COVID-19 response

If you are looking for the latest legal information relating current Coronavirus laws in New Zealand, check out our new section: Coronavirus and the Law.

Communtity Law Manual | Driving & traffic law | Tests for alcohol or drug use

Drink/drug driving

Tests for alcohol or drug use

Land Transport Act 1998, ss 68–74

There are a range of tests the police can use to establish, or help establish, that you’ve broken the drink/drug driving laws:

  • Alcohol breath tests – There are three different types of breath test, which get progressively more accurate: a passive breath test (“sniffer” test), a breath screening test, and an evidential breath test.
  • Blood tests for alcohol or drugs – Blood tests can be used as the next step when you’ve failed an evidential breath test or refused to have one, or to establish whether you’ve taken drugs.
  • “Compulsory impairment tests” for drugs – Here the police test your functioning by, for example, asking you to stand on one leg. A conviction for driving while impaired by drugs requires both a failed impairment test and a blood test showing illegal drugs or prescription medicines.

Passive breath tests (“sniffer” tests)

Land Transport Act 1998, s 68(4)

If you’re driving (or trying to drive) and the police stop you, they can ask you to have a passive breath test. Here you speak into an electronic device, or “sniffer”, which detects whether there’s any alcohol on your breath at all. The sniffer can’t detect how much alcohol you’ve had.

If the sniffer does detect alcohol, or if you refuse to have the test, the police can ask you to have a breath screening test (see below). It’s not an offence to refuse a passive breath test.

Breath screening tests

Here you breathe into an electronic device that detects how much alcohol you have on your breath. However, these tests aren’t accurate enough themselves to be used as evidence in court.

When can I be asked to have a breath screening test?

Land Transport Act 1998, s 68

The police can ask you to have a breath screening test if:

  • they stop you when you’re driving or trying to drive (for example, at a police alcohol checkpoint), or
  • they have good reason to suspect you’ve recently committed a driving offence, or
  • you were involved in an accident as a driver (or if the police can’t establish who was driving the vehicle but they have a reasonable suspicion that you were in it at the time).

Can I refuse a breath screening test?

Land Transport Act 1998, s 59(1)(a)

Yes, you can. It’s not an offence to refuse a breath screening test. However, it is an offence if you have the test but then refuse to wait for the result. The police can arrest you for this, and if you’re convicted in court you can be fined up to $4,500. You can also be disqualified from driving for a period decided by the judge.

What happens if I fail a breath screening test?

Land Transport Act 1998, s 69

If the breath screening test shows you’re over the alcohol limit that applies to you, or if you refuse to take the test, the police will require you to go with them to have an evidential breath test (see below).

At this point, although you’re not under arrest, you’re being held (or “detained”) by the police, and therefore you have the right to talk to a lawyer and the right to refuse to say anything to the police. The police also have to tell you that you have these rights.

New Zealand Bill of Rights Act 1990, s 23(1)(b), (4)

Note: The police have a list of lawyers, under the Police Detention Legal Assistance scheme, who are available to give free advice to anyone who’s being detained by the police. You can contact them any time of the day or night. (See “Other legal assistance in criminal cases” in the chapter “Legal aid”.)

Evidential breath tests

An evidential breath test can be used as evidence against you in court if you’re charged with a drink-driving offence. These tests are more accurate than breath screening tests, which can’t be used in court.

You’ll be given the test either at a police station or in a police testing vehicle (“booze bus”).

When will I be asked to have an evidential breath test?

Land Transport Act 1998, s 69

A police officer can require you to go with them to have an evidential breath test if:

  • you’ve had a breath screening test and it shows you’re over the breath-alcohol limit that applies to you, or
  • you’ve refused to have a breath screening test, or
  • a breath screening test isn’t available and there’s good reason to suspect you’ve been drinking.

Can I refuse an evidential breath test?

Land Transport Act 1998, s 5(1)(b)-(d)

It’s not an offence to refuse to have the test itself, but it is an offence if you don’t go with the police officer to the testing place, or if you don’t stay there once you’ve arrived, or if you have the test but then don’t stay until the result is known. In these cases, the police officer can arrest you, and if you’re convicted in court you can be fined up to $4,500 and disqualified from driving for a period decided by the judge.

