Police Methods | Section 4.1

Police Methods by Adam J. McKee

Section 4.1: Crime Science

The article below was written by Ronald V. Clarke & John E. Eck as part of a much larger work on this fascinating topic.



8. Use the problem analysis triangle

Most criminological theories focus on what makes people “criminal”. They find causes in distant factors, such as child-rearing practices, genetic makeup, and psychological or social processes. These theories are very difficult to test; are of varying and unknown scientific validity; and yield ambiguous policy implications that are mostly beyond the reach of police practice. But you will find that the theories and concepts of environmental criminology (and of the new discipline of crime science) are very helpful in everyday police work. This is because they deal with the immediate situational causes of crime events, including temptations and opportunities and inadequate protection of targets. You will be a stronger member of the problem-oriented team if you are familiar with these concepts.

The problem analysis triangle (also known as the crime triangle) comes from one of the main theories of environmental criminology – routine activity theory. This theory, originally formulated by Lawrence Cohen and Marcus Felson, states that predatory crime occurs when a likely offender and suitable target come together in time and place, without a capable guardian present. It takes the existence of a likely offender for granted since normal human greed and selfishness are sufficient explanations of most criminal motivation. It makes no distinction between a human victim and an inanimate target since both can meet the offender’s purpose. And it defines a capable guardian in terms of both human actors and security devices. This formulation led to the original problem analysis triangle with the three sides representing the offender, the target, and the location.

By directing attention to the three major components of any problem, the inner triangle helps to ensure that your analysis covers all three. Police are used to thinking about a problem in terms of the offenders involved – indeed, the usual focus is almost exclusively on how to identify and arrest them. But POP requires that you explore a broader range of factors and this requires information about the victims and the places involved.

The latest formulation of the problem analysis triangle adds an outer triangle of “controllers” for each of the three original elements:

      • For the target/victim, this is the capable guardian of the original formulation of routine activity theory – usually people protecting themselves, their own belongings or those of family members, friends, and co-workers. Guardians also include public police and private security.
      • For the offender, this is the handler, someone who knows the offender well and who is in a position to exert some control over his or her actions. Handlers include parents, siblings, teachers, friends and spouses. Probation and parole authorities often augment or substitute for normal handlers.
      • For the place, the controller is the manager, the owner or designee who has some responsibility for controlling behavior in the specific location such as a bus driver or teacher in a school, bar owners in drinking establishments, landlords in rental housing, or flight attendants on commercial airliners.

The problem analysis triangle is the basis for another useful analytic tool – a classification of the three main kinds of problems that confront police and a theory about how these problems arise. John Eck and William Spelman have proposed classifying such problems as “wolf,” “duck” and “den” problems:

      1. Repeat offending problems involve offenders attacking different targets at different places. These are ravenous WOLF problems. An armed robber who attacks a series of different banks is an example of a pure wolf problem. Wolf problems occur when offenders are able to locate temporarily vulnerable targets and places. The controllers for these targets and places may act to prevent future attacks, but the offenders move on to other targets and places. It is the lack of control by handlers that facilitates wolf problems.

      1. Repeat victimization problems involve victims repeatedly attacked by different offenders. These are sitting DUCK problems. Taxi drivers repeatedly robbed in different locations by different people is an example of a pure duck problem. Duck problems occur when victims continually interact with potential offenders at different places, but the victims do not increase their precautionary measures and their guardians are either absent or ineffective.

      1. Repeat location problems involve different offenders and different targets interacting at the same place. These are DEN of iniquity problems. A drinking establishment that has many fights, but always among different people, is an example of a pure den problem. Den problems occur when new potential offenders and new potential targets encounter each other in a place where management is ineffective. The setting continues to facilitate the problem events.

Note that pure wolf, duck, and den problems are rare. Most problems involve a mixture. The question is, which is most dominant in a given problem: wolves, ducks, or dens?

