4519.0 - Recorded Crime - Offenders, 2018-19 Quality Declaration 
Latest ISSUE Released at 11:30 AM (CANBERRA TIME) 06/02/2020   
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Explanatory notes

Introduction

This publication presents statistics about alleged offenders who were proceeded against by police during the 12 month reference period, for all states and territories. This includes information about the most serious offence, referred to as the principal offence, associated with an alleged offender (hereafter referred to as an "offender"). Statistics are also presented on the number of proceedings that police initiated in the form of court and non-court actions for all states and territories except Western Australia.


Data source

Statistics in this publication are derived from information about offenders collected by the ABS from administrative records held by the state and territory police agencies.


Scope and coverage

The scope of the collection includes all offenders, aged 10 years and over, who have been proceeded against by police during the reference period. Persons under the age of 10 are excluded from the collection as the minimum age of criminal responsibility in all Australian states and territories is 10 years.

All criminal offences where police agencies have the authority to take legal action against an individual are included, with some exclusions. Depending on the type and seriousness of the offence committed, police will either initiate a court or non-court action.

  • Court actions largely involve laying charges against an offender that must be answered in court. Offenders may be taken into custody, granted bail or issued with a summons for these charges pending an appearance in court. The proceeding may also be withdrawn or changed from a court to a non-court action.
  • Non-court actions comprise legal actions such as informal or formal cautions/warnings, conferencing, counselling, drug diversionary schemes, or the issuing of penalty notices, which do not require an appearance in court.


Exclusions

The scope excludes the following:
  • persons less than 10 years of age
  • organisations
  • offences that come under the authority of agencies other than state and territory police, such as Environmental Protection Authorities, etc.
  • proceedings initiated by the Australian Federal Police

Due to quality and/or comparability issues, or an inability to supply data to the ABS, the statistics presented in this publication exclude the following:
  • traffic offence information specifically related to ANZSOC division 14 traffic and vehicle regulatory offences and subdivision 041 dangerous or negligent operation of a vehicle
  • ANZSOC group 1523 breach of bail
  • Indigenous status data for offenders in Victoria, Western Australia and Tasmania
  • number of times proceeded against data and police proceedings data for Western Australia
  • method of proceeding data for South Australia and the Northern Territory


Reference period

The statistics in this collection relate to offenders proceeded against by police during the reference period 1 July 2018 to 30 June 2019. Additionally, selected statistics are available for 2008–09 to 2017–18.


Counting methodology

The main counting unit for this collection is the "offender", presented in data cubes 1 to 4. Data cube 5 uses "police proceedings" as the counting unit. The experimental family and domestic violence statistics in data cube 6 use both offenders and police proceedings as counting units.


Date of action

Data are compiled on the basis of the date that police initiated action, or proceeded against, an offender (e.g. the date the offender was charged, the date the offender was cautioned, etc.). The date the offender was proceeded against by police may not be the date when the offence occurred, or the date when the offender came to the attention of police. In some jurisdictions the data may reflect the date of record creation rather than date of action; however, this does not have a significant impact on the comparability of data across jurisdictions for offenders as there are no major lags between the two dates.


Offender counts

For the offender population, an offender is only counted once irrespective of how many offences they may have committed within the same incident or how many times they were dealt with by police during the reference period.


Police proceeding counts

For the police proceeding population, an offender may be counted more than once if proceeded against on separate occasions by police during the reference period. Data are presented for both court and non-court proceedings.


Principal offence

Offence information presented in this publication relates to the principal offence allegedly committed by an individual offender during the reference period. These statistics are not designed to provide a count of the total number of individual offences that come to the attention of police.

For the offender counts, where a single offence is processed by police during the reference period, the offender is assigned that offence as their principal offence. Where multiple offences are committed by an offender, they are assigned a principal offence using the ABS National Offence Index (NOI).

For the police proceeding counts, offenders who are proceeded against more than once in the reference period are assigned a principal offence for each separate date of police action. The following diagram provides an illustration of the assigning of a principal offence and the resulting counts for both populations.

