Expressive and Instrumental Offending

Abstract

Although previous research into specialisation has been dominated by the debate over the existence of specialisation versus versatility, it is suggested that research needs to move beyond the restrictions of this dispute. The current study explores the criminal careers of 200 offenders based on their criminal records, obtained from a police database in the North West of England, aiming to understand the patterns and nature of specialisation by determining the presence of differentiation within their general offending behaviours and examining whether the framework of Expressive and Instrumental offending styles can account for any specialised tendencies that emerge. Fifty-eight offences were subjected to Smallest Space Analysis. Results revealed that a model of criminal differentiation could be identified and that any specialisation is represented in terms of Expressive and Instrumental offending styles.

Keywords

specialisation differentiation criminal careers expressive offending behaviour instrumental offending behaviour

For over 150 years, the study of criminal careers has generated a wealth of knowledge regarding the longitudinal patterning of criminal activity investigating how and why criminal behaviour begins, develops over time and ends. One of the main reasons for studying the criminal career of offenders is that it provides us with crucial information regarding the patterns of offending behaviour over time, which has direct implications for decision making in the criminal justice system (Piquero, Farrington, & Blumstein, 2007). Within the literature, there are four main dimensions that are typically explored in the sequence of offences that construct a criminal career: participation (the distinction between those who commit crimes and those who do not); frequency (the rate of criminal activity among offenders); crime type mix that includes seriousness, escalation, and specialisation; and finally career length (length of time an offender is criminally active; Piquero & Mazerolle, 2001). Youngs (2001) developed the notion of specialisation, identifying three components: Differentiation, Repetition, and Exclusivity of behaviour. She argues that some degree of each of these within offending behaviour is necessary to support the specialisation hypothesis. The focus of the present study is the Differentiation component.

Criminal career research has also direct implications for the development of a scientific basis for offender profiling. The fundamental assumption at the heart of offender profiling involves establishing whether offenders are consistent from one crime to another, by considering an offender’s crimes and comparing them with other offences, and how offenders can be distinguished from one another (Canter, 2004). Integral to this is the debate within criminal career research about whether offenders are typically specialist or versatile. If offenders specialise in their criminal careers, then this will allow for inferences to be developed regarding not only their past offences but also the offences they are likely to commit in the future.

Are Criminals Specialised or Versatile in Their Offending Behaviour?

This is a question that has divided research for over half a century. Specialisation generally means that an offender will persistently commit similar offences throughout the course of their offending career. These patterns can be both “strict” whereby an offender continually commits a specific offence, or ‘clustered’ where the offender will commit similar types of offences, such as theft (Delisi, 2003; Weiner, 1989). Individuals can vary from the ‘specialist’ who will primarily either engage in one type of offence or a group of analogous offences, to ‘generalists’ who engage in a wide variety of offences throughout their offending histories (Williams & Arnold, 2002).

Although some researchers dismiss the idea of specialisation, asserting that ‘in spite of years of tireless research motivated by the belief in specialisation, no credible evidence has been reported’ (Gottfredson & Hirschi, 1990, p. 91) this is at odds with the contention that ‘offenders are much more likely to repeat the same than to switch offences’ (Britt, 1996, p.219).

It appears that a general confusion over the question of the existence of specialisation has resulted in a lack of understanding as to the nature of specialisation and has ultimately clouded the fundamental components of the issue (Youngs, 2001) making it therefore important to reconcile the paradox of specialisation and versatility (McGloin, Sullivan & Piquero, 2009) and shed some light on this dispute.

It is evident that two distinct theoretical frameworks guide the study of criminal careers. The first, exemplified by Gottfredson and Hirschi’s (1990) general theory of crime posits that offending is a product of low self-control, therefore, opportunistic. According to them, persons with low self-control are expected to be more prone to criminal behaviour than persons with high self-control. These individuals tend to opt for behaviours yielding immediate rewards without considering long-term negative consequences. Individuals with little self-control are likely to participate in any crime that requires minimal planning due to impulsivity and opportunity, given the opportunity that all offenders are equally versatile (Nieuwbeerta, Blokland, Piquero, & Sweeten, 2011). Any appearance of specialisation is more the product of opportunities to commit the same crime rather than a specific attraction to specific types of crime (Osgood & Schreck, 2007). Social-bond theory, which focuses on the importance of attachment, commitment, and involvement in society, also suggests that offenders commit crimes due to low levels of social control thus being versatile (Tumminello, Edling, Liljeros, Mantegna, & Sarnecki, 2013).

Studies of general offender populations contend that the majority of offenders demonstrate a high proportion of versatility in their criminal careers (Britt, 1994; Chaiken & Chaiken, 1982; DeLisi & Piquero, 2011; Hindelang, 1971; Klein, 1984; Simon, 1997). The early work of Wolfgang, Figlio, and Sellin (1972) into the transition probabilities of 9,945 boys in a Philadelphia birth cohort set the precedent for research concerning specialisation in offending behaviour and found insufficient evidence for the specialist offender. A meta-analysis of 33 studies exploring specialisation found that only four displayed any evidence of specialisation (Klein, 1984). This finding was supported by Peterson and Braiker (1980) and Simon (1997) who discovered that half of all inmates surveyed claimed to have committed at least four different types of crime during the 3 years before their incarceration. However, all of the studies in the Klein analysis were of juvenile offenders, while it has been observed that the weakest evidence of specialisation does tend to occur in samples of juveniles (Bursik, 1980; Cohen, 1986; Nevares, Wolfgang, & Tracy, 1990). When studies have found support for specialised offending in juvenile samples, it has been limited to a small number of property theft and status offences (Armstrong & Britt, 2004). Overall, there has been insufficient evidence of specialisation within samples of juveniles (Armstrong & Britt, 2004; Bursik, 1980; Osgood & Schreck, 2007; Rojek & Erickson, 1982).