Also, if you refuse and a subsequent blood test shows your blood-alcohol level was between 50 and 80 milligrams (that is, the band for which adults can be given an on-the-spot infringement notice), you’ll have to pay a $700 infringement fee. This is much higher than you would’ve had to pay if you’d agreed to have the evidential breath test and then that test (or a subsequent blood test) showed you were within that infringement-notice band for breath-alcohol or blood-alcohol; in those cases the fine is only $200.

What are my rights if I fail an evidential breath test?

Land Transport Act 1998, s 56(2B); Land Transport (Offences and Penalties) Regulations 1999, Schedule 1

If you have an evidential breath test and it shows you’re over the limit that applies to you, the police officer must tell you this result and warn you that this could of itself lead to a court conviction or an infringement notice. If they don’t tell you this, the test result can’t be used in court or as the basis for an infringement notice.

Land Transport Act 1998, ss 70A, 77(3)-(3B)

After the police have told you this, you then have 10 minutes in which you can choose to have a blood test. In court, a blood test will override the results of the breath test.

However, the police don’t have to tell you that information, and you don’t have the right to choose a blood test, if you’re an adult on a standard driver’s licence and the evidential breath test shows you’re within the infringement-notice band of 250 to 400 micrograms, rather than the higher band (over 400 mcg) for which you can get a criminal conviction and a heavier penalty.

Blood tests for alcohol or drugs

When can I be required to have a blood test?

Land Transport Act 1998, ss 70A, 72

The police can require you to have a blood test:

  • if you’ve refused to have an evidential breath test
  • once you’ve chosen to have a blood test after an evidential breath test has shown you’re over the breath-alcohol limit that applies to you (see above, “Evidential breath tests”)
  • if an evidential breath test isn’t available
  • if you’ve been arrested on suspicion of a drink/drug driving offence and either a doctor believes you may be under the influence of drink or drugs or you’ve refused to let a doctor examine you
  • if you’ve failed a drug impairment test (see below, “Drug impairment tests”).

You have the right to choose to have a blood test if an evidential breath test shows you’re over the breath-alcohol limit that applies to you.

Land Transport Act 1998, ss 68(2), 69(7), 72, 73

A blood test must be taken by a doctor or nurse. If you’re in hospital after a traffic accident, breath tests aren’t permitted, but blood samples can be taken from you whether you agree to this or not, including while you’re unconscious.

Land Transport Act 1998, s 74(5)-(7)

Later you can ask for an independent analysis of the blood sample.

Can I refuse a blood test?

Land Transport Act 1998, s 60

No. If you refuse to have the blood test it’s a criminal offence. For a first or second conviction, you can be jailed for up to three months or fined up to $4,500, and you must be disqualified for at least six months.

Drug impairment tests

Land Transport Act 1998, ss 57A, 71A, 72(1)(e)

Drug impairment tests (“compulsory impairments tests”) are done by the police to find out whether your functioning has been affected by drugs or prescription medicines. A police officer will check whether your eyes are functioning normally, including for example how they react to light, and they’ll also ask you to walk and turn, and to stand on one leg.

If you fail the impairment test, or if you refuse to do it, the police can require you to have a blood test. If the blood test shows you’ve had illegal drugs or prescription medicines, you can be convicted of driving while impaired by drugs.

When can I be required to have a drug impairment test?

Land Transport Act 1998, s 71A

If the police have good reason to suspect you’ve taken drugs, they can require you to do an impairment test in any of the following situations:

  • if they stop you while you’re driving or trying to drive (for example, at a police alcohol checkpoint)
  • if they have good reason to suspect you’ve recently committed a driving offence
  • if you were involved in an accident as a driver (or if the police can’t establish who was driving the vehicle but they have a reasonable suspicion that you were in it at the time).

Can I refuse to have a drug impairment test?

Land Transport Act 1998, s 60(1)(d)

No – it’s an offence to refuse to have a drug impairment test. For a first or second conviction, you can be jailed for up to three months or fined up to $4,500, and you must be disqualified for at least six months.

back to top
Page Reader Press Enter to Read Page Content Out LoudPress Enter to Pause or Restart Reading Page Content Out LoudPress Enter to Stop Reading Page Content Out LoudScreen Reader Support