Sex offenders with learning/intellectual disabilities: comparing the efficacy of psychological interventions in and out of secured hospitals.
There has been a paucity of literature that investigates the effectiveness of psychological treatment programs for sex offenders with learning disabilities. In the main, these studies focused on mainstream sex offenders (Murphy et al., 2010; Ralfs and Beail, 2011; Sakdalan and Collier, 2012); and the literature available in the public domain had an insufficient number of follow ups or samples (Goodman et al., 2008; Heaton and Murphy, 2013). Due to the lack of research that encompasses offenders with learning disabilities, the issue of developing effective programs that reduce recidivism is becoming ever pertinent. This paper’s mandate is to examine the literature available that investigates the effectiveness of sex offender treatment programs that are currently instituted and performed by clinicians. Recent developments in sex abusive behaviour (no doubt exacerbated by the intensive media interest surrounding it and sensitivity of the issue) have heightened the urgency to increase the follow-up years for those who have received treatment to avoid further offending and the chance of relapse.
The structure of the essay contains three main elements is divided into three parts, to allow comprehensive coverage of the subject matter. Firstly, the review shall focus on the causes of sex abusive behaviour among people with learning disabilities and attempt to differentiate and discern between inconsistencies in terms of sample sizes, data analysis and research settings, all of which are variables which can impact on the causation that causes people to sex offend. There is also a growing consensus about the diversity of studies that investigate the causes of sex abusive behaviour, and these mostly centre around things such as the association of arousal patterns and cognitive distortions. Secondly, sex offenders’ treatment programs shall be disseminated; variations and their relevance to learning disabilities clients will be a integral component of this section of the essay. Finally, the rate of re-offending specifically among offenders with learning disabilities is reviewed, appreciating the argument that some of the incidents that happen in the community are not reported to the appropriate authorities (Brown and Thompson, 1997).
Causes of sexual abusive behaviour
There is some anecdotal evidence linked to the causes of sexual abusive behaviour amongst people with learning disabilities. Most of the studies link abusive behaviour with sexual arousal patterns, cognitive distortions and inexperience of intimacy of sexual knowledge (Goodman, 2008; Murphy et al., 2010; Haunt and Brewster, 2010). However, as with most non-disabled counterparts the vast majority of these offences are not reported to the authorities (Murphy et al., 2010; Brown and Thompson, 1997; Day, 1994), which could potentially exacerbate the abuse that the afflicted suffers. Several authors have reported a history of sex offending as being prevalent among people with learning disabilities. For instance, Lindsay (2002) observed that 62 percent of referrals of sexual abusive behaviour had a history of sexual offending, a reliable statistic, although it is one which is further corroborated by a study which had a sample of ‘paedophiles and gynephilic offenders (n=991) that associated patterns of sex offending with a below average IQ where the intended victims were young children (Blanchard et al., 1999). The studies above suggest that there is not a consensus or criteria to report sexual abusive behaviour among people with learning disabilities.
In recent years there has been a growing association of sexual abuse in childhood with sexual abusive behaviour; particularly through media channels, although there is little evidence to substantiate this claim. Despite this statement, Langevin (1992), Beail (1995), Murphy et al. (2010), Heaton and Murphy (2013) have all identified that behavioural problems such as sex abuse might be linked to sex abuse in childhood. Similarly, a study comparing a sexually abusive history of 46 sexual against 48 non-sexual behaviours concluded that 38 percent of sexual participants experienced sexual abuse in their childhood and 33 percent of non-sexual participants had experienced physical abuse (Lindsay, 2002). However, such circumstantial findings do not account for the remaining 62 percent of the sex offenders who were not abused during their childhood, merely indicating a slight link between sex abuse in childhood and the risk of repeating this later on. It is important that other factors besides sexual abuse during childhood are considered when understanding the causation of sexual offending (Murphy et al., 2010) or else this might be linked to the recent diagnosis of psychosis as inhibiting people with learning disabilities (Lindsay, 2004).
