By Dr Michael Davis MAPS, Centre for Forensic Behavioural Science, Monash University

Forensic psychologists are frequently requested to assess and treat individuals who have been charged or convicted of sexual offences against child victims. This can be a difficult task as child sexual abusers are a very heterogeneous population. Accordingly, an appropriate treatment or management pathway for one offender may be contra-indicated for another. One useful distinction is to determine whether the offending behaviour primarily reflects a deviant sexual interest in children or other motivations.

However, formal DSM-5 and ICD-10 criteria are not particularly useful for this task. Indeed, the DSM-5 criteria for ‘pedophilic disorder’ (APA, 2013) and the ICD-10 criteria for ‘paedophilia’ (WHO, 1992) seemingly depend upon the offender honestly describing their sexual fantasies at interview. But this cannot simply be assumed in forensic assessment. Accordingly, analysis of offence behaviours becomes a crucial source of data.

Typologies of child sexual abusers

While the two formal diagnostic manuals are not particularly helpful in differentiating child sexual abusers, the prepared clinician can draw upon a number of classification systems to assist in developing a detailed formulation. Useful clinically-derived child molester classification systems have been published since the 1960s (see Knight & Prentky, 1990; Prentky & Burgess, 2000). One of the major distinctions in the majority of these typologies has been between fixated or preferential paedophiles who have a genuine sexual interest in children and those who offend for other reasons (Dietz, 1983). This distinction has a strong empirical rationale. Meta-analyses of sexual re-offending have routinely noted that sexual deviance is the most potent risk factor for recidivism (Hanson & Morton-Bourgon, 2005; Mann et al., 2010). Moreover, classification as a fixated offender has been found to significantly discriminate between recidivists and non-recidivists in samples of child molesters (Prentky et al., 1997).

There are a number of typologies and classification systems described in the scholarly literature. Three in particular appear to be especially useful for clinical and applied purposes. These are the Massachusetts Treatment Center: Child Molester Typology (Version 3; MTC:CM3; Knight et al. 1989), the behavioural typology by Canter and colleagues (1998), and the motivational continuum by Lanning (1985, 2010). The latter two were initially developed for use in criminal investigations and thus focus on offence behaviour. There is considerable overlap between these three typologies. Accordingly, due to space constraints this article will focus on the latter, whilst also pointing out some of the overlap with the other two classification systems.

Lanning’s (1985, 2010) typology is a rationally-derived system that initially divided child sexual abusers into four ‘situational’ types and three ‘preferential’ types. However, this evolved over time and the current version of this system envisages child sexual abusers, as well as sexual offenders in general, on a motivational continuum from the situational to the preferential. This acknowledges the fact that behavioural patterns amongst such offenders are not mutually exclusive and there can be multiple motivations for committing such crimes. It is thus particularly useful in applied settings, as individuals can be considered at any point along the continuum.

Situational offences

Those offences towards the situational end of the continuum are thought to reflect basic sexual needs such as lust, or non-sexual needs such as power or anger. Such offenders usually do not have a genuine sexual interest in children, but may molest them for a number of often complex reasons. Their offending is often impulsive and opportunistic. Three major patterns of offence behaviour have been identified at the situational end of the continuum: regressed, morally indiscriminate and inadequate.

The regressed pattern of behaviour involves individuals who do not have a sexual preference for children, but who turn to them as a sexual substitute. This often occurs during times of stress and such offenders tend to have poor coping skills and low self-esteem. Children are chosen due to their availability. Accordingly, incest offenders can often, though certainly not always, be characterised in this fashion.

The morally indiscriminate pattern of behaviour involves the sexual abuse of children as simply another form of antisocial behaviour in the offender’s life. A diagnosis of antisocial personality disorder, and elevated levels of psychopathic personality features, are often found in these offenders. Victims are chosen due to vulnerability and opportunity. Force, lures or manipulation may be used and the victims may be abducted. Pubescent children are thought to be particular targets of such offenders. Canter and colleagues (1998) identified a comparable pattern of behaviour that they called the ‘criminal-opportunist’. These offences were characterised by stranger victims, outdoor offences, one-off offences, offender intoxication, offender ejaculation, and vaginal penetration.

Those who engage in the inadequate behaviour pattern include an array of withdrawn and 'unusual' individuals such as eccentric personalities, psychotic individuals, or those with an intellectual disability or senility. It is of course important to note that most people with these difficulties will not sexually abuse children. The inadequate offender does not have a sexual preference for children, but targets them because he finds them to be non-threatening. As such, these offenders may also target the elderly as well. Lanning (2010) reported that sexually-motivated child murders profiled by the FBI usually involved either the morally indiscriminate or inadequate patterns of behaviour.

Preferential offences

Those offences at the preferential end of the motivational continuum reflect deviant sexual needs, most obviously a sexual preference for children. Four major patterns of offence behaviour have been identified at the preferential end: seduction, introverted, sadistic and diverse.