Diagram: Displays examples of how a principal offence is assigned to the offender and proceeding populations.


Principal method of proceeding

For offender counts, the principal method of proceeding will be the method of proceeding associated with the principal offence assigned to that offender. For police proceeding counts, as offenders who are proceeded against more than once in the reference period are assigned a principal offence for each separate date of police action, they are also assigned the appropriate method linked to each principal offence.


Offender rates

Offender rates are expressed as the number of offenders per 100,000 of the ABS Estimated Resident Population (ERP). This method derives what are sometimes referred to as "crude rates". These rates generally accord with international and state and territory practice, and enable the comparison of the extent and type of offending across the individual states and territories, as well as a comparison over time.

Rates for the offender population are calculated using the ERP at the midpoint of the reference period (e.g. 31 December 2018 for the 2018–19 reference period). The ERP used in the calculation of these rates is for persons aged 10 years and over for all states and territories. Where rates are presented for a sex or age group, the ERP used in the calculation of the rates refers to the relevant sex or age group.

ERP estimates and projections applied for the Australian Capital Territory exclude Jervis Bay Territory. All estimates and projections for Australia exclude the external territories of Christmas Island and Cocos (Keeling) Islands.

For more information on the ERP, see Australian Demographic Statistics (cat. no. 3101.0).

Aboriginal and Torres Strait Islander offender rates

Aboriginal and Torres Strait Islander offender rates are expressed per 100,000 of the Aboriginal and Torres Strait Islander population aged 10 years and over. This method derives what are sometimes referred to as "crude rates". The offender rates presented in this issue are derived from the estimated population for the years 2009 to 2016, as well as the Series B projections of the Aboriginal and Torres Strait Islander population, from the ABS publication Estimates and Projections, Aboriginal and Torres Strait Islander Australians, 2006 to 2031 (cat. no. 3238.0).

These population estimates and projections are as at 30 June. An estimate for December 31 is then created by taking the average of the population estimates or projections at 30 June of that year and the following year. These figures are used to derive offender rates for each year.

Rates for the non-indigenous population are calculated using the total ERP of persons aged 10 years and over for each state or territory minus the projected Aboriginal and Torres Strait Islander population aged 10 years and over.

Age standardisation of offender rates

Age standardisation is a statistical method that adjusts crude rates to account for age differences between study populations.

There are differences in the age distributions between Australia's Aboriginal and Torres Strait Islander and non-indigenous populations, with the former having a much younger population. In 2001, the proportion of Aboriginal and Torres Strait Islander people aged 18 years and over was 55%, compared with 76% of non-indigenous people (and 75% of the total Australian population). The diagram below illustrates the differences in age distributions.

Estimated resident population, Australia – 30 June 2001
Pyramid graph displaying differences in age distribution of non-indigenous and Aboriginal and Torres Strait Islander populations.

Due to the differing age profiles, using crude rates to examine differences between Aboriginal and Torres Strait Islander and non-indigenous populations may lead to erroneous conclusions being drawn about variables that are correlated with age.

By making comparisons across age groups, we know that offender rates are negatively correlated with age. If we compare overall offender rates between Aboriginal and Torres Strait Islander and non-indigenous persons, it is likely that the offender rate in the Aboriginal and Torres Strait Islander population will be higher because of the larger proportion of young people in the Aboriginal and Torres Strait Islander population. Therefore, age standardised Aboriginal and Torres Strait Islander and non-indigenous offender rates have been presented in Table 23 of this publication.

The standard population used for age standardisation is the total Australian Estimated Resident Population at 30 June 2001. The standard population is revised every twenty five years; the next revision will be based on final data from the 2026 Census of Population and Housing.


Indigenous status

This publication only presents indigenous status data for New South Wales, Queensland, South Australia, the Northern Territory and the Australian Capital Territory. Based on ABS assessment, indigenous status data for other jurisdictions were not of sufficient quality and/or did not meet ABS standards for self-identification for national reporting in 2018–19.

