12 Data definitions and groupings

On this page12.1 Major management category
12.2 Glossary of major management category terms12.3 Gender
12.4 Age
12.5 Ethnicity
12.6 Offence prioritisation
12.7 Offence grouping
12.8 Data mart
12.9 Concept diagram of directives issued

12.1 Major management category

The offender inventory system enforces a one-day-one-status requirement on each offender, so that each offender’s timeline is partitioned into discrete and non-overlapping episodes of management. Major management categories are defined with a trumping or rank order. The order of precedence in the hierarchy of management is the most expensive or significant management category on any day. The rule allows examination of the balances and transitions from one category to another category in a way that assists the analysis of the business of the Department of Corrections and the careers of offenders.

One of the features of the resulting timeline data set is that it provides for analysis of offender flows and balances, such that opening balances always equal closing balances and there is certainty that no change to an offender’s status has been inconsistently treated. Should an offender status change be overlooked, then it will become obvious that the offender is being inappropriately classified. One of the consequences is that the numbers do not necessarily provide all the detail covered in other reports.

The full table with rank order for major management categories can be found here. An overview of the descriptions used is given below. It should be noted that the definitions are necessarily loose to accommodate a span of history with changing terminology and legislation.

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12.2 Glossary of major management category terms
Term UsedMeaning an episode of management where:
Prison Sentenced

The prisoner is sentenced to a custodial episode. This sentence may be regarded as one of:

Indeterminate: The prisoner is sentenced to a life or preventive detention custodial episode with no set release date; any release requires an order from the New Zealand Parole Board.

Long-term: The prisoner is sentenced to a custodial episode of fixed length, with the longest sentence chain (after taking into account cumulative and concurrent directives) being greater than two years. Currently the law requires these longer-term sentenced offenders to serve at least one third of the imposed term, though they can be held until the end of the imposed term, at the New Zealand Board’s discretion.

Short-term: The prisoner is sentenced to a custodial episode of fixed length, with the longest sentence chain (after taking into account cumulative and concurrent directives) being less than or equal to two years. Currently the law requires shorter-term sentenced prisoners to be released after serving exactly half of the imposed sentence

Other custody: Is a catch-all category designed to ensure that any anomalous data indicating a custodial sentence is not lost.

Remanded in custody

An individual may be remanded in custody by the court and held in police cells, court cells, psychiatric facilities or corrections facilities. The remand period is normally short and specific or until a specified court day for trial or for sentencing. It is very common for remand prisoners to have multiple charges on each remand warrant, with new and successive remand warrants issued during the course of a single episode on remand. Remand warrant data is available for analysis only from mid-1998 onwards.

Extended supervision orderOffenders may be subject to an order, imposed by the court and with conditions set by the New Zealand Parole Board, by which they are managed by the Community Probation Services. The order can apply for up to 10 years following a finite term of imprisonment. High and long-term risks posed by some sex offenders in the community are the primary target of this order. This was introduced in 2004.
Released to HD

Home detention is an electronically monitored and supervised restriction to live and stay at a specified address. Home detention is managed by Community Probation Services.

Up until October 2007 home detention was ordered by the New Zealand Parole Board and there were two conceptually different types of such orders. Back-end home detention was ordered to manage an offender’s return to the community after a long-term prison sentence. Front end home detention was ordered as a means of serving a short-term prison sentence, if the sentencing judge had granted leave for an application to be made to the New Zealand Parole Board.

Since 2007 the New Zealand Parole Board has been able to order Parole with full residential conditions.

Home detention sentenced

In October 2007 the new sentence of Home Detention was introduced. In implementation home detention sentences are almost identical to the home detention orders (described above) but  are sentences of the Court rather than orders of the New Zealand Parole Board.

Community detention

In October 2007 the new sentence of Community Detention was introduced. This is conceptually an electronically monitored curfew.


Prison sentenced prisoners may be ordered to be released to parole management by the New Zealand Parole Board. Parole requires that the offender meets regularly, and works closely with a probation officer, who ensures that special conditions imposed by the Board are fulfilled.

Released with conditions

Prison sentenced prisoners may have post release conditions imposed by the court at the time of sentencing. Such conditions are overseen by a probation officer.

