Definitions of harmful sexual behaviour

Defining harmful sexual behaviour (HSB) in young people is problematic because of changes across time and culture regarding what is considered 'normal' sexual behaviour, as well as how a 'child' is defined (Fowler 2016; McNeish 2018; Veneziano 2002), and because many do not come to the attention of authorities for investigation, prosecution or treatment (Shlonsky 2017). The ratio of self‐reported to adjudicated sexual offences by young people is estimated to be between 12:1 (Lee 2012) and 25:1 (Elliott 1995) respectively. This may be due to non‐disclosure by victims, unwillingness on the part of victims to prosecute or an inability to provide sufficient evidence. Victims of sexual offences may not disclose for many reasons, including fear, not knowing who to tell, believing what is happening is normal, or communication problems, particularly for children with learning disabilities. In the UK, a prevalence study showed that 83% of young people aged 11 to 17 years old who had been sexually assaulted by a peer had not told anyone about the assault. This is considerably higher than the 34% non‐disclosure rate of those sexually assaulted by an adult (Radford 2011). Under‐reporting may also be, in part, due to a reluctance by communities, particularly in certain cultures, to discuss sexual issues, deviant or otherwise (Grant 2000). Some harmful behaviour may be excused as 'exploratory' in nature and something that the young person will 'grow out of' (Barbaree 2006).

Sexual offences committed by youths encompass a wide spectrum of behaviours, in a variety of situations, with many types of victims (Hackett 2019; Kemper 2010; Righthand 2004; Ryan 1997; Scottish Government 2020). What is defined as a sexual offence differs across jurisdictions, as does the age of minimum criminal responsibility. In most jurisdictions, young people aged 12 years or older are considered by law to be old enough to be held criminally responsible, but not sufficiently old to be subject to the full range of adult criminal sanctions (Barbaree 2006; Hoghughi 1997). Civil measures of welfare, care, assistance, diversion programmes and protection may be triggered when children younger than the age of criminal responsibility are suspected of illegal acts. On attaining the age of criminal responsibility, the possibility exists of adult penal procedures and sanctions, although these are not always used and 'age threshold offenders' may not come to the attention of the criminal justice system (Cipriani 2009; Department of Health and Home Office 2006). Table 1 contains details of the minimum age of responsibility for criminal activities in various countries (Cipriani 2009). For the purposes of this review, a young person with HSB is defined as a person aged between 10 and 18 years old who has been reprimanded, warned or convicted of a sexual offence, or who has received civil measures for their sexual offending.

Prevalence

There are few studies upon which to base population estimates of the prevalence of HSB and they all vary considerably in their estimates (NSPCC 2019; Warner 2015). In the UK, estimates of official cases over a year suggest that about one in 1000 young people aged 12 to 17 years old is identified as displaying HSB (Department of Health and Home Office 2006). Around a third of child sexual abuse is by other children or young people, with estimates ranging from one fifth to two thirds (Hackett 2014; NSPCC 2019; Radford 2011). Young people comprise a large proportion of those reprimanded, warned or convicted of sexual offences. In England and Wales, the number of police recorded sexual offences against under‐18 year olds, by under 18‐year olds, rose from 5215 in 2013 to 9290 in 2016 (NSPCC 2019). Children and young people aged 10 to 19 years old were the alleged offenders in 26% of sexual offences committed in Australia between 2015 and 2016 (Australian Bureau of Statistics 2017). In Germany, data from the Police Criminal Statistics Bureau indicates that juveniles aged between 14 and 20 years old are over‐represented in the category of 'sexual offences' (equivalent to one young person convicted of HSB per 1000 young people aged 14 to 20 years old in the general population) (Bullens 2004). Many young people displaying HSB have more than one victim: a study in The Netherlands found that the victim(s) were known to the offender in two thirds of the cases; half of the youths had victimised one person, 15% had two victims and 35% had victimised more than two people (Bruinsma 1996). To date, there has been little research into technology‐assisted HSB, although it is a potentially growing population (Hollis 2017; Lewis 2018). There is some cross‐over between online and offline HSB and between child sexual exploitation and HSB (Belton 2016; NSPCC 2019).