Conversely, regardless of the evidence opposing specialisation, there is a certain assumption implicit within some theories and crime typologies that presumes specialisation exists. Moffitt (1993) rejected the idea of one general theory of crime, suggesting that variations within offending occur due to variations within offenders, showing the existence of two distinct subgroups of offending. He distinguishes life-course persistent from adolescence-limited offenders, hypothesising that the former shows a more diverse pattern of offending compared with the latter. Adolescent-limited offenders usually commit minor offences, as a result of their impaired attachment histories and troubled childhoods, while life-course persistent offenders commit serious and violent offences (Moffitt, 1993). Within-individual specialisation is also central to the work of Spelman (1994) who offered a learning hypothesis arguing that as offenders accumulate experience and knowledge in terms of the outcomes of their offences, they will tend to repeat acts that provide rewards refraining from acts that have a high likelihood of detection and risk involved. Therefore, as offenders age, they learn to repeat the same type of crime.

Soothill, Fitzpatrick, and Francis (2009) argued that specialisation is associated with the issue of whether it is possible to classify certain offenders into groups or “types,” which are defined by their preferred or “specialist” behaviour. He also highlights that researchers studying particular types of offending such as homicide have had no doubt as to the existence of specialised offending behaviour. For example, the concept of the “serial killer” is often tied up with certain assumptions regarding specialisation. The subculture of violence theory proposed by Wolfgang and Ferracutti (1967) also focused on the specificity of offending, particularly the specialisation in violence. There have been results that not only highlight the existence of specialisation but also indicate that it is more likely to be observed within unique crime categories (Trojan & Salfati, 2010), therefore specialisation may be offence specific.

Blumstein, Cohen, Das, and Moitra (1988) found that drug and car crime offences tended to be highly specialised offences, and property offences seemed to show a greater degree of specialisation than violent offences. But a substantial amount of work has also established specialists within violent crime (P. Brennan, Mednick, & John, 1989; Britt, 1996; Deane, Armstrong, & Felson, 2005; Lattimore, Visher, & Linster 1994; Lynam, Moffitt, & Piquero, 2004; Moffitt, Mednick, & Gabrielli, 1989; Osgood & Schreck, 2007). There appears to be mixed results concerning violent specialisation, as Stattin and Magnusson (1991) and Piquero (2000) found violent crimes to be the least specialised. Adams and Pizarro (2014) studied specialisation in the criminal careers of gang and non-gang homicide offenders and found that the homicide offenders in the sample were generally versatile in their offending leading up to the homicide while some evidence of specialisation was found with drug offences having the highest probability of occurring prior to the homicide incidents.

Although Lussier, Le Blanc, and Proulx (2005) discovered that rapists and child molesters showed divergence in their offending histories, with the latter exhibiting more specialised tendencies, Stander, Farrington, Hill, and Altham (1989) found that it was sexual offenders who were the most specialised. A high degree of offender consistency in serial stranger sex offenders was also found in the study by Deslauriers-Varin and Beauregard (2013). While Rojek and Erickson (1982) found evidence of specialisation for property offences and status offences, there was little indication of any specialisation within the other offence types in their sample. Repeated involvement has also been found in robbery and burglary (Bursik, 1980; Farrington, Snyder, & Finnegan, 1988; Petersilia, 1980; Smith & Smith, 1984; Yokota & Canter, 2004).

It is rare within the specialisation literature to find two studies with similar categorisation of offences (Williams & Arnold, 2002), which not only makes the comparison with similar research difficult but it also highlights the problems of putting offenders into “types.” Static typologies do not fully capture the reality of the criminal career (Francis, Soothill, & Fligelstone, 2004), which is dynamic in nature. Canter and Youngs (2009) proposed that it would be more beneficial to think along the lines of “themes” rather than distinct types. Sullivan, McGloin, Pratt, and Piquero (2006) suggested that research that adopts a finer lens and disaggregates within offender labels tends to indicate a higher proportion of specialisation. Therefore, it might be reasonably argued that although an offender rarely commits the same offences successively, most of the crimes committed by the offender might be of the same nature. In fact, when specialisation was redefined, Bursik (1980) found evidence of some specialisation tendencies.

It is possible that a number of factors influence whether a picture of offending specialisation emerges, as previously noted research into the area of specialisation has been limited in particular by methodological problems. Kempf (1987) proposed that the results of previous investigations of specialisation must be interpreted with caution and should not be viewed as conclusive due to the problems that exist particularly in the areas of crime category specification, portion of career examined, and method of measurement.

It appears that different studies report different degrees of specialisation, perhaps due to the different definitions given to specialisation (see Blumstein, Cohen, Roth, & Visher, 1986; Paternoster, Brame, Piquero, Mazerolle, & Dean, 1998; Williams & Arnold, 2002). These definitions are different in the emphasis to either “specific” offences or offences types. For instance, does an offender specialise in burglary? Or, does this offender specialise within burglary by specifically ignoring the break in of residential houses and focusing on non-dwellings such as shops? (Soothill et al., 2009).

The method of measurement used by many studies of specialisation adopts a sequential approach which is rather limited in its ability to find evidence of specialisation; it focuses only on the similarity between adjoining offences, and ignores the useful information regarding the similarities between other offences that have occurred over the course of the criminal career (Osgood & Schreck, 2007). If consecutive arrests for the same offence are interpreted as evidence of specialisation, then is an offender still considered specialist if his or her arrests 8 through 11 are for theft, but arrests 1 through 7 are not? (Delisi, 2003). Osgood and Schreck (2007) further noted that sequential analysis will tend to find specialisation with the pattern “robbery-robbery-burglary” but not in the very similar offence pattern of “robbery-burglary-robbery.” This approach to understanding specialisation is unrealistic and does not appreciate the dynamic nature of offending, while neglecting a wealth of research that has suggested that when taking a broader perspective specialisation is more evident (Sullivan et al., 2006). When Sullivan et al. (2006) took a step back from their data and looked at the overall patterns of offending, they found that the results undoubtedly suggested specialisation more than versatility.

This leads to the idea that offenders may display specialisation tendencies over time, which sequential methods are unable to uncover. Research does indicate that offenders will display a stronger tendency to switch between offence types within the same cluster of offence types such as violence and property, and a weaker tendency to switch to offences outside a cluster. Therefore, it may be the case that rather than specific forms of specialisation, offenders tend to specialise within certain clusters of offences, a concept that would be missed within many of the studies in the current literature.

