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Selected offender profiles

The ABS does not yet publish offender data but is working towards developing an offender-based collection. Until this new dataset becomes available, examination of offenders and some of their characteristics is possible only by compiling data from other sources. This chapter brings together information on the profiles of offenders from three sources: police annual reports from the three jurisdictions which release offender statistics; the national police custody survey; and the Drug Use Monitoring in Australia program.

Alleged offenders

Official data on gender and age of alleged offenders are published by the police services of Victoria, Queensland and South Australia and refer to persons who have allegedly committed a criminal offence and who have been processed for that offence. Police statistics on alleged offenders are not available from the remaining states and territories.

This chapter presents data on alleged offenders classified according to gender and age. These data should be interpreted with caution as they only reflect police processing of offenders in three states and may not be representative of national trends. The main purpose is to give an indicative view of major issues relating to offenders, in particular the following:

  • What is the age at which offender rates peak?
  • Is the age pattern of male offender rates similar to or different from that of females?
  • Are female offender rates on the increase?
  • How does the age pattern of male offenders compare with that of females?

The number of alleged offenders does not equate to the number of distinct offenders during a year because police may take action against the same individual for several offences, or the individual may be processed on more than one occasion for the same offence type. Nor does it equate to the total number of crimes cleared during a given period, as one crime may involve more than one offender.

Throughout this chapter, the terms 'offender' and 'offender rate' refer to alleged offenders and the alleged offender rate.

The term 'total offender population' refers to the total number of (not necessarily distinct) individuals aged 10 years and over processed by police for any of the offences listed below in the states of Victoria, Queensland and South Australia. The rates of total offenders included in the tables and graphs in this chapter are calculated relative to the total population aged 10 years and over in these jurisdictions (Reference 2). The data are presented on a financial year basis.

The offender data included here are for the following major types of crime:

  • homicide and related offences (murder, attempted murder, manslaughter, infanticide and driving causing death);
  • assault;
  • sexual assault;
  • robbery;
  • unlawful entry with intent;
  • motor vehicle theft;
  • other theft (theft from a vehicle, theft from shops, other theft); and
  • fraud and deception-related crime.

Source: References 8-10

Age

Persons aged 15 to 19 years are most likely to be processed by police for the commission of a crime. In 2003-04 the offending rate for persons aged 15 to 19 years was more than four times the offender rate for the remainder of the population (6496 per 100,000 and 1475 per 100,000 respectively).

Figure 55 : Offenders by age, rate per 100,000 relevant persons, 1995-96 to 2003-04

Figure 55

  • In the past nine years offender rates have been subject to change over time.
  • Between 1995-96 and 2003-04, offender rates reached a maximum in 1999-2000 and have since declined for most age categories. The one exception was the rate for 10-14 year-olds, which peaked in 1995-96.
  • Declines were greatest among the 15-19 and 20-24 year age groups.
  • Throughout the past nine years offender rates were consistently lowest among persons aged 25 and over and highest among those aged 15 to 19.

Source: References 2 and 8-10

Gender

In 2003-04, Victoria, Queensland and South Australia processed a total of 169,280 offenders, of whom 134,915 were male and 34,365 were female. Females made up 22% of all offenders in 1995-96 and 20% in 2003-04.

Figure 56 : Offenders by gender, rate per 100,000 relevant persons, 1995-96 to 2003-04

Figure 56

  • Males are almost four times more likely than females to be identified as offenders. In 2003-04, the rate of offending by males was 3019 per 100,000 compared with a rate of 749 by females.
  • Offending rates for both males and females were highest between 1999 and 2001 and have since declined.

Source: References 2 and 8-10

Figure 57 : Male offenders by age, rate per 100,000 relevant persons, 1995-96 to 2003-04

Figure 57

  • Since 1995-96, the rate for male offenders has consistently been highest among the 15-19 year-old age group, at between 10,400 and 13,500 per 100,000 relevant population.
  • Rates were also high during this period among males aged 20-24, ranging between 6400 and 9200 per 100,000 relevant population. Males in the other age groups offend at much lower rates, generally under 4500 per 100,000.
  • Since 1999-2000 there has been a significant decrease in rates for male offenders in the 10-14, 15-19 and 20-24 age groups. Offender rates among males aged 25 and over changed comparatively little over this period.
  • In the period 1995-2004, for 10-14 and 15-19 year-old males, offender rates were highest in 1995-96. For the other age groups offender rates peaked in 1999-2000.

Source: References 2 and 8-10

Figure 58 : Male offenders by offence type, rate per 100,000 relevant persons, 1995-96 and 2003-04

Figure 58

  • Male offender rates were highest for the offences of other theft, assault and unlawful entry with intent.
  • Rates were lowest for robbery, sexual assault and homicide in both 1995-96 and 2003-04.
  • Most rates were similar in both years, but other theft declined.

