TECHNICAL NOTE CHANGES TO OFFENCE DATA


INTRODUCTION

1 From this issue, offence data for 2009 and onwards presented in this publication will largely be compiled and presented according to revised offence classifications. In 2009, the Australian Standard Offence Classification (ASOC), 2008 (Second edition) (cat. no. 1234.0), and the National Offence Index (NOI) 2009 (cat. no. 1234.0.55.001), were introduced into the Prisoner Census collection. The classification changes affect the most serious offence for sentenced prisoners, and the most serious charge for unsentenced prisoners. Previous issues of this publication were based on the Australian Standard Offence Classification (ASOC) 1997 (cat. no. 1234.0) and the 2002 National Offence Index (NOI).

2 ASOC08 was adopted to provide a more contemporary classification system, taking into account significant legislative changes that have occurred at state and territory level since the first edition was released, as well as satisfying emerging user requirements for offence data. NOI was updated largely to reflect changes made to ASOC.


IMPACT ON 2009 DATA AND TIME SERIES

3 All jurisdictions implemented ASOC08 and NOI09 for the provision of offence data for the 2009 Prisoner Census, with the exception of Western Australia and Queensland. ASOC97 and NOI02 will continue to be used for these jurisdictions. Introducing ASOC08 and NOI09 involved remapping local jurisdictional offence codes to the new classification. This process has had some level of impact to the time series, and to comparability across jurisdictions given some have not yet implemented these changes.

4 The total number of offence divisions has not changed between the two versions of ASOC, and only minor changes have been made to division titles. However, ASOC08 includes three additional subdivisions and 16 additional groups. A few subdivisions and groups have been moved and are now inclusions in other subdivisions and groups. Table 1 below provides a summary view of the major expected changes between divisions. Changes have also been made to the inclusions and exclusions of the classification to improve coding; refer to Appendices 1 and 2. Further detailed information relating to the conceptual changes between ASOC97 and ASOC08 is available in Australian Standard Offence Classification (ASOC), 2008 (Second edition) (cat. no. 1234.0).