Intensive supervision

In October 2007 the new sentence of Intensive Supervision was introduced. This sentence is similar to supervision described below but involves a higher level of restriction and has a longer maximum term (24 months), and special conditions that may include residential programmes.


Offenders sentenced to supervision report regularly to a probation officer and, if ordered by the court, fulfil special conditions designed to address their risk of further offending.

Supervision may include in-depth,focused interventions such as non-residential rehabilitative programmes, reintegration services, or counselling that addresses their offending. In October 2007, the maximum duration of supervision was cut from 24 to 12 months.

Post detention conditionsAfter completion of home detention, offenders may be directed to abide by a set of conditions for a period.
Community workOffenders sentenced to community work complete a prescribed number of hours of work within the community. Community work sentences came into effect with the Sentencing Act 2002, and provide for a degree of reparation to the community.
Other communityThis covers all predecessors of community work including community service and periodic detention sentences.
Paused managementRefers to offenders who were under management but are temporarily released for some reason, such as suspended sentence, or bail, or legally recallable but with no parole order.
DeportedThese individuals are known to have been deported.
Not managedThese individuals are not currently managed by the Department of Corrections.

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12.3 Gender

The Department of Corrections’ databases record four gender types: Men, Women, Unknown and Indeterminate. In most of the figures in this report, the Unknown and Indeterminate gender groups have been counted in the Men gender group. This amalgamation is so small that there is minimal effect on the overall numbers.

12.4 Age

Age data in this collection is generally calculated from the recorded date of birth until the date of interest. Where this calculation has resulted in anomalous results, such as negative numbers, or less than fifteen years old,the offender is grouped with those of an Unknown age.

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12.5 Ethnicity
12.5.1. Preferred ethnicity

In determining preferred ethnicity, individuals are associated only with their most recent self-identified preferred ethnicity, as recorded in the Department of Corrections’ database and grouped according to Statistics New Zealand ethnicity groupings (see ethnicity groupings here).

Where no ethnicity is available from the Department’s records, historical information is sourced from the Ministry of Justice data warehouse. The data warehouse inherited ethnicity data from the Law Enforcement System (LES), which was based on police officers’ assessments of the offender’s ethnicity.

The majority of the data (and all of it since 1998) comes from the Department’s database. Even with the inclusion of the supplementary data, there are significant numbers of individuals with unknown ethnicity prior to 1998.

The preferred ethnicity approach used follows Statistical Standard for Ethnicity 2005, but differs in a couple of ways:

  1. it does not multiple-count individuals who have identified with multiple ethnic groups, instead placing them in their preferred ethnic group
  2. it has not collected the ethnicity data in the way prescribed in the 2005 standard. Instead, the ethnicity data results from an amalgam of historical methodologies relating to the agency doing the collecting, and the standard of the day.
12.5.2. Multiple ethnicity

The Department of Corrections asks for ethnicity information at each reception and offenders are associated with all their most recently selfidentified ethnicities. This information is recorded in the Department of Corrections’ database and grouped according to the Statistics New Zealand ethnicity mapping. This means that it is possible for an individual to be counted in multiple ethnic groups at one time. Note that this differs from the preferred ethnicity approach described above, where individuals are only associated with a single ethnic group.

The multiple ethnicity approach is only used in this report for figures showing snapshots of age, gender and ethnicity groupings which are compared against national population data. This provides a best match in methods for comparing the two data sets. However, an exact match with the methods prescribed in the Statistical Standard for Ethnicity 2005 has not been possible, as the Department’s ethnicity data results from an amalgam of historical methods relating to the time the data was collected, the agency doing the collecting and the standard of the day.

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12.6 Offence prioritisation

Two methodologies for prioritising offences are utilised in this report: most serious offence (as charged) is used for remand periods; and lead offence is used for sentenced periods.

Term UsedMeaning an episode of management where:
Most serious offence (as charged)

This is similar to a method commonly used by the Ministry of Justice. For each episode of remand only offences relating to that episode are considered. The most serious charge is selected according to the Ministry of Justice seriousness score, which is described below:

"A seriousness of offence scale was originally developed by the Policy and Research Division of the Department of Justice in 1991, and has been updated about every five years since then. The most recent update of the scale occurred in February 2005 by the Ministry of Justice. The updated scale gives imprisonable offences a score according to how serious judges have deemed each offence in terms of the use of custodial sentences over a specific time period.