A rather significant limitation of the criminal career framework regarding specialisation is the fact that a great deal of the research only involves juvenile samples making it difficult to generalise these findings to adult offending populations. Indeed, many of the studies also limit the number of offences within the “career.” For example, the Philadelphia birth cohort study only traced the careers of delinquents to the ninth offence. It is more than likely that some careers are likely to extend beyond this restriction. Moreover, Gottfredson and Hirschi’s (1990) rejection of specialisation appears to be based on the results from surveys of offenders conducted by the RAND Corporation, while these surveys restrict the recall period to 3 years, from which generalisation to the entire criminal career is very likely to be problematic (Kempf, 1987). Indeed, this is also at odds with the large amount of research, which has suggested that specialisation increases as the career progresses (Blumstein et al., 1986, 1988; Bursik, 1980; DeLisi et al., 2011; Farrington, 1992; Lussier, 2005; Simon, 1997; Tumminello et al., 2013). In their study of 4,565 offenders, Williams and Arnold (2002) highlighted this point finding that specialisation tends to occur during the latter part of delinquent careers. In a study that examined the course of specialisation and versatility with maturation findings revealed that specialisation develops in a non-random manner suggesting that specialisation trends may be attributed to offenders who persist in crime rather than those who desist from it (Yonai, Levine, & Glicksohn, 2013). Nieuwbeerta et al. (2011) examined levels of diversity and changes in diversity over time across offending trajectories over the life span and found much diversity in general. When focusing on frequent offenders, high diversity was again the most common pattern during adulthood followed by a pattern of specialisation; when offenders specialised during adulthood, it was mainly toward property crimes. These studies highlight the fact that specialisation can vary in terms of the stage of the criminal career; therefore, unless the entire career is followed, research results are needlessly restricted.

Moving Beyond the Debate: Toward a Model of Specialised Offending Styles

Taking into account the above limitations, it is clear that research has yet to arrive at a clear understanding of the nature of specialisation. It is apparent that what is missing is an understanding of the processes that underlie and develop the patterns, which seem to be apparent in specialised offending (Guerette, Stenius, & McGloin, 2005; Youngs, 2001) and an established theoretical framework which the researcher can draw on in developing such ideas. It may be the case that rather than specific forms of specialisation, offenders tend to specialise within certain clusters of offences that are similar thematically, so by examining broader groupings of offences, it may be possible to develop an underlying theoretical construct based on the clusters or “themes” that the offences display.

To understand how this approach differs from previous studies into specialised offending, consider the example of an offender with previous arrests for theft, sexual assault, and fraud. According to “traditional” assumptions of specialisation, these would be considered crimes of a versatile offender, but as a matter of fact, these crimes are thematically similar as they all offer the offender instrumental gain (Trojan & Salfati, 2010) and can be interpreted in terms of how they are associated thematically with the other offences in the criminal history. The central trust of this approach implies that there will be dominant themes emerging in offending behaviour. The thematic approach is not, in the case of criminal careers, concerned with whether an individual offence is either expressive or instrumental, but rather how we understand the co-occurrences of groups of offences across the offending backgrounds. This approach has been increasingly used to better conceptualise offending behaviours, crime scene actions and offender characteristics in homicide, arson, rape, and burglary, to name a few (Bateman & Salfati, 2007; Canter & Fritzon, 1998; Canter & Heritage, 1990; Salfati, 2000; Santtila, Hakkanen, Canter, & Elfgren, 2003). However, it only recently begun to be used to examine the degree of specialisation in offender’s criminal histories with regard to expressive and instrumental themes.

Feshbach (1964) was the first to propose a theoretical distinction between instrumental and expressive behaviours, claiming that this distinction was fundamental for understanding aggression. He suggested that there are two separate forms of aggression: hostile or expressive and instrumental aggression, which are distinguished by the goals or rewards that they offer the offender. The expressive type of aggression is said to occur in response to an anger-inducing situation, such as a physical attack, insults, or even personal failures. The goal here is to make the victim of the offence suffer; therefore, it is motivated by a desire to actually harm or injure in some way a desired object (Santtila et al., 2003). In addition, it has been characterised as both impulsive and uncontrolled, and can thus be interpreted as an emotional response; these behaviours may be understood then as direct expressions of a goal or need. Instrumental aggression is motivated by the desire for objects or the status possessed by another person, such as money and territory. Therefore, instrumental aggression may occur when individuals attempt to achieve these goals and someone prevents them. It is important to note that these kinds of behaviours are not carried out for their own rewards, but to achieve some ulterior motive, which is external to the act of aggression. The different meanings that offending behaviours have to the offender during the crime can also be related to the interpersonal transaction between the offender and the victim, so for the expressive offence, the victim is suggested to represent a person onto whom the aggression is impulsively and aggressively vented out, while in the case of an instrumental offender, the victim in many ways is unimportant and just a target to the offender’s secondary motive (Salfati, 2000; Salfati & Haratsis, 2001).

The instrumental-expressive dimension is not without its critics. R. B. Felson (1993) and Tedeschi and Felson (1994) deviated from this distinction arguing instead that all violence is goal-oriented and that expressive violence does not exist. Even expressive acts of violence done in anger reflect an instrumental reaction to perceived wrongdoing. Regarding violence as always instrumental behaviour that is governed by rational choice and chosen on the grounds that some kind of “gain” is involved can be problematic as it overlooks how goal-oriented violence provides gratification for perpetrators, in many instances without calculation of cost and gain, but motivated by emotions (Canter & Ioannou, 2004a), “thrills,” “missions” (Katz, 1988), and so on, evident not only in many forms of criminal activity but also in collective violence.

The fact that this distinction has been widely acknowledged in an array of research (Fritzon, 2000; Miethe & Drass, 1999; Ressler, Douglas, & Burgess, 1995; Salfati, 2000; Salfati & Canter, 1999) suggests that this may be a useful distinction for differentiating offenders. However, most of the research in this area has focused on distinctions within offences such as homicide and sexual offences, which makes it difficult to generalise the findings to all offenders.