Data about indigenous status for the Australian Capital Territory are included in this publication for the 2013–14 reference period onwards. In some instances, indigenous status is obtained by ACT Police without giving the offender the opportunity to self-identify. However, consultation with ACT Police showed that the proportion of records not obtained via self-identification was low, and the impact on the data was minimal.

As indigenous status is based on self-identification by the offender, identification is difficult where police proceed by way of a penalty notice as this method does not usually provide an opportunity for police to ask individuals to self-identify. This results in a large proportion of unknown values for indigenous status for offenders proceeded against via penalty notice. As such, indigenous status data in this publication exclude penalty notices. Therefore, offender counts and rates presented in this publication do not include all Aboriginal and Torres Strait Islander offenders proceeded against by police.

The proportion of all offenders proceeded against by police by way of a penalty notice during 2018–19 was:
  • New South Wales – 29%
  • Queensland – 9%
  • South Australia – 42%
  • Northern Territory – 44%
  • Australian Capital Territory – 5%

The use of penalty notices by police is most prevalent for theft, public order offences, offences against justice and miscellaneous offences. The removal of those offenders who were proceeded against via a penalty notice results in reduced offender counts and rates for these four offence divisions in particular.

The proportion of offenders with a 'not stated' indigenous status varies by offence type.


Proportion of offenders with unknown indigenous status(a), Selected states and territories, 2018–19

Principal offence
NSW
Qld
SA
NT
ACT

01 Homicide and related offences
8.7
2.5
6.0
0.0
0.0
02 Acts intended to cause injury
4.0
0.8
3.0
0.1
0.0
03 Sexual assault and related offences
3.6
2.4
1.9
0.0
0.0
04 Dangerous/negligent acts
20.8
1.1
3.2
0.0
0.0
05 Abduction/harassment
7.1
0.0
3.9
0.0
0.0
06 Robbery/extortion
0.3
1.1
4.5
0.0
0.0
07 Unlawful entry with intent
3.4
0.8
2.0
0.0
0.0
08 Theft(b)
8.3
1.1
10.7
0.9
0.0
09 Fraud/deception
8.9
0.7
7.9
3.2
0.0
10 Illicit drug offences
12.1
1.3
8.4
1.1
0.0
11 Prohibited/regulated weapons
10.7
0.6
7.4
0.0
0.0
12 Property damage and environmental pollution
9.8
1.2
6.7
0.0
0.0
13 Public order offences
14.3
3.6
20.8
0.0
0.0
15 Offences against justice
13.3
0.6
6.3
0.0
0.0
16 Miscellaneous offences
14.2
5.8
14.9
0.0
0.0
Total(c)
8.1
1.3
7.4
0.4
0.0

(a) Excludes offenders with a principal method of proceeding of penalty notices.
(b) Fare evasion excluded from theft for NSW, Qld & SA but included in total.
(c) Includes offenders with an unknown principal offence

Due to variation in the quality of South Australian data over recent reference periods, caution is recommended when interpreting data by indigenous status.


Classifications

The national classifications used to collect and produce data about offenders are:
  • Australian and New Zealand Standard Offence Classification (ANZSOC)
  • National Offence Index (NOI)
  • Method of Proceeding

Australian and New Zealand Standard Offence Classification (ANZSOC)

ANZSOC provides a uniform national framework for classifying offences across Australia and New Zealand for statistical purposes. The classification is a hierarchical structure allowing for varying degrees of detail to be published depending on the level of detail in the source information. Associated with the classification are coding rules which ensure that the counting of information is consistent across states and territories. For further information about ANZSOC refer to Australian and New Zealand Standard Offence Classification, 2011 (cat. no. 1234.0).