Psychosis is a diagnosis mostly linked with general causes of abusive behaviour among sex offenders with learning disabilities. Empirical studies reported that just under a third of sex offenders with learning disabilities were also diagnosed with psychosis (Haunt and Brewster, 2010; Lindsay et al., 2002). Correspondingly, Murphy et al. (2010, pp. 538) also found that ‘mental illness, anxiety and alcohol abuse’ are prevalent among people with learning disabilities and sex offenders, perhaps understandably so. One problem is that the study by Quensey et al. (2004) identified a lower percentage of repeat offenders with schizophrenia compared to those who had not reoffended with schizophrenia. In another study, Lindsay et al. (2004) identified that 52 percent of sex offenders were diagnosed without mental illness; instead there were issues about inconsistencies in mood disorders and lack of interpersonal skills. Interestingly, the studies above are not strong when considering psychosis as a cause of sex abusive behaviour among people with learning disabilities. Adding to this, most of these studies did not differentiate or distinguish behavioural disorders from mental illness as disinhibitions of sex offending; ultimately, there were variations in terms of sample sizes, IQ determinations and diagnosis.
In the past decade, innumerable studies have attempted to identify the cause of abusive behaviour among sex offenders with learning disabilities. Goodman et al. (2008) found that adult sex offenders could not understand the law and lacked sexual knowledge and social interaction skills. In addition, previous investigations by Day (1994) also noted that this population were changed by drugs and alcohol abuse (narcotics), family issues, neglect, violence and lack of self-control. However, these studies only offered clinical samples and did not offer controlled trials of participants who had learning disabilities. One of the major weaknesses in Day’s study is that the criteria for choosing participants according to individual IQs was not highlighted as compared to recent studies. For example, Heaton and Murphy (2013); Murphy et al. (2010) in their studies used psychological measures at baseline to ascertain performance IQs of the participants involved in the study. In other words, the relationship between a lower IQ and sex offending is not definitive (Blanchard et al. 1999). Consequently, due to such circumstantial evidence surrounding the causes of sex abusive behaviour, the current literature needs to be viewed with caution.
Sex Offenders Treatment Services Collaborative – Intellectual Disabilities (SOTSEC-ID)
Likewise, there is a dearth of literature that investigates the sexually abusive behaviour of men with learning disabilities. The existing studies investigate treatment programs offered to non-disabled counterparts in prisons (Murphy et al., 2010), and the prevalence of sexually abusive behaviour among people with learning disabilities is presumably underestimated (Brown and Thompson, 1997). Currently, most of the treatment programmes in the UK are coordinated by the Sex Offenders Treatment Services Collaborative – Intellectual Disabilities (SOTSEC – ID) in the form of cognitive treatment for men who have offended or at risk of offending.
For example, Glynis et al. (MISSING FROM REFERENCE LIST) investigated the treatment of 46 men who had engaged in sexually abusive behaviour and had been legally obliged to attend the program, or face further incarceration and their sentences being extended. The study found that none of the men who started the program committed further abusive behaviour such as non-contact behaviours. The sample size of 46 was reasonable compared to other previous studies of this program. A study by Heaton and Murphy (2013) had similar participants since it probed deeper into Murphy et al.’s research on the effectiveness of Cognitive Behavioural treatment. There were diverse characteristics of sexual abusive behaviour considering that participants had been chosen from different services, yet in all these studies the authors did not highlight the measures to preserve confidentiality and consent, which is normally a pivotal aspect of research studies and certainly adds to the academic rigour of them.
Previous, the vast majority of studies (Goodman et al., 2008; Hays et al., 2007) had a sample ranging from 4 to 16 participants and information which rendered the identity of the participants indeterminable. It is clear that participants drawn from the study by Murphy et al. would provide credible results considering their broad profiles and the large cross-section of sex offenders which they covered. However, in view of the sample size and the fact that participants were spread over different services a collection of all information would not be possible, which weakened the profile assembled of those involved in the study. Of course, bias was unavoidable considering that all these studies did not include a randomised trial, but there is a general consensus that a randomised trial would be difficult to achieve due to the perception of not allowing treatment for sexual behaviour to the non-abusive (Sakdalan and Collier, 2012).