In a study of criminal weapon use, Lobato (2000) identified that offenders could be differentiated in terms of expressive and instrumental offending styles. Findings showed that for offenders exhibiting an Expressive offending style the weapon carried an emotional meaning, being an expression of the offender’s desire to inflict pain and make the victim suffer. The relationship between the emotional meaning of the weapon and expressive types of crime was found in offences such as murder, rape, indecent assault, and bodily harm. For those offenders exhibiting an Instrumental offending style, the weapon carried a criminality meaning, where the weapon was used to facilitate a crime. These offenders tended to commit instrumental offences such as embezzlement, drugs trafficking, robbery, and burglary; therefore, the aim in committing these crimes is to obtain desired objects. “This lends support to the feasibility that there is a class of crimes associated with instrumental and expressive offending behaviour. This may be seen as a broadening of Feshbach’s perspective on aggressive crimes to crimes in general” (Lobato, 2000, p. 125).

The notion of broadening the instrumental and expressive offending styles to a variety of crimes was supported by Youngs (2004) who found that two modes of operation were distinguished in her sample of 207 young offenders, the expressive and instrumental types of offences. In the expressive offences, the primary aim was the execution of the particular act itself. The behaviours were carried for rewards of their own thus highlighting the expressive and emotional nature of the offence. On the contrary, Instrumental offences were carried out not for their own rewards but to achieve some secondary goal. Therefore, this leads us to the notion that if offenders are specialised in their offending behaviour this may be represented in terms of expressive and instrumental aspects of their offending styles as these appear to be dominant themes within all offending behaviours.

Consequently, it may be possible to develop a theory of specialisation based on these core dimensions. What is interesting here is that the person property distinction implicit within the expressive and instrumental themes has been well documented within the specialisation literature (Blumstein et al., 1988; P. Brennan et al., 1989; Bursik, 1980; Cohen, 1986; Kempf, 1987; Rojek & Erickson, 1982). This lends support to the notion that there are a class of crimes associated with expressive and instrumental offending. More recently, there have been two studies that have endeavoured to place specialisation within a theory of expressive and instrumental offending styles. Trojan and Salfati (under review) examined the criminal careers of single-victim homicide offenders, and found that when considering the convictions in terms of their co-occurrences the offences could be grouped into two broad themes of Expressive and Instrumental offending. The instrumental offences consisted of property type offences such as theft and burglary and also fraud and legal offences. Expressive offences included offences that involved direct violence against a victim, such as assault and domestic violence and also violence against property such as criminal damage. Trojan and Salfati (2010) replicated this study comparing the single-victim homicide offenders with serial offenders with similar findings.

The present study explores the criminal careers of offenders to better understand the patterns and nature of specialisation. The first aim of the study is to determine the presence of specialisation within the general offending behaviours of the sample. The second aim of the study is to determine whether the framework of Expressive and Instrumental offending styles can account for any specialised tendencies that emerge.

Method

Sample

The sample consisted of 200 male offenders who were convicted for more than five offences each. Their mean age was M = 32.49 years (range = 15-64 years). More than 90% of the sample (92.5%) were older than 20 years. In terms of criminal career length, the mean was M = 15.66 years (range = 9 months-44 years); therefore, the sample consisted of highly criminal individuals who had rather extensive criminal careers. The most common offences the offenders in the present sample committed were burglary and theft non-dwelling (79.5%), theft (69%), shoplifting (75.5%), and handling (64.5%). The least frequent offences included sexual offences (indecent sexual assault, 2%; indecent exposure, 2%), assault with intent to rob (2%), manslaughter (1%), and threats to kill (1%). Table 1 presents the full list of offences with frequencies.

Table 1.

Offences With Frequencies and SSA Offence Labels.

Offence labels	Offences	%
1. BURG/THEFT	Burglary and theft dwelling	79.5
2. SHOPLIFT	Shoplifting	75.5
3. BURG/THEFT	Burglary and theft non-dwelling	70
4. THEFT	Theft	69
5. HANDLE	Handling	64.5
6. DESTROY PROP <2,000	Destroy/damage property less than £2,000	58
7. THEFT FROM VEHIC	Theft from vehicle	55
8. STOLEN GD	Handling stolen goods (receiving)	55
9. RESIST PO	Resist or obstruct police officer	47
10. BURG W/I	Burglary with intention to steal dwelling	45.5
11. ABUSE WORDS FEAR VIOLENCE	Using threatening, abusive, insulting words, or behaviour with intention to cause fear or provocation of violence	44
12. BURG W/I	Burglary with intention to steal non-dwelling	43.5
13. TWOC	TWOC	38
14. ABH	ABH	38
15. CRIM DAM	Criminal damage	36
16. POSS DRG B	Possessing drug class B	35
17. BATTERY	Battery	34
18. ASSAULT	Common assault	30.5
19. WEAPON	Possessing offensive weapon in public place	30.5
20. DECEPTION	Deception	29.5
21. THEFT PERSON	Theft from person	29
22. INTERF VEHIC	Interfering with a vehicle	27.5
23. TAKE CONVEY	Taking conveyance without authority	27
24. ROBBERY	Robbery	27
25. ASSAULT PO	Assault of constable	24.5
26. THEFT DWELL	Theft from dwelling	23.5
27. POSS DRG A	Possessing a drug class A	23.5
28. AFFRAY	Affray	23.5
29. ABUSE WORDS DISTRESS	Use disorderly behaviour or threatening/abusive insulting words likely to cause harassment alarm or distress	23
30. EQUIP THEFT	Going equipped for theft, other than theft of motor vehicle	22.5
31. BLADE	Having an article with blade or which was sharply pointed in a public place	20
32. BEING DRUNK	Being drunk and disorderly	17.5
33. POSS DRG C	Possessing drug class C	17
34. AGG VEHIC TAKE	Aggravated vehicle taking	16.5
35. THEFT CYCLE	Theft of cycle	15.5
36. WOUND	Wounding	15.5
37. DESTROY PROP	Destroy/damage property	15
38. THEFT OF VEHIC	Theft of vehicle	14.5
39. BURGLARY	Burglary	13
40. SUPPLY DRG A	Supplying class A drug	12
41. ESCAPE	Escaping custody/prison	11
42. RACIAL ASSAULT	Racial assault	10
43. PSS CNTL DRG	Possessing controlled drug	10
44. ENCLOSED PREM	Found on enclosed premises for unlawful purposes	9
45. FORGERY	Forgery	8
46. MAKE OFF	Making off without paying	8
47. PERVERT JUSTICE	Perverting the course of justice	7.5
48. PUB DISORD	Public disorder	7.5
49. EQUIP BURG	Going equipped for burglary	7
50. ARSON	Arson	7
51. GBH	GBH	6.5
52. HARASS	Harassment	4.5
53. FIREARM	Possess imitation firearms with intent to cause fear of violence	3
54. ASSAULT W/I ROB	Assault with intent to rob	2
55. INDECENT SEX	Indecent/sexual assault	2
56. INDECENT EXP	Indecent exposure	2
57. MANSLAUGH	Manslaughter	1
58. THREAT KILL	Threats to kill	1

Note. SSA = Smallest Space Analysis; TWOC = taking a motor vehicle without consent; ABH = actual bodily harm; GBH = grievous bodily harm.