For ease of reading, some ANZSOC categories have been abbreviated throughout this publication as follows:
  • Dangerous or negligent acts endangering persons appears as 'Dangerous/negligent acts'
  • Abduction, harassment and other offences against the person appears as 'Abduction/harassment'
  • Robbery, extortion and related offences appears as ‘Robbery/extortion’
  • Unlawful entry with intent/burglary, break and enter appears as 'Unlawful entry with intent'
  • Theft and related offences appears as ‘Theft’
  • Fraud, deception and related offences appears as ‘Fraud/deception’
  • Prohibited and regulated weapons and explosives offences appears as ‘Weapons/explosives'
  • Offences against justice procedures, government security and government operations appears as 'Offences against justice'

National Offence Index (NOI)

The NOI (published in National Offence Index (cat. no. 1234.0.55.001)) is a tool which provides an ordinal ranking of offence categories in ANZSOC according to perceived seriousness in order to determine a principal offence. The purpose of the NOI is to enable the representation of an offender by a single offence in instances where multiple offences occur within the same incident or where offenders are proceeded against by police on more than one occasion in the reference period.

A revised NOI was released in 2018 to assign rankings to supplementary offence codes that were previously unranked in the 2009 version. The principal offence information presented for the 2017–18 reference period onwards is based on the 2018 version of the NOI with a minor modification for fare evasion offences.

The principal offence information presented in this issue for the reference periods 2008–09 to 2016–17 is based on the 2009 version of the NOI with a minor modification to add a ranking for ANZSOC group ‘0800 theft and related offences, not further defined’ to improve principal offence data for the Northern Territory. Due to this modification there is minimal impact on the data from the change to the 2018.

Fare evasion

Enforcement of laws/regulations on public transport is the responsibility of state/territory police and/or third party organisations. Data on offenders proceeded against by authorities other than police are out of scope of the Recorded Crime – Offenders collection. Due to the variance in police responsibility for public transport related offences across states and territories, an additional offence of fare evasion has been introduced to the principal offence categories to assist with the comparability of theft data across jurisdictions. The separation of this offence from the theft data impacts all data tables in which principal offence is presented. The data has been excluded from the theft and related offences division data but is included in the offender totals. The detailed fare evasion offence category is only presented in one table: Table 6 Offenders, Principal offence (divisions and selected subdivisions), States and territories, 2017–18 to 2018–19.

This action could only be applied for the 2014–15 reference period onwards. Users are advised not to compare data on offenders with a principal offence of theft to earlier reference periods as fare evasion cannot be separated from ANZSOC group 0829 theft (except motor vehicles), n.e.c. for the reference periods 2008–09 to 2013–14.

Please refer to notes for New South Wales, Victoria, Queensland and South Australia for other information on fare evasion data in those jurisdictions.

Method of proceeding classification

The method of proceeding describes the type of legal action (court or non-court) initiated by police against a person as a result of an investigation of an offence(s). The type of legal action may change as further investigation is undertaken by police. Not all changes made during the reference period may be reflected in this collection. The method of proceeding classification is a hierarchical classification. For details of the classification hierarchy refer to the Appendix.


Data comparability

National offender statistics are compiled in order to maximise comparability across states and territories. This collection has been designed to facilitate comparisons of states and territories through the application of common national statistical standards and counting rules. However, some legislative and processing differences remain. The following information highlights those processes unique to a jurisdiction that may have had an impact on the data for this collection. This may include differences in recording practices, legislation or policy to combat particular types of crime.

New South Wales

New South Wales legislation does not contain discrete offences of stalking, intimidation and harassment. As these offences cannot be disaggregated, offenders proceeded against for stalking, intimidation and harassment have been coded to ANZSOC group 0291 stalking. Therefore, this group may be overstated and ANZSOC division 05 abduction/harassment may be understated. Caution should be used when making comparisons with other states and territories.

From 1 May 2012 the NSW Police Force took over the role of policing the state's public transport network, through a dedicated Police Transport Command of 610 officers. This led to increases from 2012–13 in the number of offenders and proceedings in some ANZSOC categories, including theft (due to fare evasion), fraud and Public order offences. These offences are most often proceeded against by way of a penalty notice.