Profile

Young people engaging in HSB are not a homogeneous group. They show great variation in terms of their backgrounds, presenting problems and types of HSB, including those categorised as offences (Balfe 2020; Letourneau 2014; Malvaso 2020; Murphy 2017; Rich 2009; Veneziano 2002). Assessment tools may screen for whether behaviour is developmentally normal or HSB, or assess HSB behaviours and risk of recidivism. The evidence around these tools is very limited (Campbell 2016b; Schwartz‐Mette 2019; Worling 2017).

Risk factors for adolescent sexual offences are very similar to those observed for other forms of serious antisocial behaviour (Letourneau 2009; Van Wijk 2005). There are currently no validated classifications of young people with HSB. Some attempts to define subtypes have been offence‐driven (for example, rapists, child molesters), whereas others have been based on personality (for example, disturbed impulsive, pseudo‐socialised) (Veneziano 2002). Others have suggested categorisation by victim age (offending against children versus adolescents or adults), co‐offender status (offending as individuals or in groups) and crime history (with or without a previous history of crime) (Aebi 2012). Some have been described as having poor interpersonal skills, being socially isolated, lacking empathy and evidencing distinctive patterns of making claims on others (Epps Fisher 2004; Lane 1997). There may be evidence of psychiatric disorder (for example, conduct disorder, attention deficit disorder and adjustment disorder), low self‐esteem, depressive or anxious symptoms, antisocial behaviour (especially amongst juvenile rapists) and neuropsychological impairment (for example, impulse control problems, poor planning, lifestyle impulsivity and deficits in verbal cognitive functioning) (Sheerin 2004).

Some have a history of maltreatment or victimisation (physical, sexual or emotional abuse, neglect, witness to family violence) (Barra 2018; Bruinsma 1996). Being sexually abused as a child has been strongly linked to young people displaying HSB (Shlonsky 2017). They may exhibit cognitive distortions relating to the negative effects of the offence, blaming the victim and sexual attitudes or knowledge. Deviant sexual arousal may be reported (Seto 2010). Although not all families are dysfunctional, some are characterised by poor relationships, negative communication styles, instability, disorganisation and violence. The young person may have experienced a lack of adequate support and supervision, parent‐child attachment problems and physical or emotional separation from one or both parents (Bartosz 2016). Their parents may also have experienced mental health problems (Duane Morrison 2004; Långström 1999). Whilst some young people experience academic and behavioural problems in school, as well as learning difficulties, others show above average cognitive performance (Veneziano 2002).

Significant differences have been reported between younger perpetrators and older children. Pre‐adolescent children are likely to show less problematic or severe HSB, whilst the early teens are the peak time for HSB, most of which is displayed by boys (McNeish 2018). Studies show between 92% and 97% of young people showing HSB are male and 3% to 8% are female (NSPCC 2019).

Young people with learning disabilities are over‐represented in treatment services, although their offending behaviour is not thought to be linked to their learning disability per se (Department of Health and Home Office 2006). Whilst there are many similarities between developmentally‐disabled and non‐disabled youth in the range, types and elements of HSB, there are some differences in the associated cognitive process, the context of the behaviours and the level of sophistication (Lane 1997). One study found that these young people are more likely to suffer impulse control; less likely to be redirected by adults when displaying concerning behaviours; and less likely to receive sex education (Evertsz 2012). They are also at a greater risk of experiencing abuse and neglect, which can put them at an increased risk of trauma and sexualization (Evertsz 2012). Although there are few follow‐up studies, a recidivism rate of almost 31% has been reported for sexual offences among offenders with an intellectual disability, with the vast majority of re‐offences (84%) occurring in the first 12 months (O'Callaghan 2004). With respect to gender differences, young female perpetrators may be less likely than males to use violence, and there can be differences in perceptions, affective reactions and internal experience (Lane 1997). Juvenile females with HSB may be more likely than males to be slightly younger, more likely to be white and more likely to have a co‐offender. Females are less likely than males to commit rape and less likely to be processed formally by law enforcement (Vandiver 2010). Some studies suggest that females are also more likely to have been sexually victimised themselves (Bumby 2004). Young people who show violence as well as HSB manifest extreme offences, attitudes, dynamics and behaviours reflecting a disregard for other people's safety and welfare. They exhibit considerable psychopathy and their offences may include using weapons to injure their victims, sadism, ritual abuse or murder. They are unlikely to be treated in the community and overall the prognosis for change is thought to be poor (Lane 1997).