Procedure

Data were derived from the criminal records of 200 offenders from a police database in the North West of England. The criminal records were not subjected to any stringent selection criteria. The only criterion was that there were over five offences within a criminal record to ensure rich and fruitful data were used to assess true patterns of criminal behaviours. Apart from this criterion, the records were selected randomly to get a wide and representative sample. Although official records are considered to account for only a small proportion of crimes committed, they assure valid information regarding criminal histories in that offences are classified according to the Home Office classification system. Guerette et al., (2005) suggested that previous research which aimed to assess the implications of specialisation is limited in that there are inconsistencies in crime category classifications. In addition to offence information, criminal records include court appearances and sentencing for each offence allowing any gaps due to incarceration to be evident (Blumstein & Cohen, 1987). As police information is not collected for the purpose of scientific research, it can be used as a valuable resource for research as it is an “unobtrusive or non-reactive measurement” (see, for a review, Canter & Alison, 2003) and therefore non-subjective to any researcher bias (Yokota & Canter, 2004). In addition, most of the offenders in the current sample had offending careers that included hundreds of arrests, convictions, and various punishments. For many of them, their careers spanned decades and for some the crimes happened when under the influence of alcohol and other substances; therefore, self-reported data may have been influenced by their ability to accurately recall all their offences. For these reasons, the validity and internal consistency of self-reports from the persistent and prolific offenders may have been the least reliable (DeLisi, 2001).

Another consideration during this phase was the offence categories included in the study and the decision to include all the different offences committed by the individual as it was available in the offender’s criminal record. As previous research has shown that using broad offence categories favours specialisation over versatility (Armstrong, 2008a, 2008b; Blumstein et al., 1988; Piquero, Paternoster, Mazerolle, Brame, & Dean, 1999; Sullivan et al., 2006), because each broad category consists of a large number of offence types, compared with a specific category, the authors decided not to collapse the crime types not wanting to miss important information and bias specialisation. Although collapsing crime types is a convenient way of coding data, this method can oversimplify and underestimate the extent and range of an offender’s criminal behaviour. For example, in many studies, the possession of a small amount of marijuana for personal use and the possession with intent to distribute cocaine are coded as a drug offence but these are significantly distinct crime types. Having few categories can impede the true understanding of offending patterns (Adams & Pizarro, 2014). Moreover, although problems by using legal definitions to classify crimes are well documented (T. Brennan, 1987) creating appropriate distinctions among different criminal acts is difficult and arbitrary. Legal classifications offer a comprehensive breakdown into many small categories of crime organised based on chapters of the penal code allowing an empirical identification of how they can be organised into themes that emerge form an individual’s criminal behaviour (Tumminello et al., 2013). The use of different offence categories across different studies only adds complexity when comparing results across studies (Nieuwbeerta et al., 2011). Keeping the Home Office classification system removes such complexities and adds to the potential value of the study for police investigations.

Analysis

Fifty-eight offences were identified in the criminal records and a data matrix was prepared in which the presence (1) or absence (0) of each of the 58 offences listed in Table 1 was noted for all 200 cases. The power of this form of recording police data has been proved in Canter and Heritage’s (1990) study. The data were analysed using Smallest Space Analysis–I (SSA-I; Lingoes, 1973). SSA allows a test of hypotheses concerning the co-occurrence of every variable with every other variable. In essence, the null hypothesis is that the variables have no clear interpretable relationship to each other. SSA is a non-metric multidimensional scaling procedure based on the assumption that the underlying structure, or system of behaviour, will most readily be appreciated if the relationship between every variable and every other variable is examined.

SSA represents the co-occurrence of variables, in our present study offences, as distances in a geometrical space. The SSA program computes association coefficients between all variables. It is these coefficients that are used to form a spatial representation of items with points representing variables. The closer any two points are to each other on the spatial configuration, the higher their associations with each other. Similarly, the farther away from each other any two points are, the lower their association with each other.

A number of studies of criminal actions have found such Multidimensional Scaling (MDS) models to be productive (e.g., Canter & Fritzon, 1998; Canter & Heritage, 1990; Canter & Ioannou, 2004b; Salfati, 2000). The particular power of SSA-I comes from its representation of the rank order of co-occurrence as rank orders of the distances in the geometric space (the use of ranks leads to it being considered non-metric MDS).

To test hypotheses, an SSA configuration is visually examined to determine the patterns of relationships between variables and identify thematic structures. Offences with similar underlying themes are hypothesised to be more likely to co-occur than those that imply different themes. These similarly themed offences are therefore hypothesised to be found in contiguous locations, that is, the same region of the plot. The hypothesis can therefore be tested by visually examining the SSA configuration.

The coefficient of alienation (Borg & Lingoes, 1987) indicates how well the spatial representation fits the co-occurrences represented in the matrix. The smaller the coefficient of alienation is, the better the fit, that is, the fit of the plot to the original matrix but anything up to 0.25 is considered good (Baddoo & Hall, 2002; Shye, Elizur, & Hoffman, 1994). However, as Borg and Lingoes (1987) emphasised, there is no simple answer to the question of how “good” or “bad” the fit is. This will depend on a combination of the number of variables, the amount of error in the data and the logical strength of the interpretation framework (Canter & Ioannou, 2004b; Salfati & Haratsis, 2001). Indeed, as the current study utilises data from police criminal records, which are not created for research purposes a relatively high coefficient of alienation would be acceptable as in many previous crime and other studies (e.g., Canter, Alison, Alison, & Wentink, 2004; Canter & Heritage, 1990; Doran, 2009; Doring, 2005; Yokota & Canter, 2004).