Verbal warnings and compliance notices were included for the first time in 2009–10 and resulted in an increase in non-court proceedings in NSW. They relate mainly to licensing enforcement (i.e. liquor, security industry, firearms). A verbal warning is a less formal process which informs the person that some breach of regulations need to be corrected. A compliance notice is a written warning with a stipulated time period within which the breach must be corrected.

Victoria

In Victoria infringement notices and on-the-spot fines for public transport fare evasion offences are predominantly issued by third party organisations. Offences issued by these organisations are out of scope of the Recorded Crime – Offenders collection. Infringement notices and on-the-spot fines may also be issued by Victoria Police (including Protective Service Officers); these are in scope of the Recorded Crime – Offenders collection.

Queensland

Queensland has a relatively high number of offenders with an unknown principal offence. This is due to the Queensland Police offender system containing reported offence details which are quite broad in their description. Where this occurs it may not be possible to determine the most serious offence, resulting in the principal offence being recorded as unknown.

A review was undertaken for the 2016–17 publication to determine if the number of offenders with an unknown principal offence could be reduced. This review found that a proportion of records with an unknown offence code should be coded to ANZSOC division 14 traffic and vehicle regulatory offences and so were out of the scope of the Recorded Crime – Offenders collection. These records have been excluded from the 2014–15 data onwards. Users are advised to exercise caution when making comparisons to data before 2014–15 as the total number of offenders for earlier years are overstated.

For public order offences, in comparison with other states and territories, Queensland Police make greater use of arrest, summons, cautions, and notices to appear as an action against an offender, and only limited use of penalty notices. This results in Queensland having the highest proportion of court actions of any state or territory.

Queensland data includes offenders proceeded against for fare evasion by the Queensland Police Service Rail Squad. Data on offenders proceeded against for fare evasion by TransLink Senior Network Officers or Queensland Rail Authorised officers are out of scope of the Recorded Crime – Offenders collection.

The issuing of infringement notices or 'e-ticketing' by Queensland Police for public nuisance offences commenced from 8 November 2010. These offences include: public nuisance, public urination, obstruct police officer (in relation to the aforementioned public nuisance or public urination) and contravene requirement of a police officer (in relation to stating correct name and address regarding the above). The introduction of this method of proceeding resulted in an increase in non-court proceedings in Queensland.

South Australia

New data management system

South Australia Police began recording offender data in a new data management system from November 2018. The 2018–19 offender data for South Australia includes data from the previous system for July to November 2018 and from the new system from November 2018 to June 2019. Users are advised to use caution when analysing this data, especially when comparing to earlier reference periods, as the impact of this change on the data is unknown.

Data by method of proceeding is currently not available for South Australia for 2018–19 due to the introduction of the new crime recording system.

Formal cautions/warnings

South Australia Police provided data for formal cautions/warnings and conferences for the first time in 2013–14. From 2013–14 to 2015–16 these methods of proceeding were only used for juvenile offenders. During the 2016–17 reference period South Australia police began issuing formal cautions and warnings to adult offenders for selected offences. The inclusion of this data for juvenile offenders in 2013–14 onwards and adult offenders in 2016–17 resulted in increases in the proportion of non-court actions for these reference periods.

Indigenous status

Due to variation in the quality of South Australian data over recent reference periods, caution is recommended when interpreting data by indigenous status.

In 2016–17, there were two key changes in the quality of the indigenous status data item:
  • Increased use of formal cautions and warnings as a method of proceeding in South Australia increased the number of offenders with an 'unknown' indigenous status from the 2016–17 reference period onwards.
  • South Australia police supplied indigenous status data for offenders proceeded against via drug diversions for the first time in the 2016–17 reference period, which reduced the number of records with an ‘unknown’ indigenous status by approximately 97%. This increased the total number of Aboriginal and Torres Strait Islander offenders and non-indigenous offenders for South Australia when compared with data from previous years. In addition, the number of Aboriginal and Torres Strait Islander offenders and non-indigenous offenders with a principal offence of illicit drugs offences have increased due to the inclusion of indigenous status data for drug diversions when compared with data from earlier reference periods.