Source: References 2 and 8-10

Figure 59 : Female offenders by age, rate per 100,000 relevant persons, 1995-96 to 2003-04

Figure 59

  • Similar to male offending rates, rates among females since 1995-96 have been consistently highest among the 15-19 year-old age group.
  • Since 1995-96 there has been an overall decrease across most age groups in rates of female offending, with the largest decrease occurring in the 15-19 year-old age group.
  • Between 1995 and 2004 for all age groups the female offender rate peaked in the period 1999-2001 and has since declined. However, the decline was not statistically significant among females aged 25 plus.

Source: References 2 and 8-10

Figure 60: Female offenders by offence type, rate per 100,000 relevant persons, 1995-96 and 2003-04

Figure 60

  • Female offender rates were highest for other theft, fraud/deception-related crime and assault and lowest for sexual assault, robbery and homicide in both 1995-96 and 2003-04.
  • Compared with 1995-96, in 2003-04 female offending rates increased for assault, motor vehicle theft, and unlawful entry with intent. The rate for assault rose by 33%, compared with 4% for males during this period.
  • Rates for other theft dropped by 37%.

Source: References 2 and 8-10

Juveniles

There are differences among the states in the definition of a juvenile. Data in this section include alleged offenders aged between 10 and 17 years.

Figure 61 : Juvenile and adult offenders, rate per 100,000 relevant persons, 1995-96 to 2003-04

Figure 61

  • Juvenile rates of offending are 50% higher than rates for adults.
  • The offender rate among juveniles declined from 4092 per 100,000 juveniles in 1995-96 to 3023 in 2003-04. The largest decline was between 2000-01 and 2002-03 at 20%.
  • The adult rate increased from 1820 per 100,000 adults in 1995-96 to 2105 in 2000-01 before dropping to 1685 per 100,000 adults in 2003-04.

Source: References 2 and 8-10

Figure 62 : Juvenile offenders by gender, rate per 100,000 relevant persons, 1995-96 to 2003-04

Figure 62

  • There were differences in the patterns of offending by male and female juveniles.
  • Rates of male juvenile offending have dropped by 27% since 1995, with a 19% drop in the past three years.
  • Female juvenile offending rates have generally declined, with an initial increase followed by a decline in the past four years.
  • There has been a slight increase in the percentage of juvenile offenders who are female, from 21% in 1995-96 to 23% in 2003-04.

Source: References 2 and 8-10

Figure 63 : Juvenile offenders by offence type, rate per 100,000 relevant persons, 1995-96 and 2003-04

Figure 63

  • Juvenile offender rates were similar in 1995-96 and 2003-04 for the offences of homicide, assault, and robbery.
  • Juvenile offender rates have declined for the offences of motor vehicle theft, unlawful entry with intent, and other theft.

Source: References 2 and 8-10

The national police custody survey

In October 2002 the national police custody survey was conducted for the fourth time by the Australian Institute of Criminology. As this survey is conducted over a one month period it provides only a snapshot in time. In focusing on detainees in police custody it provides a glimpse of selected characteristics of persons who are detained by police. It is important to note that a substantial proportion of persons detained by police are not necessarily arrested and charged with an offence.

Figure 64 : Indigenous and total custody rates, per 100,000 relevant persons, 1988, 1992, 1995 and 2002

Figure 64

  • The total custody rate decreased 13% over the time of the four surveys.
  • The Indigenous custody rate fluctuated over the four surveys but has decreased overall from 3539 in 1988 to 2028 per 100,000 in 2002.
  • The level of over-representation of Indigenous Australians in police custody has declined from 28.6 in 1988 to 17 in 2002.

Source: References 2 and 21

In 2002 women accounted for 23% of Indigenous persons in custody, whereas they accounted for only 14% of non-Indigenous persons in custody.

Juveniles (those aged less than 18) were also over-represented, accounting for just under 13% of all custody incidents involving Indigenous people and just under 7% of all custody incidents involving non-Indigenous people.

Figure 65 : Reasons for being in custody (a)

Figure 65

(a) Excludes not stated (n=38).

(b) Protective custody incidents were almost all for public drunkenness. Persons taken into protective custody for public drunkenness were in NSW, WA, SA, NT, Tas and the ACT where public drunkenness is not an offence.

(c) Includes questioning.

(d) Includes awaiting transit to/from court and awaiting extradition and breaches of court orders and fine defaults, where the person was not arrested.

  • Arrests made up 52% of reasons for people being in police custody. Being under investigation was the next most common reason, accounting for 16%.
  • The least common reason for being in police custody was for remand purposes, accounting for only 2%.

Source: Reference 21

Figure 66 : Most serious offence associated with being in custody, number, by Indigenous status

Figure 66

  • Among the 52% of persons arrested, most non-Indigenous people were in police custody for property offences.
  • Indigenous people were mostly in police custody for public order, violence and property offences.
  • The least common offence for which people were held in police custody was drug offences. Many detainees charged with drug offences, however, are also charged with more serious offences.