In summary, the SSA was used to explore the co-occurrences of the offences and allowed for the testing of the hypothesis that the offences will be differentiated into themes. Importantly, this analysis allows the questions regarding the existence of specialisation and the form that specialism may take to be addressed. Therefore, the SSA technique is used to identify this overall structure of offending behaviour, which is free from the restrictive assumptions that have concerned much of the specialisation literature in the past.

Results

Figure 1 shows the distribution of the 58 offences on the three-dimensional SSA. The coefficient of alienation of 0.269 indicates a reasonable fit for this type of data (Canter & Heritage, 2009). The regional hypothesis states that items that have a common theme will be found in the same region of the SSA space. As can be seen in Figure 1, visual examination of the SSA plot confirmed that it can partitioned into two distinct regions or themes, according to the offending styles of instrumentality and expressiveness. The strong division along this dominant axis does lend support to the distinctness of these offending styles. The configuration of the SSA plot suggests that offenders do specialise in certain types of crime and that these are incentive specific. The full variable descriptions are given in Table 1.

Figure 1.

Three-dimensional SSA plot of Expressive and Instrumental Offending Styles (coefficient of alienation = 0.269).

The Expressive Offending Style

Behaviours reflecting the Expressive offending style are located in the bottom right section of the plot. The expressive crime can be seen as one in which the act of committing the offence itself is the primary aim; therefore, here the behaviours can be seen as rewards of their own. According to Youngs (2004), these behaviours may be understood as a direct expression of some goal or need, in other words, the offence has some significance to the offender; that is, they get something out of committing the crime.

Examining closer this region, one will notice that offences involving violence form a distinct cluster. This is rather interesting because Feshbach (1964) originally observed that Expressive aggression is related to anger-inducing conditions whereby the goal is to make the victim of the offence suffer. While this was a theory of aggressive behaviours, it seems that this assumption still holds when broadened to encompass all crimes. This is especially evident in the violent offences that involve controlling the victim and causing harm such as Assault, Assault police officer, ABH, Manslaughter, Wounding and Racial Assault. The action of committing the violent offence and obtaining a sense of control over the victim is what motivates this type of offence. Interestingly, it seems that the threat of violence is also driven by a desire to harm, therefore perhaps the experience of controlling the victim is a reward in itself. For instance, behaviours such as “possessing an offensive weapon in a public place” and “having an article with Blade” serve as a way of maintaining force with fear, so that although these crimes do not involve a direct means of violent behaviour, they could be regarded as causing distress to a victim through fear of violence.

In addition, the carrying of a weapon suggests that the offender anticipates confrontation or even desires a violent altercation. What is more, the fact that the offender brings their own weapon implies that they have previous experience of violent confrontations and emphasises a preparedness to resort to violent crime. This further emphasises the notion that for these offenders, the goal is the violent encounter, they are prepared for it and embrace it, a point which is highlighted by the very close proximity of the variables BLADE and WOUND, this suggests that there is a strong chance that these behaviours will co-occur and that there is the intent to cause physical harm as well as fear in carrying weapons.

Of note within this small cluster of violent behaviours is the offence “Assault with intent to rob,” suggesting that although this crime may carry some monetary/instrumental value, the act of forcefully taking the property from the victim characterises and redefines it as an aggressive crime through which the control and suffering of the victim may be the main goal. The degree of force and dominance over the victim here determines the Expressive offending style. Indeed, within the literature, this crime is typically considered as an offence against the person rather than property.

While not all crimes within this region are overtly violent, they carry an element of aggression (Criminal Damage, Destroy/Damage Property) and psychological intimidation/suffering of the victim (the use of Abusive Words to cause fear of violence and distress). Although these behaviours do not involve a direct encounter with a victim, they are a form of indirect aggression toward an individual. These behaviours are more concerned with causing psychological harm or distress to a victim, and while they are still aggressive, they take on another meaning; the destruction is malicious in that the goal, as with the more violent offences, is to make the victim suffer.

While public disorder, drink, and drug offences are not direct expressions of some goal or need their presence in this region and their strong association with the violent offences/behaviours may mean that they influence the violent and anti-social behaviours that characterise this region, as it has been previously found that violent behaviour often results from drug and alcohol effects (Adams & Pizarro, 2014), and that many offenders when taken into custody for violent crime were under the influence when committing the offence (M. Felson, 2006; Parker & Auerhahn, 1998).

Toward the top of the region, the offence/behaviour of Destroy/Damage Property less than £2,000 is interesting because of its distance from the other criminal damage type offences, implying that this offence is not so concerned with the malicious intent to cause distress but associated with the thrill of actually participating in the offence that comes from breaking the rules, so this relates with the Expressive offending style in that the offence is a direct expression of some need for excitement. This is in line with research by Katz (1988) who suggested that Vandalism is a property crime without satisfying a desire for acquisition, arguing that it is an exciting attraction for the offender, where the act of the offence gives them a rush and a thrilling experience. The variable Shoplifting can be regarded in the same way as it offers an exciting attraction that is not explained by mere material necessity (Albelson, 1989). Accordingly, Katz proposes that Vandalism and shoplifting share a common thread where both are distinguished by the “sneaky thrill” that excites their practitioners. In the same way in the offence of Indecent Exposure, the ulterior aim is not sexual, rather the thrill of exposing themselves to the victim. The thrill and insult caused are the intended goal.

The Instrumental Offending Style

The behaviours in the top left of the plot reflect a more Instrumental Offending style. In direct contrast to the Expressive offending style, the instrumental act is primarily about something other than the offence itself. The offences are carried out not for their own rewards, but to achieve an ulterior aim, a secondary goal.

One of the most striking features in the plot is the way in which all the behaviours involving material possession of goods (i.e., Burglary, Theft, Forgery, Handling Stolen Goods, Theft of Vehicle/Cycle, Deception) cluster together in the space. Personal gain appears to play more of a central role within this region as most offences are property type offences that facilitate an ulterior goal. Typically, this is either through the possession of stolen goods, with the intention to sell or keep or a more direct form of monetary gain such as with forgery.