Table 1 Expected major ASOC changes(a)
	Expected major change
ASOC Division
01 Homicide and related offences	nil	-
02 Acts intended to cause injury	+	ASOC: From Division 16 - Inclusion of stalking.
	+	NOI: Relative change in rankings of serious assault resulting in injury (0211) and aggravated robbery (0611) - expect increase in assaults if co-occur with aggravated robbery, and a decrease in robbery counts.
03 Sexual assault and related offences	+	ASOC: From Division 13 - Inclusion of child pornography and sexual servitude offences (potentially from Divisions 05, 06, 13 and 16).
04 Dangerous or negligent acts endangering persons	+	NOI: Expect increase where driving under the influence of alcohol or other substance (0411) and dangerous or negligent operation (driving) of a vehicle (0412) co-occurs with other offences such as 0611, 0711, 0812 and 0829, as NOI rankings have moved from 89 and 90 to 37 and 38 respectively.
05 Abduction, harassment and other offences against the person	+	ASOC: From Division 16 - Inclusion of harassment and private nuisance and threatening behaviour.
	+	NOI: Expect some increase in Abduction/kidnapping (051) and Deprivation of liberty/false imprisonment (052) where aggravated assault has been remapped to 0212. ASOC 0511 and 0521 are ranked above 0212 on the NOI, and are likely to be selected as the most serious offence when offences are remapped and co-occur.
	-	NOI: Conversely, may decrease where 0531 co-occurs with offences in Divisions 07, 08, 09 or 11, or groups 1211, 1542, 1559, 1561, 1612, 1631, 1694 or 1695. Has moved from rank 39 to 82.
06 Robbery, extortion and related offences	-	ASOC: From Divisions 05, 06, 13 and 16 - Decrease due to the exclusion of sexual servitude offences.
	-	NOI: Expect decrease where co-occurs with assault offences as serious assault resulting in injury is now ranked above aggravated robbery in the NOI.
07 Unlawful entry with intent	-	NOI: Expect decrease where co-occurs with driving under the influence of alcohol or other substance (0411) and dangerous or negligent operation (driving) of a vehicle (0412) as these have moved from NOI rankings of 89 and 90 to 37 and 38 respectively.
08 Theft and related offences	+	ASOC: From Division 09 - Expect increase due to inclusion of fare evasion. Further possible increases where Theft from retail premises (0823) co-occurs with other offences, as it has moved from a NOI ranking of 138 to 74 (impacts on some co-occurring offences in Divisions 10, 13, 15 and 16).
	-	NOI: May be offset by decreases where theft co-occurs with driving under the influence of alcohol or other substance (0411) and dangerous or negligent operation (driving) of a vehicle (0412), as these have moved from NOI rankings of 89 and 90 to 37 and 38 respectively.
09 Fraud, deception and related offences	-	ASOC: Removal of fare evasion (to Division 08) and bribery involving government officials (to Division 15).
10 Illicit drug offences	nil	-
11 Prohibited and regulated weapons and explosives offences	nil	-
12 Property damage and environmental pollution	nil	-
13 Public order offences	-	ASOC: Removal of child pornography and sexual servitude (both to Division 03) and conspiracy offences to other divisions (Not all conspiracy offences have moved out of Division 13 with some recoded to 1312).
14 Traffic and vehicle regulatory offences	nil	-
15 Offences against justice procedures, govt. security and operations	+	ASOC: From Division 16 - Inclusion of immigration offences; from Division 09 - Bribery involving government officials.
16 Miscellaneous offences	-	ASOC: Removal of harassment and private nuisance (to Divisions 02 or 05), threatening behaviour (to Division 05), and immigration offences (Divisions 03 or 15).
(a) All divisions other than Division 01 and Division 13 may experience some increase due to inclusion of conspiracy offences with actual offences. Further changes may have also impacted on Division counts in addition to those major changes represented here.

Analysis of impacts

5 Four jurisdictions (New South Wales, Victoria, Tasmania and the Northern Territory) supplied 2009 data coded to both ASOC97 and ASOC08, which enabled an assessment of the impact of the changes to the classification on the prisoner census data. It should be noted that as part of implementation, jurisdictions also rectified a number of codes that were miscoded in previous years.

6 Table 2 shows the results of this analysis, providing estimated changes to the total division level movement summed across those four jurisdictions that provided dual-coded data. The table provides a count of prisoners at 30 June 2009 based on classifying most serious offence/charge to ASOC97 and ASOC08. The differences between the two populations largely reflects the impact of the change from ASOC97 to ASOC08 and some changes as a result of correcting miscoding errors in ASOC97.

Table 2 Estimated impact of classification changes, prisoners 2009(a), combined selected states and territories(b)
			Divisional change(c)
	Prisoners (ASOC97)	Prisoners (ASOC08)
ASOC Division	no.	no.	no.	%
01 Homicide and related offences	1 553	1 560	7	0.5
02 Acts intended to cause injury	3 066	3 276	210	6.8
03 Sexual assault and related offences	1 828	1 887	59	3.2
04 Dangerous or negligent acts endangering persons	266	294	28	10.5
05 Abduction, harassment and other offences against the person	138	176	38	27.5
06 Robbery, extortion and related offences	1 650	1 550	-100	-6.1
07 Unlawful entry with intent	1 616	1 614	-2	-0.1
08 Theft and related offences	811	813	2	0.2
09 Fraud, deception and related offences	540	531	-9	-1.7
10 Illicit drug offences	2 106	2 134	28	1.3
11 Prohibited and regulated weapons and explosives offences(d)	246	204	-42	-17.1
12 Property damage and environmental pollution(d)	189	170	-19	-10.1
13 Public order offences(d)	271	156	-115	-42.4
14 Traffic and vehicle regulatory offences	894	895	1	0.1
15 Offences against justice procedures, govt. security and operations	1 690	1 683	-7	-0.4
16 Miscellaneous offences	204	125	-79	-38.7
Total	17 068	17 068	. .	. .
. . not applicable
(a) Includes rectification of miscoding of records not a direct result of changes to ASOC.
(b) New South Wales, Victoria, Tasmania and the Northern Territory.
(c) Represents difference directly as a result of ASOC08, and rectification of miscoding errors.
(d) There were substantial impacts in these divisions due to the rectification of miscoding errors in some jurisdictions, in addition to classification changes.

