Best use of psychological treatment resources has long exercised the minds of service managers. The question of how many psychologists were needed in particular settings gave rise to early efforts to tackle this issue eg. mental health, educational settings. But the question is impossible to answer without considering others — what can psychologists contribute in a setting, how effective are they, how many will they have to service?
Initial efforts to determine how many psychologists were needed were not empirically based, but relied on authority — someone regarded as an expert in an area eg. a medical superintendent in a mental health setting, was asked for an opinion. The Minister of Justice initially asked the Secretary for Justice for an opinion. Later, the Assistant Secretaries for Penal Institutions and Probation were asked their opinions by the then Secretary for Justice, and later still, external reviewers asked managers of prisons, community corrections and others for their opinions.
This approach is understandable, given the lack of empirical data at the time, but a shaky basis for such important decisions. No matter how senior or experienced such authorities, their opinions will be influenced by factors having nothing to do with psychological knowledge, skills or effectiveness.
Next came efforts to bring some empirical evidence to the issue, based on the size of population to be serviced. A mental health service would calculate how many patients passed through its system each year and how many were likely to need psychological services, and arrive at the number of psychologists required.
This was a step in the right direction, but relied too much on the authority method in deciding how many were likely to need psychological services. The ultimate decision was not backed up by empirical data. Views on what psychologists could contribute and how effectively were matters of opinion rather than fact.
That opinion was often based on demand for psychological treatment, the third traditional approach. Given current emphasis on meeting client requirements, achieving client satisfaction and so on, a demand-based approach is again topical.
Demand may come from those spontaneously seeking psychological help, or through intermediaries by way of referrals eg. in the corrections setting, referrals from prison and community corrections staff. Quite often, neither the client nor the intermediary understands what a psychologist can do or how effective they might be. It is an idiosyncratic approach, shown to result in demands that bear little relationship to needs, or to what psychologists can achieve.
Special needs as a basis for allocating treatment resources
Criminal behaviour is often attributed to alcohol and other substance buse, mental illness and intellectual disability. If these do cause crime, psychological treatment resources should be directed to psychologists with expertise in these areas, and this means of allocating psychological treatment resources still goes on in some criminal jurisdictions around the world. It is not, however, a satisfactory way of allocating treatment resources.
Alcohol and other drug abuse
Numerous studies show a relationship between alcohol and other drug abuse, and crime. Prevalence rates range from 20 to almost 80 percent, depending on the measures used eg. self-report, reports by others (police, friends, relations etc), or laboratory assay, and the type of crime(s) committed (Pritchard 1977, Monohan 1983, Collins 1981, Roizan 1981, McGlothin 1985, Guze 1976, Maden et al 1991). Sensitive laboratory assay tends to yield higher percentages (Pallone 1990). Little information is available on the New Zealand corrections population, but what there is tends towards higher prevalence rates (Whitney 1992, Brinded et al 1996, Zampese 1998, Bakker 1991).
Despite the prevalence of alcohol and/or drug abuse among convicted offenders, a causative link has not been established. All that can be said is that crime is associated with alcohol and drug abuse. The strongest argument for a causal link is with crimes committed to support a 'habit.' But even then, craving drugs is a motive rather than a cause of crime(s).
Alcohol and other drug abuse, and their relationship to crime, tend to be lumped together in the literature, yet reconviction studies show a distinction. Several international studies have found illegal drug abuse to be highly predictive of reconvictions, and alcohol abuse only weakly, or not at all (Motiuk & Brown 1993, Andrews, Bonta & Hoge 1990, Gendreau, Little & Goggin 1996). The same is true for New Zealand offenders (Anderson & Riley 1991, McLean 1998).
Mental illness
Prevalence rates for mental illness in corrections populations depend on the definition of mental illness employed, and what measure(s) are used to detect it. These range from an arresting officer’s opinion and pencil and paper psychological tests, to full psychological or psychiatric assessment. Not surprisingly, the literature reports rates of from four to 70 percent.
Higher rates are likely to be reported when the definition includes 'antisocial personality disorder,' since signs/symptoms of that diagnosis can be detected in most people with a criminal history. Lower rates are reported mainly when the definition is limited to serious psychiatric illnesses, such as psychoses (Rabkin 1979, Monahan 1983, Guze 1976, Sosowsky 1978, Cocozza et al 1978, Snow & Briar 1990, Gunn et al 1978 & 1991, Wierson et al 1992, Brinded et al 1996, Malmquist 1990, Harris et al 1991, Feder 1991, Zampese 1998). Interestingly, a large proportion of offenders with signs of mental illness have criminal histories pre-dating their illness, which suggests the mental illness may not be associated with the offending (Gunn et al 1991). Furthermore, several international studies have shown there is no relationship between mental illness and re-offending (Motiuk & Brown 1993, Motiuk & Porporino 1989, Gendreau et al). This has also been shown for New Zealand offenders (Anderson & Riley 1991, McLean 1998).
Intellectual disability
Studies in various countries over long periods have shown the intelligence level of corrections populations approximate that of the general population ie. about five percent will have a degree of intellectual disability; most will have only a mild degree; very few will have severe to profound intellectual disability (Jones & Combes 1990, Lund 1990, Denkowski & Denkowski 1985, Hayes & McIlwain 1988, Gunn et al 1991, Snow & Briar 1990, Wierson et al.1992). Research shows the same to be true of New Zealand (Black and Hornblow 1973, Markland 1979, Love 1981). The most recent New Zealand survey, based on a strict definition of intellectual disability, gave the prevalence in prisons as between 0.3 and 0.37 percent (Brandford 1997).
Some authors favouring a biological basis for crime argue that low intelligence substantially influences criminal behaviour. This is still contentious, but even if correct, given the strong evidence of normal distribution of intelligence among corrections populations, accounts for only a fraction of crime.
Conclusion on special needs groups
Special needs groups are often treated in the literature and in practice as if they were homogenous. Yet they differ in many ways. There are many distinct diagnoses of mental illness; alcohol and drug abuse varies in frequency and extent; intellectual disability ranges from mild to profound. Individuals within groups vary as to type of offence(s), age, race, socio-economic factors, marital status, abilities, skills and so on. Crucially, they differ in their likelihood of reconviction.
Use of special needs as a basis for allocating Psychological Service treatment resources must focus on why the individual is under Department of Corrections jurisdiction, rather than on the service appropriate to those needs. These people are offenders, and while the department must, humanely, consider their special needs, it is their offending behaviour that is crucial to the aim of reducing re-offending.
Special needs group members differ in their likelihood of reconviction. The Psychological Service will contribute most to the aim of reducing re-offending by directing treatment resources to individuals highly likely to be reconvicted, rather than on the sole basis of special needs.