The offences appear to be more organised and almost impersonal in that offenders commit the crime only to achieve a secondary gain; the offence is committed solely to obtain something of value and benefit to the offender. The sense of planning involved here is emphasised by the presence of the variable Firearm within these offences. This is thematically distinct from the expressive behaviour of carrying a weapon, as it is used to facilitate the crime ensuring its successful commission. One can also argue that the presence of weapons is to provide security to the offender lending support to Feshbach’s (1964) claim that during instrumental offences, there is usually no premeditated intent to harm anyone, although he does point out that if someone interferes with the thief’s objective, the offender may be forced to become violent or else risk losing their goal.

In addition, this is also in accordance with the suggestion that instrumental offenders are less likely to harm, since strong violence toward the victim is not usually associated with the use of firearms (Lobato, 2000). It appears that taking a Firearm to the offence is not intended for violence but to act as a catalyst for encouraging the commission of the crime. The variable Threats to kill can also be interpreted in this manner, as it is also highly associated with the theft of goods. What appear to be violent behaviours are used to facilitate the crimes, and not to cause intentional suffering to the victim. This implies an unemotional and almost business-like transaction for the offender, supporting previous finding that the instrumental offender tends to treat the victim as an object or hindrance to their ulterior motive (Salfati, 2000).

The notion of gain and desired goods extends beyond their monetary value as it can be observed from the presence of Sexual Assault in this region as the victim is used as an object to obtain sexual gratification pertaining to an instrumental interpretation. When interpreted in the context of the adjacent variables, it emerges that it is consistent with the theme of “stealing” from the victim. Sexual assault is an invasive crime where sexual gratification is one more thing that can be stolen from the victim (Canter, 1994). One can observe that the variable sexual assault forms a cluster with the instrumental violent offences of Theft From Person, Robbery, and Affray. These offences differ thematically from the expressive violent crimes; they are not about the victim but obtaining gain for the offender. Moreover, it has been previously noted that Sexual Offenders rarely follow the “natural” career some might assume, such as previous convictions for voyeurism and indecent exposure, rather many convicted rapists do quite often have convictions for theft and violence (Canter, 1994; Lussier & Cale, 2013; Soothill, Francis, Ackerley, & Fligelstone, 2002).

In this Instrumental region, one can also notice the presence of the variable Arson. Here, the instrumental gain could arise from that Sexual Offenders rarely follow the “natural” career some might assume suggesting a form of criminal sophistication where arson is used to achieve goals. The proximity to harassment and the more violent instrumental offences is noteworthy, as it has been suggested that fires often involved prior threats and violence toward the victim (Canter & Fritzon, 1999).

An important observation is that all the “violent” offences within the instrumental region are close to the boarder, indicating that while violence is not the main motive of the crimes, it is a serious component within them, suggesting that offences such as Affray and Robbery could become much more violent and more expressive in their nature. This also holds for Grievous Bodily Harm (GBH), which is normally characterised by the harm caused during an ulterior goal, normally where lesser harm was intended but serious harm still resulted (English & English, 2003). The line between Instrumental violent offences and Expressive violent offences seems to be very fine. Perhaps this is concerned with the role the victim plays for an offender during the offence?

Discussion

The present study reveals that criminal history patterns can be differentiated in terms of Expressive or Instrumental offending styles. As Youngs (2001) noted, the Differentiation (along with the Repetition and Exclusivity of behaviour) is required to support the specialisation hypothesis. The focus of the present study is the Differentiation component.

This model of criminal differentiation is based on the thematic interpretation of the criminal careers of offenders, which suggests that offenders can be discriminated in terms of the motivation and the goals an offender wishes to achieve. This model broadens Feshbach’s (1964) work on Expressive and Instrumental aggression to all crimes in general and supports previous research that has found it to be appropriate for differentiating offenders, distinguishing the type of crimes offenders commit and also as a way of understanding criminal careers (Lobato, 2000; Miethe & Drass, 1999; Salfati, 2000; Salfati & Canter, 1999; Salfati & Haratsis, 2001; Santtila et al., 2003; Trojan & Salfati, 2010). This differentiation of what the offender does complements Investigative Psychology studies (Canter & Youngs, 2009) that focus on how the offence is committed.

The crimes within the Expressive theme are characterised by the desire to harm and control the victim gaining gratification from the suffering of others. This theme reflects offenders who deal with people and situations as having direct emotional impact upon them, thus the crimes here can be seen as a direct emotional interaction with the victim. It is this interaction with the victim that distinguishes between Expressive and Instrumental specialisation.

For the expressive offender, the victim is significant and this is supported by previous research that has found interpersonal interaction with the victim to be a key component in Expressive crimes where the target of the offence is the victim and the goal is the enjoyment from controlling them. The interpersonal transaction between the offender and the victim is an act of emotional expression (Katz, 1988), where the offender is interacting directly with the victim and the offence is about the impact that they have on them. Salfati (2000) found that the expressive theme of homicide was composed of behaviours that centred around the victim as a specific person. She also proposed that it is important for offenders within this theme that the victim represents a specific person; in other words, they are not just a body but an embodiment of a person significant to the offender. Expressive types of offending behaviour are often found to occur between individuals known to one another (Santtila et al., 2003; Trojan & Salfati, 2010) supporting the notion that the victim is important for these types of offenders (Salfati, 2003).

Impulsiveness, an emotional reaction reckless in its nature, is another important feature in this theme that has previously been associated with Expressive offences (Salfati & Canter, 1999; Trojan & Salfati, 2010). Feshbach (1964) suggested that the expressive type of aggression occurs in response to anger-inducing conditions, resulting in an immediate interpersonal confrontation that is most likely to occur against someone the victim knows intimately (Salfati, 2003).

Expressive crimes are impulsive and emotional as opposed to planned like one can see with the most instrumental crimes. The Instrumental theme relates to the search for rewards that the crime provides the offender, such as monetary gains. This offender has a more sophisticated criminal past highlighted by the presence of the variable ESCAPE that reveals previous imprisonment and a criminal lifestyle.