7 Table 2 shows that some prisoner counts have moved between most serious offence/charge categories as a result of the classification and rectification of miscoding changes, however it also illustrates that the total number of prisoners for the combined four states and territories has not been impacted by the classification changes. Four divisions (05, 11, 13 and 16) recorded changes of 15% or greater, however this was largely due to small numbers. All other divisions recorded changes below 15%. The impact of these changes overall to offence data for the four combined jurisdictions has been relatively small.

8 Table 3 below provides an overview of the changes to the most serious offence/charge counts for all prisoners from 2008 to 2009 with and without the classification changes. To illustrate, the table shows that the number of prisoners in 2009 increased by 6% from 2008 (from 27,615 prisoners in 2008 to 29,317 prisoners in 2009). The rise in prisoner numbers has not been impacted by the classificatory changes. However, given subdivision and group changes have occurred within divisions as a result of changes to ASOC08 and NOI09, the allocation of the most serious offence/charge for prisoners in some cases will be different than if they were classified to ASOC97 and NOI02. The correction of miscoding errors in 2009 also could have resulted in changes between divisions, however these were not significant in most cases. For example, the table shows that the number of prisoners with a most serious offence/charge of acts intended to cause injury increased by 13%. Approximately 4% of this change can be attributed to changes to the classification and/or miscoding rather than an actual increase in prisoners for this offence type. Excluding these classification changes, the estimated increase in prisoners for this offence type from 2008 to 2009 would be approximately 8% rather than 13%.

9 However, the interpretation of these movements is further complicated. South Australia was unable to provide a dual-coded file, and the Australian Capital Territory was only able to supply a partial dual-coded file, therefore all classificatory impacts could not be measured. Furthermore, the most serious offence/charge data for Queensland and Western Australia still reflect counts based on ASOC97 rather than ASOC08. Had these jurisdictions implemented ASOC08 the movements across divisions would have altered. It is anticipated that the level of movements across offence types would be similar to the larger jurisdictions. Caution should therefore be exercised when using these estimates as the accuracy of the level of movement cannot be fully ascertained as the movements do not include changes that would have occurred if Queensland and Western Australia had moved to ASOC08 and do not reflect any measures for South Australia and the Australian Capital Territory. The data should be used as a guide to interpret the level of movements of most serious offence/charge counts between 2009 and earlier years and between jurisdictions.

Table 3 Indicative impact of classification changes, prisoners, 2009, Australia
	All prisoners		Change from 2008 to 2009
	2008	2009			Classification impacts ASOC97 to ASOC08(a)	Indicative change (excluding classification impacts) 2008 to 2009
ASOC Division	no.	no.	no.	%	%	%
01 Homicide and related offences	2 712	2 717	5	0.2	0.3	-0.1
02 Acts intended to cause injury	2 713	5 638	630	12.6	4.2	8.4
03 Sexual assault and related offences	3 411	3 633	222	6.5	1.7	4.8
04 Dangerous or negligent acts endangering persons	448	585	137	30.6	6.3	24.3
05 Abduction, harassment and other offences against the person	212	284	72	34.0	18.9	15.1
06 Robbery, extortion and related offences	2 682	2 791	109	4.1	-3.7	7.8
07 Unlawful entry with intent	3 138	3 209	71	2.3	-0.1	2.3
08 Theft and related offences	1 159	1 290	131	11.3	0.2	11.1
09 Fraud, deception and related offences	871	876	5	0.6	-1.0	1.6
10 Illicit drug offences	2 885	3 217	332	11.5	1.0	10.5
11 Prohibited and regulated weapons and explosives offences	251	278	27	10.8	-16.7	27.5
12 Property damage and environmental pollution	354	368	14	4.0	-5.4	9.3
13 Public order offences	300	212	-88	-29.3	-38.3	9.0
14 Traffic and vehicle regulatory offences	1 411	1 414	3	0.2	0.1	0.1
15 Offences against justice procedures, govt. security and operations	2 407	2 504	97	4.0	-0.3	4.3
16 Miscellaneous offences	359	276	-83	-23.1	-22.6	-0.6
Total	27 615	29 317	1 702	6.2	. .	. .
. . not applicable
(a) Classification impacts are based on the change observed across the four combined jurisdictions who provided dual-coded extracts, and include changes due to miscoding.