The introduction of the new crime recording system in November 2018 resulted in a reduction in the proportion of offenders with an unknown indigenous status for 2018–19 as it includes a mandatory field to record this information.

Proportion of offenders with unknown indigenous status(a), South Australia

Principal offence
201516
201617
201718
201819

01 Homicide and related offences
0.0
0.0
5.8
6.0
02 Acts intended to cause injury
1.8
5.0
6.0
3.0
03 Sexual assault and related offences
2.6
4.2
3.4
1.9
04 Dangerous/negligent acts
7.8
10.3
19.5
3.2
05 Abduction/harassment
2.5
8.6
7.1
3.9
06 Robbery/extortion
1.6
2.2
1.4
4.5
07 Unlawful entry with intent
2.9
3.4
5.0
2.0
08 Theft(b)
2.5
15.2
24.1
10.7
09 Fraud/deception
4.1
12.1
17.9
7.9
10 Illicit drug offences
70.0
2.2
13.0
8.4
11 Prohibited/regulated weapons
3.1
12.9
21.4
7.4
12 Property damage and environmental pollution
2.7
8.5
13.6
6.7
13 Public order offences
2.2
27.1
45.5
20.8
15 Offences against justice
2.3
8.2
14.1
6.3
16 Miscellaneous offences
3.1
13.9
24.2
14.9
Total(c)
21.2
8.2
15.5
7.4

(a) Excludes offenders with a principal method of proceeding of penalty notices.
(b) Fare evasion excluded from theft included in total.
(c) Includes offenders with an unknown principal offence

Unlinked databases

Caution should be exercised when interpreting counts of offenders and proceedings with a principal offence of illicit drug offences for South Australia as the data may be overstated. Data relating to offenders issued with cannabis expiation notices and drug diversions are stored on separate infringement databases and this information cannot be linked to other databases that store information about offenders. As the databases cannot be linked, if an offender was proceeded against for multiple offences during the same reference period then they may be counted more than once, resulting in an over count of the total number of offenders, rates and police proceedings for South Australia.

General expiation notices may be issued for public order offences and offences against justice and are stored on an infringement database that cannot be linked with other police databases that contain information about offenders. As a result, offenders with a principal offence of public order offences or offences against justice may be overstated as an offender may be counted more than once if they were proceeded against for multiple offences during the same reference period.

Fare evasion

Infringement notices for public transport fare evasion offences in South Australia can be issued by the Public Transport Safety Branch (part of South Australia Police) or Adelaide Metro Prescribed Officers. This publication contains data on police proceedings only, as such, infringements issued by the metro officers are out of scope of this collection.

Western Australia

Western Australia Police utilise two separate crime recording systems for the Recorded Crime – Offenders collection. Data from both systems undergo a matching process to enable the production of offender statistics and associated demographic and offence information presented within this publication. Users should be aware that data may be slightly overstated as a result of the identifier matching process.

Data about police proceedings are unable to be successfully matched between the two separate crime recording systems used by Western Australia Police. Therefore data relating to police proceedings for Western Australia are not included in this publication. This affects Tables 16 and 17 and precludes the production of national data about police proceedings or the number of times an offender was proceeded against by police.

Western Australia Police applied a number of revisions to their offence coding in the 2017–18 and 2018–19 data for national statistical purposes. This impacts on a range of offences and results in the data by offence being not comparable to previous reference periods.

Tasmania

For the 2016–17 cycle, a review of Tasmanian ANZSOC mappings identified that a number of offences related to boating were being incorrectly mapped to division 16 miscellaneous offences, rather than being identified as division 14 traffic and vehicle regulatory offences (and therefore out of the scope of the Recorded Crime – Offenders collection). Corrected data was provided for the 2015–16 and 2016–17 reference years. Users are advised to exercise caution when making comparisons to data before 2015–16 as the data for earlier years are overstated.