As the name suggests, the seduction pattern of behaviour characterises individuals who essentially engage with children by seducing and grooming them with affection, attention and presents. These offenders are able to identify with their victims. They know how to talk and listen to children and often target those who are neglected. Over time they gradually lower the child victim’s sexual inhibitions until they are willing to engage in sexual behaviour because of the benefits that they are receiving. Such offenders may simultaneously abuse multiple victims. If threats or physical violence are used they are likely to be instrumental in nature and are made to avoid identification or disclosure. Such offenders can abuse the same child for lengthy periods of time and may even find it difficult to get the child to leave when they age and become too old for the offender. Canter and colleagues (1998) identified a comparable behavioural pattern that they termed ‘intimate’. This was characterised by the promise of gifts, reassurance of the victim, affection, desensitisation, kissing, and the offender performing oral sex on the victim.

The confronting nature of ‘seduction’ child sexual abusers
Descriptions of any form of child sexual abuse are by their very nature confronting. However, this is especially the case with the seduction pattern of behaviour. The suggestion that children may willingly ‘trade’ sex with their abusers for affection or gifts can be problematic for professionals whose representation of such offending is a child who actively resists being physically forced into unwanted sexual acts. Nonetheless, it is crucial that clinicians remember that “when an adult and child have sex… the adult is always the offender and the child is always the victim” (Lanning, 2010, p. 26). Without being cognisant of this, clinicians can significantly add to the subsequent shame, guilt and embarrassment that victims of these offences can experience later in their lives.


The introverted behavioural pattern characterises offenders who have a sexual preference for children but essentially lack the interpersonal skills required to successfully groom and seduce them. Such offenders are similar to the inadequate situational offender, but they do have deviant sexual preferences. As such, their selection of child victims is more circumscribed and predictable across multiple offences. The lack of interpersonal skills means that these offenders engage in minimal verbal communication with their victims, who are often strangers. Such offenders are more likely to attend playgrounds or other areas where children gather.

The sadistic behavioural pattern involves offences in which the child’s response to the infliction of suffering, humiliation, or pain is sexually arousing. Essentially, these offenders would meet formal diagnostic criteria for both paedophilia and sexual sadism. Thankfully such offenders are rare. Perhaps unsurprisingly, they are more likely than other preferential offenders to abduct and murder their victims.

The diverse behavioural pattern was previously termed ‘sexually indiscriminate’ and was initially thought to be a situational type as such offenders do not have a preferential sexual interest in children. Nonetheless, under the current motivational continuum such offences are situated toward the preferential end because their diverse offending reflects sexual deviance and they may meet criteria for several paraphilic disorders. Indeed, the facetious term ‘try-sexual’ is also used to describe such offenders because they are indiscriminate in their sexual interests and willing to try a wide variety of sexual behaviours. There is some similarity to the morally indiscriminate situational offending pattern, however the diverse offender has deviant sexual interests and is often more discriminating in their non-sexual behaviours.

Given the range of behavioural patterns at either end of the continuum, it is perhaps clear that further dimensions beyond the situational-preferential dimension are needed for a truly comprehensive typological system. To this end, a recently proposed elaboration of the MTC typology (MTC:CM4) involves three dimensions: fixation, social competence and externalising behaviour (Knight & King, 2012). This will undoubtedly be an interesting development.

Applications to clinical practice

Behavioural typologies reflect the heterogeneity of child sexual abusers and provide some useful indications for differentiating between preferential and situational offenders. The notion of a motivational continuum is particularly useful in clinical practice as the need to awkwardly force offenders into discrete categories is removed. Indeed, some offenders can be envisaged in the middle of this continuum with a preferential sexual interest in children as well as an awareness of situational opportunities to offend. This focus on offence behaviour can assist clinicians in understanding how child sexual abusers commit their offences. This knowledge can be very useful in preparing interview strategies, conducting risk assessments, and formulating treatment and management plans. Risk assessment can be aided by a more considered evaluation of sexual deviance and the likely nature, severity or imminence of any future offending. This can flow into appropriate recommendations for treatment and management, and thus provide the most appropriate interventions in the individual case.

The author would like to thank Dr Deb Bennett for her helpful comments.

The author can be contacted at


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Further reading

  • Douglas, J. E., Burgess, A. W., Burgess, A. G., & Ressler, R. K. (2013). Crime classification manual: A standard system for investigating and classifying violent crime (3rd ed.). Hoboken, NJ: Wiley.
  • Napier, M. R. (2010). Behavior, truth and deception: Applying profiling and analysis to the interview process. Boca Raton, FL: CRC Press.
  • Oliva, J. R. (2013). Sexually motivated crimes: Understanding the profile of the sex offender and applying theory to practice. Boca Raton, FL: CRC Press.

InPsych October 2013