When crime is occurring, all inner elements of the triangle must be present and all outer elements weak or absent. If potential offenders are constantly present, for example, but crimes occur only when guardians are absent, then rescheduling guardians might be a useful solution. Ask yourself, “What does the problem analysis triangle look like before, during, and after crimes?”

Understanding how problems are created by opportunities will help you think about what might be done to: prevent offenders from reoffending by making better use of handlers; help victims reduce their probabilities of being targets; and to change places where problems occur, be these schools, taverns, or parking lots. In short, right from the beginning, it helps you to focus data collection on those six aspects most likely to lead to practical solutions.

9. Know that opportunity makes the thief

For environmental criminologists, “opportunity makes the thief” is more than just a popular saying; it is the cornerstone of their approach. They believe that if opportunity increases so will crime. To see if you agree, consider the scenario suggested by Gloria Laycock and Nick Tilley of the Jill Dando Institute of Crime Science:

“Suppose all situational controls were to be abandoned: no locks, no custom controls, cash left for parking in an open pot for occasional collection, no library check-outs, no baggage screening at airports, no ticket checks at train stations, no traffic lights, etc., would there be no change in the volume of crime and disorder?”

If you answer that of course crime and disorder would increase, then you, too, think opportunity is a cause of crime. Incredibly, most criminologists would not agree. They believe that opportunity can only determine when and where crime occurs, not whether it occurs. In their view, whether crime occurs is wholly dependent on offenders’ propensities and these propensities collectively determine the volume of crime in society.

In fact, crime levels are as much determined by the opportunities afforded by the physical and social arrangements of society as by the attitudes and dispositions of the population. This is difficult to prove without conducting experiments, but it would be unethical to create new opportunities for burglary or robbery and wait to see what happens. However, experiments have been undertaken with minor transgressions. In the 1920s, researchers gave children the opportunity to cheat on tests, to lie about cheating, and to steal coins from puzzles used. Other researchers have scattered stamped and addressed letters in the streets, some containing money, to see if these were mailed. In a third group of lab experiments, subjects were instructed to “punish” others for disobeying test instructions by delivering severe electric shocks through the test apparatus. (In fact, no shocks were actually delivered).

The results of these experiments support the causal role of opportunity. Most of the subjects, even those who generally resisted temptation, took some opportunities to behave dishonestly or aggressively – opportunities they would not have encountered but for their participation in the studies. But you cannot generalize from these minor transgressions to crimes of robbery or car theft. We, therefore, must turn to some other sources of evidence about the importance of opportunity in causing crime.

Suicide and opportunity.

Suicide is not a crime, but like much crime is generally thought to be deeply motivated. However, there is clear evidence from the U.K. that opportunity plays an important part in suicide. During the 1950s, about half the people who killed themselves in the U.K. used domestic gas, which contained lethal amounts of carbon monoxide (CO). This was known as “putting your head in the gas oven.” In the 1960s, gas began to be made from oil instead of coal. The new gas had less CO and the number of gas suicides began to decline. By 1968, only about 20 percent of suicides involved gas. This is when a second change began: manufactured gas was replaced by natural gas from the North Sea. Natural gas contains no CO and is almost impossible to use for suicide. By the mid-1970s, less than 1 percent of suicides in the U.K. used this method.

What is deeply surprising is that suicides did not displace wholesale to other methods. The table shows that between 1958 and 1976 suicides dropped by nearly 30 percent from 5,298 to 3,816. (This was during an economic decline when suicide could have been expected to increase and, indeed, was increasing in other European countries.) People did not turn to other methods because these all had drawbacks. Overdoses are much less lethal than carbon monoxide. Hanging requires more knowledge as well as courage. Not everyone has access to guns, which can result in disfigurement instead of death. On the other hand, domestic gas was readily available in most homes. It was highly lethal and using it was bloodless and painless. It is not surprising it was the preferred method for so long and that when the opportunity to use it was removed, the number of suicides declined.

