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Illicit drug use, offending and gender

A number of recent Australian studies have found strong links between illicit drug use and offending among both adult and juvenile prisoners (Johnson 2004; Makkai & Payne 2003; Prichard & Payne 2005). In one of these studies, 62 percent of the adult male prisoners reported regular drug use prior to their current imprisonment; cannabis, amphetamines and heroin were the three most commonly used drug types, with around one-third reporting poly drug use (ie using 2 or more drug types; Makkai & Payne 2003). For the majority of male prisoners, offending tended to precede illicit drug use; however, those who became addicted to drugs reported more frequent property offending (Makkai & Payne 2003). Similarly, a study based on police detainees found that heavy illicit drug use was associated with higher levels of property offending (Bradford & Payne 2012).

An Australian study of female prisoners found rates of regular and poly drug use similar to those among male prisoners (Johnson 2004). The three most commonly used drug types were also the same but the proportion of women using cannabis was lower than men (40% of women cf 53% of men), while the proportions using amphetamines (37% of women cf 31% of men) and heroin (27% of women cf 21% of men) were higher. In addition, 15 percent of female prisoners had been using illegally obtained benzodiazepines prior to their imprisonment. Women’s’ illegal drug use had either preceded their criminal offending or occurred within the same year (Johnson 2004).

High levels of illicit drug use have also been found among Australian police detainees (Loxley & Adams 2009). This study also found some gender differences in the types of drugs used prior to current arrest—cannabis, alcohol and ecstasy were used by larger proportions of male detainees, while amphetamines, heroin, other opiates and benzodiazepines were used by larger proportions of female detainees (Loxley & Adams 2009). Women reported regular use of illicit drugs prior to their first arrest, while men’s substance use was more likely to be limited to alcohol and cannabis prior to their first arrest (Loxley & Adams 2009).

These findings suggest a strong relationship between illicit drug use and offending, as well as gender differences in the type of drugs used and the order of initiation into illicit drug use and offending.

Mental disorder, offending and gender

Recent Australian studies have found very high rates of mental disorders among imprisoned offenders (AIHW 2012; Butler & Allnutt 2003; Kraemer, Gately & Kessell 2009). For example, Butler and Allnutt (2003) found that 74 percent of adult prisoners in New South Wales had experienced a mental disorder during the prior 12 months, compared with 22 percent of people in the overall Australian population. Similarly, 88 percent of young offenders in juvenile detention in New South Wales were found to have symptoms consistent with at least one clinical disorder (Allerton & Champion 2003). In both of these prison-based studies, female prisoners had higher prevalence rates of mental disorder than male prisoners. Among adult prisoners, 86 percent of women had experienced a mental disorder in the previous 12 months compared with 72 percent of males (Butler & Allnutt 2003). Among young people in custody, a larger percentage of girls than boys had clinical disorders with severe, moderate and mild symptoms—61 percent of girls compared with 48 percent of boys had disorders with symptoms in the severe range, 89 percent of girls and 67 percent of boys had disorders with symptoms in the moderate range, and 78 percent of girls and 58 percent of boys had disorders with symptoms in the mild range (Allerton & Champion 2003). Gender differences in mental disorders have also been found in the general Australian population but the prevalence rates are much lower than among prisoners. For example, a recent survey of the Australian population found that 22 percent of women had experienced a mental illness in the preceding year, compared with 18 percent of men (ABS 2007). Higher proportions of women than men had experienced anxiety and affective disorders, while the converse was found for substance abuse disorders (ABS 2007).

Comorbidity, offending and gender

In addition to high prevalence rates of mental disorders, many offenders have been found to have comorbid mental disorders and substance use disorders. For example, a recent study found that over half of male prisoners and two-thirds of female prisoners with a substance use disorder also experienced a comorbid disorder (Butler & Allnutt 2003). Similarly, studies based on detainees suggest high prevalence rates of comorbidity (Baksheev, Ogloff & Thomas 2010; Heffernan et al. 2003), with female detainees more likely to report a comorbid psychiatric condition in addition to a substance use disorder (Heffernan et al. 2003). Increasingly, the issue of comorbidity among people in the criminal justice system is being highlighted for attention from research, treatment and prevention perspectives (Byrne & Howells 2002; Forsythe & Adams 2009; Jones & Crawford 2007; Smith & Trimboli 2010; Teesson & Proudfoot 2003).

A number of studies have suggested that poor mental health may be a contributing factor to criminal offending, either independently or comorbidly with substance abuse (Mullen 2001; Ogloff et al. 2007). This view is supported by evidence from a recent study of prisoners released from NSW jails, which found those with comorbidity had significantly higher rates of reoffending than those with mental disorder alone or substance use alone (Smith & Trimboli 2010). Comorbidity has also been identified as particularly salient for female offenders (Byrne & Howells 2002). Andrews and Bonta (2010), on the other hand, have argued strongly that mental disorder is not functionally related to offending behaviour. They argue that the only role mental disorder plays is to limit an offender’s ability to respond to rehabilitation programs that aim to reduce reoffending (Andrews & Bonta 2010).

