of thumb model that tells us essentially that offenders commit crimes because they can. That is no better at helping us to understand the causes of crime than old belief systems based on the idea that a witch or wizard must have done it. To understand how this is so David Deutsch has recorded an excellent lecture on good explanations in science. He teaches us that good explanations are difficult to vary and easy to refute, which is exactly the opposite of the infinitely variable and impossible to refute truism that is ratortunity.
I would like to thank Professor Ken Pease, Professor Graham Farrell and Professor Nick Tilley for kindly indulging me by debating and discussing the subject of this paper. While I remain open to any disconfirming evidence that the RAT notion of opportunity is wrong - to date in my opinion - nothing persuasive has yet been forthcoming.
Anderson, J. (2010). Australian Institute of Criminology. Research in Practice. Handbook No. 11. Bushfire Arson prevention Handbook. Australian Government. http://www.aic.gov.au/publications/current%20series/rip/1-10/11.aspx
Barthes, R. (1973) Mythologies. St Albans. Granada Publishing Ltd: Paladin.
Brantingham, P.L. and Brantingham. P. J. Environment, Routine, and Situation: Towards a Pattern Theory of Crime. In Clarke, R.V. and Felson, M. (eds) Advances in Criminological Theory. VOl. 5. New Brunswick. Transactions Publishers.
Clarke, R. V. (1984) Opportunity-Based Crime Rates: The Difficulties of Further Refinement. British Journal of Criminology. Vol. 24. No1. pp. 74-83
Clarke, R. V. and Mayhew, P. (1989) Crime as Opportunity: A Note on Domestic Gas Suicide in Britain and the Netherlands. British Journal of Criminology, Delinquency and Deviant Social Behaviour. 29:1. Winter. pp.35-46
Cohen, L. E. and Felson, M. (1979) Social change and crime rate trends: A routine activity approach. American Sociological Review, 44, 558-608.
Curtis. G.N.(undated) The Fallacy Files: http://www.fallacyfiles.org/ambiguit.html
Einstradtler, W. and Henry, S. (1995) Criminological Theory: An Analysis of Its Underlying Assumptions. Orlando. Harcourt Brace College Publishers.
Farrell, G. Phillips. C. and Pease, K. (1995) Like Taking Candy: Why Does Repeat Victimization Occur? British Journal of Criminology. Vol. 35. Summer. pp. 384-399
Farrell, G. Clark, K, Ellingworth, D. and Pease, K. (2005) OF TARGETS AND SUPERTARGETS: A ROUTINE ACTIVITY THEORY OF HIGH CRIME RATES. Internet Journal of Criminology.http://www.internetjournalofcriminology.com/Farrell,%20Clark,%20Ellingworth%20&%20Pease%20-%20Supertargets.pdf
Felson, M. and Clarke, R.V. (1998) Opportunity Makes the Thief. Paper No. 98. Police Research Series. London. Home Office.
Felson, M. (2002) Crime and Everyday Life (third Edition). London. Sage.
Felson, M. and Boba, R. (2010) Crime and Everyday Life. London. Sage
Felson, R. B. (1993) Predatory and Dispute-related Violence: A Social Interactionist Approach. In Clarke, R.V. and Felson, M. (eds) Advances in Criminological Theory. VOl. 5. New Brunswick. Transactions Publishers.
Garwood, J. (2011) A quasi-experimental investigation of self-reported offending and perception of criminal opportunity in undergraduate students. Security Journal. Vol. 24. 1. pp. 37-51.
James, W. (2008 – reprint) A Pluralistic Universe. Herbert Lectures at ManchesterCollege On the Present Situation in Philosophy. Maryland. ArcManor
Laycock, G. (2003). Launching Crime Science. Jill Dando Institute of Crime Science. University College London. ISBN 0-9545607-1-X http://www.ucl.ac.uk/jdi/downloads/publications/crime_science_short_reports/launching_crime_science.pdf
Note: Although it had been published and online by UCL since 2003, the above article by Professor Gloria Laycock has been, for some unknown reason, removed from the Internet - despite being cited by scholars at least six times according to Google's academic citation index. Anyone interested in the history of scientific theory formation and development, wishing to obtain the original pdf copy , may do so, I'm told, by emailing email@example.com
Maranda, P. (ed) (1972) Introducton. Mythology. Harmondsworth. Penguin Books.
Mayhew, P. Clarke, R. V. and Elliot, D. (1989) The Howard Journal of Criminal Justice Volume 28, Issue 1, pp.1–8.
Parke, R. L. 2000 Voodoo Science: The Road from Foolishness to Fraud. Oxford: Oxford University Press.
Pease, K, (2008). How to Behave Like a Scientist? Policing http://www-staff.lboro.ac.uk/~ssgf/KP/2008_Pease_Behaving_Badly.pdf
Popper, K. (1976). Unended quest: An intellectual autobiography. LaSalle, IL: Open Court.
Read, T., and N. Tilley (2000). Not Rocket Science? Problem–Solving and Crime Reduction. Crime Reduction Research Series. Paper No. 6. London: Home Office Policing and Reducing Crime Unit. http://www.popcenter.org/tools/implementing_responses/PDFs/Read.pdf
Sutton, M. (1998) Handling Stolen Goods and Theft: A Market Reduction Approach. Home Office Research Study 178. Home Office. London.
Sutton, M. (2010) Stolen Goods Markets. Problem Oriented Policing Guide No. 57. U.S.A. Department of Justice COPS Programme. (Peer reviewed international policing guide. http://www.popcenter.org/problems/stolen_goods/
Sutton, M (2012) Contingency Makes or Breaks the Thief: Introducing the Perception Contingency Process Hypothesis. Best Thinking.com
Tilley, N. (1993) After Kirkholt – Theory, Method and Results of Replication Evaluations. Crime Prevention Unit Series Paper N. 47. Home Office Police Research Group. London.
Tilley, N. and Laycock, G. (2002). Working out what to do: Evidence based crime reduction. Crime Reduction Series Paper 11. London Home Office https://www.ncjrs.gov/pdffiles1/nij/grants/193161.pdf
Young, J. (1994) Recent Paradigms in Criminology. In Maguire, M. , Morgan, R. and Reiner, R. (eds) The Oxford Handbook of Criminology, Oxford: Oxford University Press. pp. 69–124.
Wanjek, C, (2003) Bad Medicine: Misconceptions and Misuses Revealed, From Distance Healing to Vitamin O. Hoboken New Jersey, John Wiley and Sons.
Weaver, F.M. and Carroll, J. S. (1985) Crime Perceptions in a Natural Setting by Expert and Novice Shoplifters. Social Psychology Quarterly. Vol 48. No 4. 349-359.
Willison, R. (2000) Understanding and Addressing Criminal Opportunity: The Application of Situational Crime Prevention to IS Security. Journal of Financial Crime. Vol. 7. No. 3. pp 201-210.
Wootters, W. K. and Wojciech, H. Z. (1979) Complementarity in the double-slit experiment: quantum nonseperability and quantitative statement of Bohr’s principle. Physics Review D. Volume 19. Issue 2 p. 473-484
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