There are several studies that investigate treatment programs for sex offenders, but debate about the efficacy and indeed the effectiveness of those treatments is being hampered by a short period in waiting for the follow up. There are few volumes that extended follow-up periods to three years as compared to the studies by Heaton and Murphy. In another comparison Goodman et al. (2008) and Lindsay (2002) also emphasised the significance of follow-up times to enable participants to disclose offences and abusive behaviours, consequently reducing the risk of sex offending and increasing community cohesion. The above evidence illustrates that studies that extend treatment programs have the opportunity to improve treatment outcomes for many years ahead on a longitudinal basis. Therefore, in practice healthcare professionals need to consider treatment programs based on evidence of follow-up years the research accommodated, and the extent in which that treatment improved offenders’ conditions, as ultimate indicators of the efficacy of the treatment programs.
Cognitive Behavioural Therapy (CBT) was employed by SOTSEC group to provide treatment for people with learning disabilities who are at risk of sex offending in changing their thought patterns and associations (Goodman et al., 2008; Murphy et al., 2010; Heaton and Murphy, 2013). The findings from the studies reported that although the participants accepted responsibility for sexual abusive behaviour, they also tended to blame the victim or past events. Both Murphy et al. and Heaton and Murphy reviewed data normality before analysis through the use of scales and questionnaires which made it superior to previous research that did not check the distribution of scores for empathy and attitude consistently, which are important elements of a sex offender’s rehabilitation. However, it is very difficult to ascertain the validity of such information considering that clinicians were collecting data as part of their clinical responsibilities and there is evidence that there was scarcity of resources for further collection of data during the follow-up period. Moreover, since the SOTSEC group did not prioritise data received for referrals and the data is limited, it means without a control group it would be difficult to prove the validity of the effectiveness of the treatment. Yet, there is no doubt that this form of treatment has the potential to improve the lives of people with learning disabilities who have sexual abusive behaviour, in getting them to realise the consequences of their actions and fulfil their potential.
This literature review comes to the main conclusion that there is tangible evidence to suggest that CBT can change the perceptions of sex offenders with learning disabilities towards their victims. In view of this, most studies did not address the efficacy of CBT delivered in practice by SOTSEC group due to a dearth of opportunities for follow-ups for unknown reasons, except studies (Hays et al., 2007; Murphy et al., 2010). Heaton and Murphy (2013) also had a substantial number of participants. Overall, the sample sizes were inclusive of participants who had sex convictions before and spread over different service providers. One explanation that needs to be explored further, however, is the lack of controlled trials that is prevalent in most studies that investigate offenders with learning disabilities, a component which could render the results inadequate. The studies above would have been more useful if they had increased the follow-ups up to a decade and attempted to prove that people with learning disabilities lack empathy as compared to offenders from the general population, thus explaining their possible irrational behaviours and blaming the victim, perhaps being unaware of their own role in the sexual abuse.
Equipping Youth to Help One Another Program (EQUIP)
The Equipping Youth to Help One Another Program (EQUIP) assists juvenile offenders from the general population who are incarcerated so that they can behave in an acceptable way in society through providing treatment that can address a deficiency in moral reasoning, distorted cognitions and lack of social skills, all of which are seemingly tratits of those with learning disabilities (Langdon, et al., 2012; Helmond et al., 2012; Stam et al., 2014). There is evidence (Kohlberg 1969, 1976, as cited in Langdon et al., 2013) that this theory was modified from a childhood perspective to suit teenagers and adults. Based upon the need to address a cognitive deficit, Gibbs (2003) further categorised the program into two levels, namely, ‘immature and mature’, and observed that unacceptable behaviour among young offenders is perpetuated by developmental moral reasoning. Despite such progress, a major drawback of this approach is that a few studies have investigated the EQUIP treatment from offenders with learning disabilities apart from valiant attempts by Langdon et al. (2013), Helmond et al. (2012), Stam et al. (2014) and Gibbs (2003).