Minor coding changes were made by Tasmania Police in 2012–13, with the most notable impact being the movement of some offenders previously coded to ANZSOC group 1312 criminal intent to group 1121 unlawfully obtain or possess regulated weapons/explosives and group 1122 misuse of regulated weapons/explosives.

Further coding changes were made by Tasmania Police in 2011–12, with the most notable impact being the movement of some offenders previously coded to ANZSOC group 1322 liquor and tobacco offences to group 1541 resist or hinder government official (excluding police officer, justice official or government security officer) and group 1562 resist or hinder police officer or justice official.

From 4 April 2011, Tasmania Police were only able to proceed against youth offenders for minor drug offences under the Youth Justice Act 1997, rather than give Illicit Drug Diversion Initiative cautions and diversions. This resulted in an increased number of court actions for youth offenders for illicit drug offences between 2009–10 and 2010–11.

For the 2010–11 Recorded Crime – Offenders collection, Tasmania Police undertook a review of their ANZSOC mappings and implemented coding changes that impacted on some principal offence divisions for the 2009–10 and 2010–11 reference periods, most notably division 04 dangerous/ negligent acts, division 07 unlawful entry with intent, division 08 theft and division 13 public order offences. For details about these coding changes, refer to notes in the 2010–11 issue of this publication.

Northern Territory

An internal review of recording practices and systems undertaken by the Northern Territory Police in 2015 highlighted concerns with the method of proceeding data and, as such, data on police proceedings for the Northern Territory were not included in the 2014–15 and 2015–16 publications. Due to system constraints, an accurate method of proceeding (court or non-court action) could not always be determined. Subsequent investigation determined that the issue was limited to the method of proceeding data and that total police proceedings data is of sufficient quality for publication. Total police proceedings data for NT are included in the police proceedings data cube but not by method of proceeding.

Northern Territory Police are unable to provide cautions or warnings data, as these methods are largely used informally and are not recorded in the primary proceedings system. It is estimated that there are very few instances where such methods are used and therefore the impact on the data presented in this publication are minimal.

There are a small proportion of offenders that come into contact with police who are unable to provide their exact date of birth. In these situations, where only a birth year is provided, police may allocate a nominal birth date or alternatively, police may record the offender's date of birth as unknown.

Australian Capital Territory

Criminal infringement notices (CINs) were introduced on 24 December 2009 for a range of minor public order offences, including defacing premises, urinating in public, failing to comply with noise abatement direction and consuming liquor in a prescribed public place. CINs are aimed at having an immediate deterrent effect on an offender while providing an alternative to court action. These offences are not recorded on the primary Australian Capital Territory police recording system.

Caution should be exercised when interpreting data on counts of offenders and proceedings for the ACT. As the CINs data are recorded on a separate system, this information cannot be linked to other databases that store information about offenders. Therefore, if an offender had been proceeded against for multiple offences recorded across the separate systems then that offender would be counted more than once. This may result in an over count of the total number of offenders, rates and police proceedings for the Australian Capital Territory.

Additionally, CINs data do not contain unique identifiers attached to the records. Therefore, if an offender had received multiple CINs during the reference period they may be counted multiple times. This may result in an over count of the total number of offenders, rates and police proceedings for the Australian Capital Territory.


Confidentiality

The Census and Statistics Act 1905 provides the authority for the ABS to collect statistical information, and requires that statistical output shall not be published or disseminated in a manner that is likely to enable the identification of a particular person or organisation. This requirement means that the ABS must ensure that any statistical information about individuals cannot be derived from published data.

To minimise the risk of identifying individuals in aggregate statistics, a technique is used to randomly adjust cell values and summary variables. This technique is called perturbation and was applied to the Recorded Crime – Offenders collection for the first time for the 2013–14 release. Perturbation involves small random adjustment of the statistics and is considered the most satisfactory technique for avoiding the release of identifiable statistics while maximising the range of information that can be released. These adjustments have a negligible impact on the underlying pattern of the statistics.