Most young people do not continue HSB into adulthood, although there is a subgroup at high risk for doing so (Cale 2016; Department of Health and Home Office 2006; Dopp 2017; Hackett 2013). Re‐arrest rates for registered juveniles with HSB in adulthood are as low as 5% (Vandiver 2006). Re‐offending rates for juveniles in England and Wales were 15.6% for sexual offences in 2016 (Ministry of Justice 2018). Predicting which adolescents are at greatest risk to sexually recidivate is very difficult. There is limited knowledge about which predictors are most accurately linked to sexual recidivism (Caldwell 2010), and uncertainty over how to best use instruments designed to predict re‐offending (Martinez 2007; Vitacco 2009), including use with particular groups such as individuals with intellectual disabilities (Griffin 2012) and non‐Western populations (Chu 2011). Young people with HSB are more likely to re‐offend with non‐sexual offences than sexual recidivism: observed recidivism rates for new sex offences tend to be quite low at around 10%. In a two‐year follow‐up study, young people convicted of a sexual offence were nearly 10 times more likely to have been charged with a non‐sexual offence than a sexual offence (Caldwell 2007). This highlights the need for interventions to focus on broad‐based behavioural and developmental goals and not just on preventing further sexual offending (Borduin 2009; Hackett 2004). Around half of all adults convicted of sexual offences report that their sexual deviance began during their childhood, and often their offences escalated in frequency and severity over time (Veneziano 2002; Zolondek 2001). It is important to identify those young people at risk of further offending and provide them with effective interventions and support. Services should avoid stigmatising young people as 'mini adult sex offenders' (McNeish 2018). Risk factors for both sexual and non‐sexual recidivism include unhealthy family environments, negative peer affiliations, social isolation and chronic or pervasive antisocial values and behaviours. Being highly impulsive, holding attitudes supportive of abusive behaviours and failing to complete treatment (or being terminated unsuccessfully from treatment) are also predictors. Risk factors specific to sexual recidivism include deviant sexual arousal, sexual compulsivity, sexual preoccupation, past sexual offences against two or more victims and the targeting of strangers as victims. These are similar to the risk factors of sexual recidivism amongst adults convicted of sexual offences (Worling 2003). An eight‐year follow‐up study of Canadian adolescents who had sexually offended found recidivism rates of 45% for a new criminal offence, 30% for a violent offence and 10% with a sexual offence. Paternal abandonment, childhood sexual victimisation, association with significantly younger children and having victimised a stranger were associated with a higher risk of sexual recidivism (Carpentier 2011).

Management of children and young people who present with HSB

Often the response to young people engaging in HSB is one that seeks to restrain or contain the young person by means of restrictions on their liberty, exclusions (from school, or social gatherings) or surveillance of some kind. Clinical treatments for juvenile HSB include behavioural conditioning, pharmacological responses, family systems interventions, rational‐emotive counselling, music and art therapy, 'cycle'‐based approaches, cognitive‐behavioural therapy (CBT), relapse prevention programmes and ecological multisystemic approaches (Borduin 2015; Dopp 2015). Treatment programmes are often tailored for individual needs and may combine several approaches, even when they are theoretically quite different (Allardyce 2018; Campbell 2016a; Chaffin 2002; NICE 2016). Few are manualised (Marsh 2019). Treatment may be delivered individually or in a peer‐group environment, although concern has been expressed that this can sometimes have negative effects through delinquent peer influences and socialisation into delinquent behaviour and belief patterns (Chaffin 2002). More programmes now involve the young person's family (Calvert 2019; Campbell 2020; Dopp 2017; Letourneau 2009; Thomas 2004).