Understanding the arguments in this section, and accepting that opportunity causes crime, does not mean you must deny the importance of other causes, such as inherited personalities, broken homes, and inconsistent discipline. But there is little you can do to change people’s personalities or the divorce rate or poor parenting. However, you can alter the criminogenic situations in which they find themselves. Understanding that opportunity makes the thief will help direct your attention to practical means of preventing crime, and help you defend them from criticism.

Murder and opportunity.

Opportunity also plays an important causal role in murder, as shown by a comparison made some years ago of homicide rates in the United States and the U.K. For 1980-84, the period covered by the study, the overall homicide rate in this country was 8.5 times greater than in England and Wales. The gun homicide and handgun homicide rates were, respectively, 63 times and 75 times as great. In the whole of England and Wales in this period (with about 50 million people), only 57 handgun murders occurred. In the United States, with a population of about 230 million (less than five times greater) a total of 46,553 people were murdered with a handgun.

These findings tended to be dismissed because the overall crime rate in the U.S. was generally higher than it was in England and Wales during that period. However, in the past 15 years the overall crime rates of the two countries have converged so that there is now little difference between them, with the glaring exception of homicide. There is still a much higher rate of murder in this country because far more people here own guns, especially handguns, than in the U.K. Even the police in the U.K. do not routinely carry guns! So, when people fight here, someone is much more likely to get shot than in the U.K. Similar, but not such striking findings, emerge from comparing murder rates in the U.S. and Canada (see box). Taken together, these comparisons show that gun availability (an opportunity variable) plays an important causal role in murder.

Understanding the arguments in this section, and accepting that opportunity causes crime, does not mean you must deny the importance of other causes, such as inherited personalities, broken homes, and inconsistent discipline. But there is little you can do to change people’s personalities or the divorce rate or poor parenting. However, you can alter the criminogenic situations in which they find themselves. Understanding that opportunity makes the thief will help direct your attention to practical means of preventing crime, and help you defend them from criticism.

10. Put yourself in the offender’s shoes

Whenever you analyze a crime problem or think about solutions, try to see the crime from the offender’s perspective. Try to understand why they commit the crime – not the distant social or psychological causes, but the benefits they are seeking. A radical critique of criminology pointed out 30 years ago that is not their genes that propel bank robbers through the doors of the bank: they rob banks because they want to get rich.

In many cases of theft and robbery the benefits are obvious, but they may not be clear for gang violence or so-called “senseless” vandalism and graffiti. In fact, graffiti can mark the territory of a juvenile gang, can indicate where to purchase drugs, or can simply be a way to show off. Knowing which of these reasons is dominant helps to define the focus of a problem-solving project and unravel the contributory factors. It can also help the project team identify solutions. Thus, the New York City subway authorities succeeded in eradicating graffiti only when they understood the motivation of the “taggers,” which was to see their handiwork on display as the trains traveled around the system (see Step 41).

Learning how offenders commit crimes is as important as learning why they commit them. You will find rational choice theory helpful in thinking about these questions. The name is misleading because the theory does not assume that offenders plan their crimes carefully; it assumes only that they are seeking to benefit themselves by their crimes, which is rational enough. The theory does not even assume that offenders succeed in obtaining the benefits they seek. This is because they rarely have all the information they need, they do not devote enough time to planning their actions, they take risks, and they make mistakes. This is how we all behave in everyday decisionmaking and is what theorists call limited or bounded rationality.

Offenders must often decide quickly how to accomplish their goals and how to get away without being caught. Interviewing offenders will help you understand how they make these decisions. Surprisingly, it is usually not difficult to get offenders to talk, especially if you confine yourself to the general nature of the problem you are trying to solve, and avoid specific questions about crimes they have committed. Offenders are no exception to the rule that we enjoy talking about ourselves and about the work we do. On the other hand, always retain some skepticism as people who habitually break the law may also habitually exaggerate and lie.