In terms of the transaction between the offender and the victim, instrumental crimes indicate an impersonal approach. In contrast with expressive crimes, here the offender views the victim not as a person, but rather as an object through which they can obtain their desired goal. The interaction with the victim is purely to meet the needs of the offender, in some ways, the victim is inconsequential and only necessary to satisfy either the sexual or material needs of the offender and any violence that ensues will be a by-product of the main objective. Canter and Youngs (2009) have previously drawn attention to the importance of the victim role within an offence. They argue that “the victim as Object offences are those crimes in which the offender sees the victim as having very little, if any, human significance or emotions and towards whom he has no feelings” (p. 292). As Canter and Youngs note, the victim is not credited with an active part in the situation but is there only for the offender to act upon, and thus an object. The exploitative nature of the instrumental offender has been found in previous research (Canter, 1994; Salfati, 2000; Trojan & Salfati, 2010) where both people and property alike are treated as a means to satisfy the offender’s needs.

The interpersonal interaction with the victim has previously been found to be a key component in Expressive and Instrumental crimes (Canter & Youngs, 2009; Salfati, 2003), where the victim is either the target of the offence and the goal is the enjoyment from controlling them or is there only for the offender to act upon and inconsequential to the offence as a whole. Marshall and Kennedy (2003) supported this notion arguing that Instrumental and Expressive types of offending behaviour can be distinguished in terms of degrees along a continuum from sufficient force, through gratuitous violence to silence a victim and expressive violence to sadistic violence. They further posit that the victim role will map on to this continuum, as it moves away from the highly expressive victim as Person, where the specific quality of the interaction with the victim is key to the offence, to the least expressive role where the impact on and the reactions of the victim are insignificant, and therefore treated as an object (Canter & Youngs, 2009).

The current findings are important in understanding how offenders may specialise in their offending behaviour. Expressive and Instrumental offending styles not only represent specialism within criminal careers but may also indeed be a reflection of the core dimensions of all offending behaviour. This is consistent with previous research that has indicated a distinction between Person and Property specialisation (P. Brennan et al., 1989). Although Expressive and Instrumental offending styles are not necessarily divided along these lines, there is an implicit suggestion that this may be at the crux of differentiating between offenders as it was found when looking at the interpersonal transaction between the offender and the victim. While previous works have posited that offence specialisation and versatility may be a product of low self-control or variations within offenders or a learned behaviour, it appears that other dynamics might be relevant in the commission of specific types of crimes. With regard to specialisation, it seems that what goals the offender wishes to achieve drives his offending behaviour that operates on two levels; the interpersonal interaction with the victim and the nature of goal that is motivating the crime.

The implications of instrumentality and expressiveness being distinct offending styles can potentially help policy makers identify appropriate prevention and intervention initiatives. For policy makers, the extent to which offending patterns are diverse or specialised reflects on the feasibility of preventing certain types of crimes. The identification of expressive and instrumental offending styles can have implications for the development of rehabilitation programmes that target specific forms of crimes and “types” of offenders depending on what goals the offender wishes to achieve. In addition, the findings can prove very useful for police investigations, as they suggest that offenders are fairly consistent in their criminal activity participating in offences that are carried out for a secondary goal, or committing crimes that are a direct expression of a goal or need. The finding of specialisation implies that knowledge about earlier crimes within a criminal career will help officials predict later offences (Soothill et al., 2009). For example, if the police are dealing with a sexual assault, rather than inferring that the offender will have a criminal history of other sexual offences they may need to focus on offenders with a more instrumental criminal career. The identification of distinct offending styles will enable the investigating officers to prioritize suspect selection and lead to a quicker identification of the offender (Salfati & Canter, 1999). In addition, the knowledge of the patterns of criminal careers can be utilised to assist in the identification of suspects; by understanding the course of the criminal career may enable investigators to identify suspects (Snook, Wright, House, & Alison, 2006). The finding that offenders tend to specialise in Expressive and Instrumental offending could offer a foundation for developing prioritization techniques.

While the identification of distinct themes of offending behaviour is particularly useful in suggesting the existence of specialisation for the above model to be stronger as providing conclusive evidence of specialisation and more than only suggestive, Youngs (2001) proposed that one need to take into account individual variations; which offenders are specialists and which are not, how offenders may change over time by considering their career lengths and age of onset (Tzoumakis, Lussier, Le Blanc, & Davies, 2013). These issues are addressed in separate analyses.

One limitation of the current study was the relatively small sample size and that it was geographically limited. Further studies with a larger sample need to investigate expressive and instrumental offending within the specialisation versus versatility debate.

Further research should also look to combine the use of criminal records with information from self-reports producing richer data not only about the criminal histories of offenders but also about the “type” of offender who is likely to specialise in expressive and instrumental offending styles. This would provide much more information regarding the motivation to offend for these offenders and lead to better intervention and treatment methods. The current study used only official records and while research into criminal careers research requires exact information about the timing of offences and the progression of offences (Farrington, 1992) as is provided via official records, these represent only the “tip of the iceberg” of criminal activity as many criminal acts go undiscovered (Brame, Fagan, Piquero, Schubert, & Steinberg, 2004). Although many studies have reported a high degree of concordance between self-reports and official records (e.g., Moffitt, Caspi, Dickson, Silva, & Stanton, 1996), official data underrepresent the degree of total offending and may overrepresent more serious crimes that are cleared at higher rates. Moreover, results show that the conclusions drawn from studying specialisation may vary depending on whether self-report or official records are used (Lynam et al., 2004). Therefore, reliance on official records as a measure of offending patterns potentially limits the generalisation of the current findings to the broader population of offenders not detected by the system. Self-reported data may have produced different findings.

Conclusion

The main question of the current research was whether offenders tend to specialise in their offending careers and the form that this specialisation takes. The identification of two distinct themes suggested that offenders tend to specialise and that this specialism takes the form of either Instrumental or Expressive offending behaviours. These specialisms are related to the motivation behind the offence; whether the offence is carried out to achieve some secondary personal gain or whether they can be understood as direct expressions of a particular need that in turn determines the interpersonal transaction between the offender and the victim. For this model, though to become anything more than suggestive, further research is needed in terms of individual variations and offenders’ development over time. Perhaps only then we will reconcile the paradox of specialisation and versatility.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

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