Source: Reference 21

Drug use by offenders

Police detainees

The AIC's Drug Use Monitoring in Australia (DUMA) program monitors illicit drug use among police detainees in several sites across Australia on a quarterly basis. DUMA provides a reasonable and independent indicator of drug-related crime within these specific areas. Two methods are used to obtain this information: a questionnaire and a urine sample. As an ongoing monitoring system, DUMA enables law enforcement to track long-term changes in drugs and crime. 2004 was the fifth year of data collection and the second year of the second phase of data collection. Funding was provided by the Australian Government Attorney-General's Department and South Australian Attorney-General's Department.

By 2002 seven sites were being monitored: East Perth in Western Australia, Southport and Brisbane City in Queensland, Bankstown and Parramatta in New South Wales, and Adelaide City and Elizabeth in South Australia. Brisbane City, Adelaide City and Elizabeth began participating in 2002.

Data are collected quarterly and presented in the following figures as annual averages.

The percentage of police detainees testing positive to methylamphetamine (speed), cocaine, cannabis and heroin differs across the seven sites.

Source: Reference 22

Figure 67 : Percentage of adult male police detainees testing positive to methylamphetamine, 1999-2004

Figure 67

  • Methylamphetamine use has increased at all long-term sites since monitoring began in 1999.
  • The first noticeable increase in methylamphetamine use occurred in 2000.
  • Methylamphetamine use is consistently lower in Sydney than other sites.
  • Of the sites participating since 2002, Adelaide is the only site not to show an upward trend, although all three sites are high relative to the pre-existing sites, other than the East Perth site.

Source: Reference 22

Figure 68 : Percentage of adult male police detainees testing positive to cocaine, 1999-2004

Figure 68

Note: The scale for this chart is considerably different from that of the other three charts as the percentages involved are comparatively small.

  • The proportion testing positive to cocaine was extremely low at all sites during 1999 and 2000.
  • In 2001 there was an increase observed at the two NSW sites, but they declined in 2002 and in 2003.
  • Compared with 2003, in 2004 the proportion testing positive increased at all sites except Southport, although the numbers are small.

Source: Reference 22

Figure 69 : Percentage of adult male police detainees testing positive to cannabis, 1999-2004

Figure 69

  • The percentage of detainees testing positive to cannabis ranged from 37% (Bankstown) to 72% (Elizabeth).
  • Between 1999 and 2004 the percentage of detainees testing positive to cannabis was relatively unchanged at most sites.
  • The percentage of detainees testing positive to cannabis was highest at the two South Australian sites of Adelaide and Elizabeth.
  • Bankstown was the only site to register a marked downward trend, while Elizabeth has registered an increase in the three years of monitoring.

Source: Reference 22

Figure 70 : Percentage of adult male police detainees testing positive to heroin, 1999-2004

Figure 70

  • The two NSW sites registered a substantial decline in the percentage of detainees testing positive to heroin in 2001. However, since then there has been a slight upward trend.
  • The percentage of detainees testing positive to heroin at the East Perth site declined steadily between 2000 and 2004, from 18% to 8% of detainees.
  • All other sites have remained relatively stable in the percentage of detainees testing positive to heroin.

Source: Reference 22

Figure 71 : Percentage of adult male police detainees testing positive to any drug, 1999-2004 (a)

Figure 71

(a) 'Any drug' is defined as testing positive to cannabis, heroin, methylamphetamine, cocaine or benzodiazepines.

  • Sites routinely have around 60-80% of detainees testing positive to any drug.
  • With the exception of Bankstown and Parramatta, the percentage of detainees testing positive to any drug has remained roughly steady or increased since monitoring began at each site.
  • The drop in detainees testing positive for any drug at Bankstown and Parramatta sites could largely be explained by the drop in heroin at these sites and the drop in cannabis at Bankstown.

Source: Reference 22

Figure 72 : Percentage of adult male police detainees testing positive to selected drugs at the four long-term sites, 1999-2004

Figure 72

  • Between 1999 and 2004 the percentage of detainees testing positive to any drug or to cannabis has remained relatively steady.
  • Heroin use has decreased over the period. Most of this decrease was registered between 2000 and 2001.
  • Methylamphetamine use increased until 2001 but has since then levelled off.
  • The percentage of detainees testing positive to cocaine increased until 2001 but has since then decreased.

Source: Reference 22

Figure 73 : Percentage of adult male police detainees testing positive to a drug, by most serious offence, 2004

Figure 73

(a) Methylamphetamine

(b) Benzodiazepines

  • Detainees charged with a property offence were more likely to test positive to drugs than violent offenders.
  • Overall, 83% of all offenders charged with property offences and 65% of those charged with violent offences tested positive to a drug.

Source: Reference 22