10 The following tables provide a summary view of the estimated impacts of implementing the classificatory changes by comparing individual selected state and territory 2009 prisoner data by most serious offence/charge for each division, comparing counts based on what the data would have looked like using ASOC97 and what the data are now reflecting using ASOC08. These differences also include changes as a result of miscoding. These tables are only presented for jurisdictions who implemented ASOC08 in 2009 and were able to supply dual coded files. Further tables are available on the ABS website for these same selected states and territories showing the indicative impacts of these classification changes to the prisoner movements of the most serious offence/charge data between 2008 and 2009 for New South Wales, Victoria, Tasmania and the Northern Territory. These tables should only be used as a guide when comparing state and territory offence data.

Table 4 Estimated impact of classification changes, prisoners 2009(a), New South Wales
			Divisional change(b)
	Prisoners (ASOC97)	Prisoners (ASOC08)
ASOC DIVISION	no.	no.	no.	(%)
01 Homicide and related offences	849	856	7	0.8
02 Acts intended to cause injury	2 006	2 166	160	8.0
03 Sexual assault and related offences	931	981	50	5.4
04 Dangerous or negligent acts endangering persons	170	187	17	10.0
05 Abduction, harassment and other offences against the person	107	138	31	29.0
06 Robbery, extortion and related offences	1 187	1 123	-64	-5.4
07 Unlawful entry with intent	1 067	1 061	-6	-0.6
08 Theft and related offences	514	514	-	-
09 Fraud, deception and related offences	341	339	-2	-0.6
10 Illicit drug offences	1 448	1 476	28	1.9
11 Prohibited and regulated weapons and explosives offences(c)	193	152	-41	-21.2
12 Property damage and environmental pollution	103	99	-4	-3.9
13 Public order offences(c)	234	129	-105	-44.9
14 Traffic and vehicle regulatory offences	640	638	-2	-0.3
15 Offences against justice procedures, govt. security and operations	1 158	1 146	-12	-1.0
16 Miscellaneous offences	179	122	-57	-31.8
Total	11 127	11 127	. .	. .
. . not applicable
- nil or rounded to zero (including null cells)
(a) Includes rectification of miscoding of records not a direct result of changes to ASOC.
(b) Represents difference directly as a result of ASOC08, and rectification of miscoding errors.
(c) There were substantial impacts in these divisions due to the rectification of miscoding errors, in addition to classification changes.