If you cannot interview offenders, try to imagine the course of a crime (see Step 35). What must be done at each stage? How are targets selected? How can victims be subdued or tricked? The police escaped? The goods disposed of? Even if you cannot answer all these questions about modus operandi, your attempt to enter the offender’s mind can help you think about responses. This is not an invitation to try your hand at psychoanalysis. Instead of delving into the offender’s unconscious you should try to understand the tangible benefits the offender is seeking and how he must manage the commission of crime without too much effort or risk. This is what Paul Ekblom of the Home Office Research Department means when he advises problem solvers to “think thief.”

Another alternative to interviewing your own group of offenders is to search the literature for reports of interviews with similar groups of offenders. Environmental criminologists have greatly expanded our knowledge about the methods that criminals use by interviewing car thieves, muggers, shoplifters, and residential and commercial burglars. The offenders may not be quite the same group as your own, but carefully looking at the results of these interview studies can suggest hypotheses that you might explore in regard to your own problem.

11. Expect offenders to react

Offenders make choices based on their perceptions of opportunities. Understanding how offenders see things is important to preventing crime because almost all crime prevention involves changing offenders’ perceptions of crime opportunities. Some prevention programs work directly on offenders’ perceptions, as when police inform offenders that they are being closely watched. But most prevention schemes work through one or more intermediate steps, as in property marking schemes, for example, where residents apply window stickers showing participation. Changes in the environment change offender perceptions. These perceptions influence offenders’ behaviors that, in turn, alter crime patterns.

In many cases, the preventive measures deter offenders from further criminal activity. They can also have the positive unintended effects of: (1) reducing crime beyond the focus of the measures, which is known as diffusion of benefits (see Steps 13 and 47); and (2) reducing crime before they have actually been implemented, known as anticipatory benefits (Step 52). However, preventive measures do not always achieve the desired effects, sometimes because offenders are quite unaware of the interventions in place. For example, offenders may continue to offend in the face of covert enforcement because they might not perceive that their risks of being caught have increased. In other cases, offenders may adjust negatively to the preventive measures. These negative adjustments include displacement and long-term adaptation.

Displacement occurs when offenders change their behavior to thwart preventive actions. Displacement is the opposite of diffusion of benefits. Displacement is a possible threat, but it is far from inevitable. Reviews show that many situational prevention programs show little or no evidence of displacement, and when displacement is found, it seldom fully offsets the prevention benefits (Step 12).

Adaptation refers to a longer term process whereby the offender population as a whole discovers new crime vulnerabilities after preventive measures have been in place for a while. Paul Ekblom, Ken Pease, and other researchers often use the analogy of an arms race between preventers and offenders when discussing this process. So, in time, we can expect many crimes that have been reduced by preventive measures to reappear as criminals discover new ways to commit them. Adaptation may occur as the original offenders slowly discover new methods, or it may occur as new offenders take advantage of changing opportunities.

A good example of adaptation is credit card fraud. Another more recent example of adaptation involves bike locks. Bike thieves discovered that they could defeat a widely used and effective lock by using a common and cheap ballpoint pen. But not all preventive measures are so vulnerable to criminal ingenuity. For example, Neal Shover has argued that technology has brought a lasting respite from safecracking, which is now very rare though it was once quite common.

12. Don’t be discouraged by the displacement doomsters

Problem-oriented policing often tries to reduce opportunities for crime. For example, window locks may be fitted to prevent burglary in an apartment complex, or closed-circuit television cameras installed to prevent thefts in parking lots. These ways of reducing opportunities for crime often meet the same objection: all they do is move crime around, not prevent it. This theory of displacement sees crime as being shifted around in five main ways:

      1. Crime is moved from one place to another (geographical).
      2. Crime is moved from one time to another (temporal). 
      3. Crime is directed away from one target to another (target). 
      4. One method of committing crime replaces another (tactical). 
      5. One kind of crime is substituted for another (crime type).

In each case, the theory assumes that offenders are compelled to commit crime, whatever impediments they face. The basis for the assumption is either that the propensity to commit crime builds up and must be discharged in the same way that sexual release is sought, or that “professional” criminals or drug addicts must obtain a certain income from crime to maintain their lifestyles. There is no evidence that offenders must satiate some deep physiological appetite to commit crimes. In fact, there is plenty of evidence that people make choices about whether, where, and when to offend. Whatever its basis, the displacement assumption neglects the important role of temptation and opportunity in crime (Step 9).