The updated scale is based on court sentencing data for the period 2000 to 2004. The seriousness score assigned to each offence is the average number of days of imprisonment imposed on every offender convicted of that offence between 2000 and 2004, where the average
is taken over both imprisoned and non-imprisoned offenders. Suppose, for example, that between 2000 and 2004 there were 100 cases of offenders convicted of a particular offence. Of these cases, 50 resulted in a custodial sentence, and the average length of the custodial sentences imposed on these offenders was 30 days. The seriousness score for this offence is (30 x 50/100), or 15.

Offences that became obsolete prior to 2000 were given the same score as any new similar offences, or a score was calculated based on sentencing data before 2000. Imprisonable offences for which there were convictions but no custodial sentences over the period 2000 to 2004, were given a seriousness rating slightly lower than the least of the offences already assigned a seriousness score (i.e. a score of 0.2). Non-imprisonable offences were assigned a seriousness score of zero."

 Lead offence

For sentences, the lead offence is the offence that has the longest sentence duration imposed.

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12.7 Offence grouping

The table below provides descriptions of the offence groups used in this report. The offence groups are based on the Australia New Zealand Standard Offence Classification (ANZSOC) offence divisions. A full description of the ANZSOC classification methodology may be found at: http://archive.stats.govt.nz/

Report offence groups (ANZSOC offence groups)*Offence examples
Homicide (01)*

Attempted murder
Driving causing death

Assault (02)*

Common assault
Serious assault causing injury

Sexual assault (03)*

Aggravated/non-aggravated sexual assault
Non-assaultive sexual offences against a child
Child pornography offences

Robbery, extortion (06)*

Robbery/aggravated robbery

Other acts threatening persons (04,05)*

Endangering others
Abduction/kidnapping/false imprisonment
Neglect/ill-treatment of person in care
Dangerous driving

Burglary, theft, fraud (07,08,09)*

Unlawful entry with intent/burglary, break and enter
Theft of a motor vehicle
Receiving or handling proceeds of crime
Obtaining benefit by deception

Illicit drug offences (10)*

Import illicit drugs
Manufacture or cultivate illicit drugs
Sell/deal in illicit drugs
Possess/use illicit drugs

Good order (11,12,13,14,15,16)*

Disorderly/offensive behaviour, language, conduct
Property damage, arson
Weapons offences
Inciting hatred, Cruelty to animals
Liquor, tobacco, gambling offences
Traffic offences: excessive speed, driving while
intoxicated, driving while disqualified/without licence
Offences against justice: breach of bail/community
Subvert course of justice

 * The numbers in brackets refer to the Australia New Zealand Standard Offence Code
groupings as described at http://www.stats.govt.nz/

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12.8 Data mart

This report is based on the Offender Volumes data mart. It provides a single unambiguous timeline for each offender’s career. The new data-set enforces a one-day/one-status requirement for each offender. This is a huge simplification compared to the complexity of the data and overlapping directives in the lives of some of the offenders. However, it provides the basis for useful big picture analysis where the numbers are selfconsistent and data issues can be identified.

To achieve the one-day/one-status requirement, a trumping process has been introduced. The process provides the major management category in situations where the data indicates several things are happening simultaneously. It must be recognised that this means that exact alignment with many other Departmental reports is difficult. For example, under the trumping process, a supervision sentence takes precedence over a contemporaneous community work sentence, and a remand warrant takes precedence over a community sentence. In the timeline created, the unmanaged periods between sentences and orders are also available for analysis.

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12.9 Concept diagram of directives issued

Concept diagram of directives issued

The diagram above represents all the different sentence and order directives recorded for a single offender. This representation demonstrates how a number of records can overlap in time.

The Major Track and Major Management Track combine the sentences and orders into one, using a priority order.

The priority order for each track is as follows:

  • Prison sentenced
  • Remanded in custody
  • Extended Supervision Order
  • Home Detention sentenced
  • Community Detention
  • Paroled
  • Post Detention Conditions
  • Released on Conditions
  • Intensive Supervision
  • Supervision
  • Community Work
  • Other community
  • Paused management
  • Deceased
  • Deported
  • Desisted 10 years
  • Not managed

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