After perturbation, a given published cell value will be consistent across all tables. However, the sum of components of a total will not necessarily give the same result as the published total in a particular table. As such, proportions may add to more or less than 100%. Readers are advised to use the published totals rather than deriving totals based on the component cells.

Cells with relatively small values may be proportionally more affected by perturbation than large values. Users are advised against conducting analyses and drawing conclusions based on small values.

Perturbation has been applied to the data presented in this publication. Previously, a different technique was used to confidentialise these data and therefore there may be small differences between historical data presented in this publication and those published in previous issues of this publication.


Revisions

Revised data for 2017–18 were received from Victoria, Western Australia and Tasmania during the preparation of this publication. Users are advised against making comparisons between data in this issue and in previous issues of the publication, as data may not be directly comparable.

A full set of data on offenders proceeded against via penalty notices in 2017–18 were not available from Victoria Police for the last publication. A complete dataset has since been supplied and revised data for 2017–18 is presented in this publication.

Western Australia Police applied a number of revisions to their offence coding for national statistical purposes. Revised data for 2017–18 is presented in this publication to allow comparison with the new 2018–19 data.

In July 2019 the ABS published the backcast population estimates (for the period 2006 to 2015) for Aboriginal and Torres Strait Islander persons, as well as Aboriginal and Torres Strait Islander population projections (for the period 2016 to 2031) in Estimates and Projects, Aboriginal and Torres Strait Islander Australians, 2006 to 2031 (cat. no. 3238.0). As a result, offender rates for both the Aboriginal and Torres Strait Islander population and the non-indigenous population in this publication for the years 2008–09 to 2017–18 have been revised.

Total offender rates were also revised for the years 2011–12 to 2015–16 with the finalised rebased population estimates released using the results of the 2016 Census of Population and Housing. Refer to the earlier section on rates for information on how these are calculated.


Comparisons to other ABS data

Recorded Crime – Victims

There are strong links between victims and offenders recorded by police in their administrative systems. Once a victim is recorded by police an investigation may ensue which could result, although not always, in an offender being proceeded against by police. However, there are a number of limitations in comparing the Recorded Crime – Offenders collection and the Recorded Crime – Victims collection.
  • Data cannot be directly linked.
  • Counting units vary as victims may be counted more than once throughout the reference period.
  • The reference period used in the victims collection is based on the calendar year, while the offenders collection is based on the financial year.
  • Police may detect a crime without it being reported by a victim.
  • ‘Victimless' crimes, such as illicit drug offences or regulatory offences are excluded from the victims collection.
  • Statistics about victims of assault are not comparable across all states and territories due to differences in police procedures; consequently national data are not published.

Despite these differences, broad comparisons can be made between the two collections. For more detailed information about data comparability in relation to the Recorded Crime – Victims collection and more generally about using administrative and survey data, refer to the information paper, Measuring Victims of Crime: A Guide to Using Administrative and Survey Data, June 2011 (cat. no. 4500.0.55.001).

For more information about the victims collection, refer to Recorded Crime – Victims, Australia (cat. no. 4510.0).

Criminal Courts

Data relating to the number of court action proceedings in Recorded Crime – Offenders are not strictly comparable to the number of defendants sourced from the Criminal Courts collection.
  • Not all court actions initiated by police will proceed to a criminal court as police proceedings may be withdrawn or changed to other legal actions during the course of an investigation.
  • A defendant appearing in a criminal court in Australia may be prosecuted via charges initiated by authorities other than state and territory police.
  • There are lags between when the police initiate action and when a criminal court finalises a defendant's case.

For more information about criminal courts refer to Criminal Courts, Australia (cat. no. 4513.0).


Additional data

Other tables may be able to be produced on request to meet individual user requirements. For further information, contact the National Information and Referral Services on 1300 135 070 or email <client.services@abs.gov.au>.