Unlike the SOTSEC program that targets sex offenders with learning disabilities, Helmond et al. highlighted that the EQUIP approach can be applied to treat different offences in prisons and secured hospitals including sexually abusive behaviour, making it more wide ranging. The main themes covered in this program by a considerable number of studies are respectively: moral reasoning, cognitive distortions, anger and ability to solve problems. Beyond these themes there is evidence that the program can assist participants in a group to change negative attitudes by encouraging members to be responsible to each other, perhaps being in a position to work collaboratively and support each other. This interpretation overlooks the heterogeneity of the offences and anti-social members since a group approach is not helpful alone to overcome individual members with negative attitudes (Helmond et al., 2012), but could be a partial solution.
There is evidence that EQUIP is effective in assisting offenders who are in custody. Langdon et al. found that there is improvement in moral reasoning and participants were able to solve problems and find alternative solutions and as a result cognitive distortions were reduced, positive outcomes of the approach. However, studies with larger samples were characterised by problems in reducing recidivism (Lipsey, 2009), and as identified by Van Stam et al. (Put in YEAR of reference here) studies that normal consist of female samples yield larger improvements than their male counterparts. In view of this, there is evidence that lack of program integrity had an impact to the effectiveness of the EQUIP approach in most studies or due to incompetence during the implementation process (Helmond et al., 2012). For instance, in the study by Langdon et al., participants were few (n=7) though they were of a heterogeneous nature and their ages were not highlighted, demonstrating the investigators did not get enough information to interpret their findings and the sample size was insufficient anyway.
Some studies have attempted to use measurements to validate data analysis in a quantitative manner, thus providing more of a tangible conclusion. For example, the use of Socio-moral Reflection Measurement by Langdon et al. is not justified since it is used in people who are young and not adults; and there is no evidence that this tool can be effective in extrapolating it to offenders with learning disabilities. Of course, the HIT Questionnaire for cognitive distortions has been used among people with learning disabilities (Langdon et al., 2012), but there is also no evidence of its relevance and validity among this group of people. Whilst there is evidence that assessments have been done to measure the treatment integrity, a choice of quasi experimental designs has not been justified. Moreover, randomised control trials are difficult to implement considering that the participants were in prison and it is impossible to create a controlled group in such an environment (Farrington and Welsh, 2005).
Indeed, studies suggest that the moral judgement of younger people is less mature as compared to adults (Stam et al., 2014), although this may not be true of people with learning disabilities. While there are still a few studies that investigate the effectiveness of EQUIP among people with learning disabilities, most of the studies did not highlight the severity of the offences committed by the participant. Consequently, this leaves the EQUIP approach as being unable to be applied to offenders with learning disabilities. However, clinicians need to use the program with caution considering that it is generally used for sex offenders from mainstream settings.
In recent years, there has been an increasing amount of literature investigating the efficacy of the treatment options for sex offenders with learning disabilities (Murphy et al., 2007; Lindsay et al., 2013), although some were constrained by their small sample size, like Pritchard et al. (2011) and Goodman and Leggett (2011). Healthcare professionals need to pre-empt relevant factors for recidivism though there is evidence that this has not been undertaken in client groups with learning disabilities. Studies have reported that clinicians are not yet competent and prepared to predict recidivism among offenders in practice (Lindsay et al., 2004). Nonetheless, there are several studies that investigate recidivism within offenders from the general population compared to the client group with learning disabilities.
Surveys such as that conducted by Craig et al. (2005) reported that offenders with learning disabilities are likely to re-offend after treatment when compared to offenders from the general population. Day’s equitable study (1994) found groups that display strong traits of a lack of social skills, social exclusion and long periods of social disorders are inclined to carry out sex offences and will continue to be repeat offenders. Lindsay (2004) also reported predictive variables for recidivism at 53 percent and there is a probability that 73 percent are suspected of re-offending due to offenders’ unresponsiveness to treatment programs, possibly due to a lack of cognitive capacity. These statistics and findings were drawn from different samples and settings which when compared to the prevalence rate of recidivism as high or low among people with learning disabilities cannot be justified because of ambiguity and secrecy which shrouds reported and unreported offences. However, considering evidence that studies that investigate sex offenders with learning disabilities is generally low (Day, 1994; Murphy et al., 2010; Heaton and Murphy, 2013), it is hoped that in spite of the limitations of the studies above, they will be the foundation and catalyst for future studies.