Table 5 Estimated impact of classification changes, prisoners 2009(a), Victoria
			Divisional change(b)
	Prisoners (ASOC97)	Prisoners (ASOC08)
ASOC DIVISION	no.	no.	no.	(%)
01 Homicide and related offences	532	532	-	-
02 Acts intended to cause injury	557	605	48	8.6
03 Sexual assault and related offences	694	695	1	0.1
04 Dangerous or negligent acts endangering persons	62	63	1	1.6
05 Abduction, harassment and other offences against the person	26	29	3	11.5
06 Robbery, extortion and related offences	378	345	-33	-8.7
07 Unlawful entry with intent	447	459	12	2.7
08 Theft and related offences	250	256	6	2.4
09 Fraud, deception and related offences	163	159	-4	-2.5
10 Illicit drug offences	584	584	-	-
11 Prohibited and regulated weapons and explosives offences	48	47	-1	-2.1
12 Property damage and environmental pollution(c)	57	40	-17	-29.8
13 Public order offences	22	20	-2	-9.1
14 Traffic and vehicle regulatory offences	107	107	-	-
15 Offences against justice procedures, govt. security and operations	404	406	2	0.5
16 Miscellaneous offences	19	3	-16	-84.2
Total	4 350	4 350	. .	. .
. . not applicable
- nil or rounded to zero (including null cells)
(a) Includes rectification of miscoding of records not a direct result of changes to ASOC.
(b) Represents difference directly as a result of ASOC08, and rectification of miscoding errors.
(c) There were substantial impacts in this division due to the rectification of miscoding errors, in addition to classification changes.

Table 6 Estimated impact of classification changes, prisoners 2009(a), Tasmania
			Divisional change(b)
	Prisoners (ASOC97)	Prisoners (ASOC08)
ASOC DIVISION	no.	no.	no.	(%)
01 Homicide and related offences	69	69	-	-
02 Acts intended to cause injury	102	103	1	1.0
03 Sexual assault and related offences	58	64	6	10.3
04 Dangerous or negligent acts endangering persons	9	21	12	133.3
05 Abduction, harassment and other offences against the person	-	3	3	-
06 Robbery, extortion and related offences	53	52	-1	-1.9
07 Unlawful entry with intent	49	44	-5	-10.2
08 Theft and related offences	33	28	-5	-15.2
09 Fraud, deception and related offences	27	25	-2	-7.4
10 Illicit drug offences	27	28	1	3.7
11 Prohibited and regulated weapons and explosives offences	-	-	-	-
12 Property damage and environmental pollution	16	16	-	-
13 Public order offences	8	-	-8	-100.0
14 Traffic and vehicle regulatory offences	39	39	-	-
15 Offences against justice procedures, govt. security and operations	39	40	1	2.6
16 Miscellaneous offences	3	-	-3	-100.0
Total	535	535	. .	. .
. . not applicable
- nil or rounded to zero (including null cells)
(a) Includes rectification of miscoding of records not a direct result of changes to ASOC.
(b) Represents difference directly as a result of ASOC08, and rectification of miscoding errors.

Table 7 Estimated impact of classification changes, prisoners 2009(a), Northern Territory
			Divisional change(b)
	Prisoners (ASOC97)	Prisoners (ASOC08)
	no.	no.	no.	(%)
01 Homicide and related offences	103	103	-	-
02 Acts intended to cause injury	401	402	1	0.2
03 Sexual assault and related offences	145	147	2	1.4
04 Dangerous or negligent acts endangering persons	25	23	-2	-8.0
05 Abduction, harassment and other offences against the person	4	5	1	25.0
06 Robbery, extortion and related offences	32	30	-2	-6.3
07 Unlawful entry with intent	53	50	-3	-5.7
08 Theft and related offences	14	15	1	7.1
09 Fraud, deception and related offences	9	8	-1	-11.1
10 Illicit drug offences	47	46	-1	-2.1
11 Prohibited and regulated weapons and explosives offences	4	4	-	-
12 Property damage and environmental pollution	13	15	2	15.4
13 Public order offences	6	6	-	-
14 Traffic and vehicle regulatory offences	108	111	3	2.8
15 Offences against justice procedures, govt. security and operations	89	91	2	2.2
16 Miscellaneous offences	3	-	-3	-100.0
Total	1 056	1 056	. .	. .
. . not applicable
- nil or rounded to zero (including null cells)
(a) Includes rectification of miscoding of records not a direct result of changes to ASOC.
(b) Represents difference directly as a result of ASOC08, and rectification of miscoding errors.