Even in the case of more committed offenders, the displacement theory fails to give enough importance to opportunity. Thus, research on drug addicts has shown that they adapt to variations in the supply of drugs. Nor is there any simple progression in drug use. Rather, addicts might be forced to use smaller amounts or less agreeable drugs because the supply of drugs has been cut.

As for professional criminals like bank robbers, there is no reason to assume that they must obtain a fixed amount of money from crime. They would surely commit fewer robberies if these became difficult and risky, just as they would commit more robberies if these became easy. Bank robbers, like everyone else, may sometimes have to adjust to reduced circumstances and be content with lower levels of income.

This does not mean that we can ignore displacement. Indeed, rational choice theory predicts that offenders will displace when the benefits for doing so outweigh the costs. For example, in the early 1990s the New York City Police deployed its Tactical Narcotics Teams to several high drug-dealing neighborhoods. Dealers responded by shifting their sales locations from curbside to inside the foyers of apartment buildings. But numerous other studies have found that displacement did not occur at all, or only to a limited extent. For example:

      • Intensive gun patrols reduced firearms crimes in a Kansas City, Missouri high gun-crime neighborhood without displacing these or other crimes to nearby communities
      • New identification procedures greatly reduced check frauds in Sweden, with no evidence of displacement to a range of “conceivable” alternative crimes
      • Extensive target hardening undertaken in banks in Australia lowered robbery rates, but there was no sign that corner stores, gas stations, betting shops, motels, or people in the street began to experience more robberies
      • Burglary was not displaced to nearby apartment complexes when a problem-solving approach drove down burglary in a high-crime apartment complex in Newport News, Virginia.
      • When streets were closed in the London neighborhood of Finsbury Park and policing was intensified, there was little evidence that prostitutes simply moved to other nearby locations. According to the researchers, many of the women working the streets in Finsbury Park were not deeply committed to prostitution, but saw it as a relatively easy way to make a living. When conditions changed so did their involvement and many seem to have given up “the game” (Step 50).
      • Redesign of a trolley stop to curb robberies and assaults resulted in a reduction in violent crime at a San Diego, California location without shifting these crimes to other trolley stops
      • In these examples and numerous others, the offenders’ costs of displacing seemed to have outweighed the benefits and the examples bear out the argument that displacement occurs much less than commonly believed. This is the consensus of four different reviews of the displacement literature undertaken in the United Kingdom, Canada, the United States, and The Netherlands. The Dutch review (the most recent one) reports that in 22 of 55 studies from around the world in which displacement was examined, no evidence of it was found. In the remaining 33 studies, in which evidence of displacement was found, only some of the crime seems to have been displaced. In no case was the amount of crime displaced equal to the amount prevented. And in no case did displacement increase crime.
      • Displacement is usually limited because offenders have difficulty adapting quickly. If they do make changes they are most likely to change to places, times, targets, methods, and crime types that are similar to those the prevention program blocks because these are the easiest changes for them to make. This suggests that displacement can be predicted by anticipating the easiest changes for offenders to make. If there are obvious easy changes, then you should consider how to incorporate these in your prevention plan. And if you cannot include them, then you should consider monitoring them to detect possible displacement.
      • To sum up, displacement is always a threat, but there are strong theoretical reasons for believing that it is far from inevitable. In addition, the studies of displacement show that even when it does occur, it may be far from complete and that important net reductions in crime can be achieved by opportunity-reducing measures


Source:   COP Office.  Crime Analysis for Problem Solvers In 60 Small Steps.



Modification History

File Created:  08/10/2019

Last Modified:  08/13/2019

[ Back | Content | Next]

This work is licensed under an Open Educational Resource-Quality Master Source (OER-QMS) License.

Open Education Resource--Quality Master Source License


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.