There are some factors of recidivism which are easy to determine. For instance, Lindsay et al. (2004) investigated 52 male sex offenders who had mild to moderate learning disabilities and found that most of the variables had been highlighted before in studies that reviewed predictions in offenders from the general populations. The results that emerged from that study corresponded with evidence of re-offending including anti-social behaviour, repudiation of offences committed, and abuse from childhood and unresponsiveness to treatment programs. Such a corroboration infers that this is a reasonably reliable point. Despite this, Murphy et al. (2010) in their investigation of the effectiveness of treatment argued that childhood abuse, mental health issues and history in secured units were not correlated or associated with recidivism, although the fact that this was only a solitary study cats aspersions on such an argument. Indeed, Murphy et al. also proposed that people with learning disabilities but with autistic spectrum tendencies were likely to re-offend, a more specific argument, but one which is unsupported by other studies.
Limitations in the studies consulted throughout the composition of this literature review been identified highlighting the need for randomised control trials that investigate the effectiveness of sex offenders’ treatment with learning disabilities instead of depending on samples from the general population. The literature available focused on short follow-ups and there were variances in sample selections and criteria, with short follow-ups seemingly insufficiently reliable. There are inconsistencies in the prevalence and characteristics of sex offenders with learning disabilities (Murphy et al., 2010; Lindsay, 2002, 2004) and it is difficult to ascertain the effectiveness of treatment programmes and not easy to obtain ethical approval for no treatment controls studies (Lindsay, 2002).
Clinical evidence on sex offenders with learning disabilities depends on studies containing samples from mainstream settings and whose IQ surpasses 80 (90-110 is generally considered the normal range for people) (Murphy et al., 2010), and there are variations in participants involved by studies (Lindsay, 2004). It means that offenders with an IQ of less than 80 will not receive treatment (Murphy et al., 2010), which shows the discriminatory nature of some of these studies. However, since samples were selected from clinical and controlled perspective, there is evidence that the determination of IQ might not be credible or reliable. There was clearly data pertaining to the heterogeneity of participants from different studies, although the majority of the studies did not provide information for sex offenders without convictions. In truth, sample size did effect the study (Parahoo, 2006), as documented in this review, which shows studies that investigated the EQUIP program had significantly larger samples compared to the SOTSEC studies; with seemingly more positive outcomes as the risk of re-offending was reduced.
The EQUIP program has been designed to improve the deficits that had been observed amongst juveniles from the general population. However, the relevance of the program to people with learning disabilities is not clear, though there is reliable evidence that it is effective for young offenders from the general population and can be employed for different offences other than sexually abusive behaviour. Furthermore, unlike the SOTSEC that needed larger samples to improve treatment, research showed that the EQUIP program with small samples was effective as studies with larger samples, an admirable characteristic of the program (Stam et al., 2014; Lindsay, 2004). Parahoo (2006) stipulates that studies with large samples are expensive and time consuming and it is an ardusous prospect to gather data from participants. The main deficiency of the EQUIP program is that no study showed improvement in anger management (with patients as volatile as ever), which ratifies that that there is a direct correlation between participants’ characteristics and sample sizes, which will determine the effectiveness of the program.
In both programs, no study identified the severity or magnitude of the offences committed; which leaves readers uncertain as to which client group is relevant to a particular program. This would be useful information for a reader, although such a ploy does grant anonymity and leave the reader to be more objective. However, there is evidence that CBT, as applied by the SOTSEC group, can improve the effectiveness of treatment for sex offenders with learning disabilities as the intervening period between the culmination of the study and follow-ups are increased to monitor progress and increase validity/reliability. Ultimately, both programs are treatments which whilst still in their infancy, have some promise and potential as they can be used in both secured units and in the community. However, based upon the findings presented throughout the course of the paper, this literature review has come to the eventual conclusion that control trials are needed with people with learning disabilities.
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