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DNA samples: When you have to give a sample

When you give a DNA sample voluntarily

When can the police ask me for a voluntary DNA sample?

Criminal Investigations (Bodily Samples) Act 1995, ss 6, 7

If the police have reasonable grounds to believe that a DNA sample would confirm or disprove that you were involved in a criminal offence for which you could jailed, they can ask you to give a DNA sample.

Steps the police have to take when they ask for a DNA sample

Criminal Investigations (Bodily Samples) Act 1995, ss 6, 7; Criminal Investigations (Bodily Samples) Act 1995, s 11

The police must give you information about your rights and about the processes for taking and analysing the sample. As well as giving you a written notice, they must also tell you certain key things, in a way and in language you can understand, including:

  • the offence their request relates to
  • that they have reasonable grounds to believe the sample will confirm or disprove whether you were involved in the offence
  • that you don’t have to give a sample, and if you do agree to giving it, you can withdraw your consent at any time before you give the sample
  • that you can talk to a lawyer before deciding whether to consent
  • that the sample can be used in evidence against you in court
  • that if you don’t consent, and there’s good reason to suspect you committed the offence, the police might apply to a District Court judge for a compulsion order requiring you to give the sample.

Note: You have 48 hours to decide whether to agree to giving a sample. After that, the law treats you as having refused consent.

Criminal Investigations (Bodily Samples) Act 1995, s 9; Criminal Investigations (Bodily Samples) Act 1995, s 10

To be legally valid, any consent (agreement) you give for a DNA sample has to be:

  • in writing and signed by you, or
  • given verbally and recorded on video.

The same applies to any consent given by your parents if you’re under 18.

Note: At any stage before you give a DNA sample, you can change your mind and withdraw your consent.

Special requirements for police requests for DNA samples from young people

Criminal Investigations (Bodily Samples) Act 1995, s 8; Criminal Investigations (Bodily Samples) Act 1995, ss 8, 24, 49A, 52A

If you’re aged 14, 15, 16 or 17, and the police want to ask you for a DNA sample, the conditions explained above still apply, but with these extra requirements for your parents to be involved:

  • Notifying your parents – The police have to take all reasonable steps to also give one of your parents a copy of the required written notice that you’ve been given.
  • Parent’s consent also needed – At your age a sample can only be taken from you if both you and one of your parents agree to it. The police have to tell you this, and also that your parents don’t have to agree. The written notice given to you and your parent must also say that if your parent does agree to you giving the sample, they can withdraw this consent at any time before the sample is taken. The notice must also say that your parents may want to talk a lawyer before deciding whether to consent. If the police don’t get consent from both you and a parent, then the only way they will be able to get a DNA sample from you is through applying to a judge for a compulsion order.
  • Parents can be present for the sample – The police must also tell your parent that you can have one of your parents present when you give the sample.

If you’re under 18 and you choose to give a mouthswab (“buccal”) sample yourself, an independent adult must be present and you have to first confirm in the presence of that adult that you’ve chosen to give the sample yourself. An “independent adult” can be one of your parents, a lawyer, or another person chosen by your parents; if none of those people are available, it can be any adult you choose (but not a police officer).

Note: The police can’t ask for samples from children under 14. However, when the suspected criminal offence is one of those more serious offences for which the child could be legally be prosecuted at their particular age (see www.youthlaw.co.nz for more information), the police can apply to a judge for a juvenile compulsion order to obtain a DNA sample.

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