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The cost of our convictions

This article was published 11 years ago. Content may no longer be relevant.

Every year there are two and a half thousand convictions of people aged 25 and under for possession and/or use of an illicit drug or drug utensil in New Zealand.

Between 2007 and 2011, there were 12,895 convictions in this age range. Over this period, New Zealand has spent more than $59 million imprisoning those who are convicted of minor drug offences and have to serve custodial sentences. This money is spent on imprisonment costs alone – it does not include costs to Police, the courts, treatment or probation.

With an average cost of over $18,000 per person imprisoned for minor drug offences, we have to start asking, what is the cost of convicting young New Zealanders?

The reality is that lots of New Zealanders will use drugs at some stage in their lives.

According to a Ministry of Health survey, about half of all adult New Zealanders – or around 1.4 million people – have used illegal drugs. Around 485,500 had done so in the past year.

Most people will use drugs when they are young. The Ministry of Health found that over half of those aged 18–24 and almost two-thirds of those aged 25–34 admitted to using illegal drugs.

Data from the Christchurch Health and Development Study found the rates of youth drug use to be even higher. By the age of 25, over 77 percent of the young people in their study admitted to using illegal drugs.

bar-chart. men used more than women except 16-17 age group. largest usage rate in 25-34 age group. least 55-64 - Ever used any drugs for recreational purposes in lifetime, among total population aged 16–64 years, by age group and gender (unadjusted prevalence).

Unsurprisingly, young New Zealanders are often the ones being caught up in the criminal justice system.

This is a bad thing for many reasons. It severely narrows opportunities: it’s harder to get a job, harder to travel, harder to get credit and harder to do many things most of us take for granted. It also exposes them to a negative environment, and it puts them in prison – a university of crime where drug use is rampant and joining a gang is often necessary for protection. All of this at a time when their brains and identities are forming.

We are stacking the odds against our young people. Almost half of all people convicted of possession and/or use of an illicit drug or drug utensil are aged between 17 and 25.

Number and percentage of 17–25-year-olds convicted of possession and/or use of an illicit drug or drug utensil
44% 45% 45% 44% 41%
4,456 2,662 3,020 2,702 2,055


Gender and ethnicity plays a role too. Significantly more males are convicted every year than females.
Female 351 363 394 366 277
Male 2,103 2,297 2,623 2,336 1,1778
Unknown 2 2 3 0 0
Total 2,456 2,662 3,020 2,702 2,055


Despite Māori making up 15 percent of the population, Māori aged 17–25 make up 37 percent of those convicted of possession and/or use of an illicit drug or drug utensil.
Pakeha 1259 1391 1605 1501 1112
Māori 965 990 1131 989 765
Other 80 73 94 69 68
Pacific 103 143 159 130 99
Unknown 49 65 31 13 11


Twelve percent of all people under 25 who are convicted are given a jail sentence.
Sentence type20072008200920102011
Imprisonment 13% 11% 11% 12% 12%
Community work 28% 28% 30% 30% 30%
Monetary penalty 37% 33% 31% 27% 25%


The average sentence that comes with a conviction is short but just long enough to mean loss of job, loss of flat or failure of study courses.
Age groupMean sentence (days)
Under 17 30
17-25 64


Also, there are discrepancies between the sentences for various drugs.
Drug typeClassMean sentence (days)
BZP C 425
Cannabis C 49
Cocaine A 60
Ecstasy B 131
Methamphetamine A 75
Heroin A 75

The mean sentence for possession of BZP is 425 days, while people who are in possession of heroin or methamphetamine get 75 days. This is obviously not a system based on relative harms.

All this is costing us.


Putting people in jail costs us. The Department of Corrections puts the cost of imprisoning one person at around $250 per day.
Age groupNumber of people sentencedMean sentence (days)Cost per personTotal cost
Under 17 3 30 $7,500 $22,500
17-25 1278 64 $16,000 $20,448,00


Per drug, the costs are even more astounding. These are the costs of those imprisoned between 2007–2011 for minor drug offences, broken down by drug type and sentence.
Drug typeNumber of people sentencedMean sentence (days)Cost per personTotal cost
BZP 2 425 $106,250 $212,500
Cannabis 1,050 49 $12,250 $12,862,500
Cocaine 4 60 $15,00 $60,000
Ecstacy 21 131 $32,750 $687,750
Methamphetamine 387 75 $18,750 $7,256,250
Heroin 11 75 $18,675 $205,425

That means we spend over $4 million a year imprisoning young people for minor drug offences. This is just the cost of imprisoning. It does not include Police costs, court costs, legal aid costs, probation costs or social costs.

The costs


to imprison one person for one day.


number of convictions for minor drug offences between 2007 and 2011.


spent between 2007 and 2011 imprisoning people for minor drug offences.


spent between 2007 and 2011 imprisoning people 25 and under for minor drug offences.


average number of days people are in prison for possession of BZP.


average number of days people are in prison for possession of cannabis.


average number of days people are in prison for possession of methamphetamine.


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