The importance of criminal justice system-based mental health information

Whether mental disorder is functionally related to offending behaviour, or mediated by other factors such as substance abuse, or related to an offender’s ability to respond to rehabilitation efforts, there is enough evidence to suggest that it is an important factor to measure. Accurate data is imperative to enable research to further elucidate the nature of the relationship between mental disorders and offending. This is particularly the case as mental disorders are amenable to treatment. If there is a causal relationship between mental disorders and offending, and/or if mental disorders limit the ability of an offender to make the behavioural changes targeted by rehabilitation programs, then treatment may be expected to have a crime reduction effect.

The recent establishment of specialist or problem-solving courts specifically set up to deal with people whose offending is related to substance dependence or mental disorder are testament to both community and government concern that traditional criminal justice system approaches are inadequate for dealing with drug dependent and/or mentally disordered offenders (Payne 2006).

Specialist courts are based on the theory of therapeutic jurisprudence, which posits that legal decisions, roles and processes have therapeutic, anti-therapeutic or neutral impacts (Wexler 1990). In general, Australian courts operate within an adversarial paradigm. By contrast, courts with a therapeutic mandate are based on the principles of trust, procedural fairness and narrative competence, place a high value on relationship and relational stability, and recognise the important roles played by emotions in cognition and behaviour (Freiberg 2002). Australian drug courts are designed to achieve therapeutic outcomes—reducing drug dependency and associated criminal activity through treatment and rehabilitation programs that are closely monitored by the court (Freiberg 2002; Payne 2006). Similarly, specialist mental health courts and mental health liaison services aim to reduce offending by people who have been identified as mentally impaired (Bradford & Smith 2009; Payne 2006). These initiatives, as well as others such as the Compulsory Drug Treatment Prison in New South Wales, forensic hospitals and community-based offender treatment programs all aim to reduce offending by targeting mental disorders (Birgden & Grant 2010; Butler & Allnutt 2003; Henderson 2003; Justice Health & Forensic Mental Health Network 2011). Quality and timely data on mental disorders, illicit drug use and offending would enhance the evidence base to inform these and other services and programs.

Sources of information about mental health, illicit drug use and crime

Large-scale epidemiological studies such as the National Survey of Mental Health and Wellbeing (ABS 2007) provide information about prevalence rates of disorders and related health data for the whole Australian population. However, particular subsets of the population can sometimes be difficult to identify; for example, it would not be possible to identify offenders (as questions about criminal offending are not asked), so it is not possible to compare the mental health of offenders with that of the general population using such studies.

Most information regarding specific populations is yielded by research studies conducted on a ‘one off’ basis, such as the prisoner studies referred to earlier (eg Johnson 2004; Makkai & Payne 2003; Prichard & Payne 2005 among others) or the study conducted with arrestees in a Queensland watchhouse (Heffernan et al. 2003). Such studies are designed to seek very specific information from a specified group of people at a particular time.

Some issues, however, are prone to change or are known to differ between locations. In these cases, one-off studies are limited in their ability to provide information that can be generalised across time or location. For example, illicit drug markets have been found to be dynamic and localised (Raskin White & Gorman 2000) so any information collected in any one place or point in time may be expected to date quickly and may not be indicative of other locations. To meet this challenge, there are two major sources of regular national data collection on illicit drug use and drug markets in Australia—the Illicit Drug Reporting System (IDRS) and the DUMA program. Both the IDRS and DUMA are monitoring programs that comprise ongoing data collection about specific aspects of drug use and drug markets. The IDRS is a national survey of injecting drug users, coordinated by the National Drug and Alcohol Research Centre and provides information on the use, price, purity and availability of heroin, methamphetamine, cocaine and cannabis (Stafford & Burns 2009). The DUMA program is coordinated by the AIC and collects information on drug use, drug purchasing and offending from people who have been detained in police custody (Makkai 1999; Sweeney & Payne 2012).

While the illicit drug use and drug market information generated by IDRS and DUMA is quite wide ranging, neither has, to date, incorporated the collection of comprehensive or regular mental health information. Both collections have included some mental health-related questions but these have typically been limited to a specific aspect of mental health and/or been incorporated on an occasional basis. For example, the IDRS periodically asks respondents whether they have experienced any mental health problems in the six months prior to interview and if so, what types of problems they have experienced (de Graaff & Bruno 2007). The DUMA survey has regularly incorporated questions about admission to a psychiatric hospital and recent psychoactive medication use, and on two occasions questions about psychological distress were included (Forsythe & Adams 2009; Schulte, Mouzos & Makkai 2005).

The fact that different studies utilise different measures of mental health makes it difficult to make comparisons between studies and highlights the conceptual issue of what is actually measured by each approach. The AIC recently reviewed the mental health measures incorporated into its DUMA program with a view to improving the quality of the mental health information collected. The DUMA program already incorporates detailed information about both offending and drug use, so the addition of mental health data provides a unique opportunity to further elucidate the relationships between these three factors. A unique feature of the DUMA program is that it is ongoing and therefore has the facility to measure change. The experiences from the review are used throughout this report to illustrate some of the complexities and challenges inherent in the measurement of mental health in criminology research.

Related links

Measuring mental health in criminology research: Lessons from the Drug Use Monitoring in Australia program: