Police powers to arrest and detain

Police have powers to arrest and detain people to keep the peace, prevent crime and protect property.

This webpage will help you to understand more about these police powers.  Find out:

  • What are police powers?
  • When can police make an arrest?
  • What should the police do during an arrest?
  • What should I do if I’m being arrested?
  • Will I be taken into custody?

This Infosheet provides more detail about police powers to arrest and detain.

What things can the police do?

Police have the power to:

  • arrest and detain people
  • obtain certain information such as fingerprints and photographs
  • carry out searches
  • seize things
  • order you to leave a public place for up to 24 hours (called a move on notice)
  • issue Police Orders when investigating possible situations involving family violence.

They also have special powers in traffic matters, such as requiring you to provide a sample of your breath, or going with them to a police station to give a breath or blood sample.

When can police make an arrest?

Police can arrest you if they have an arrest warrant. An arrest warrant is written order from a justice of the peace, magistrate or judge that gives police the permission to arrest you. 

The police can also arrest you without an arrest warrant:

  • if they reasonably suspect that you have committed or are committing an offence that has imprisonment as a possible penalty
  • if you are doing, or they reasonably suspect you are about to do, something that involves violence or is likely to cause someone to fear that violence will be used
  • to prevent you committing a breach of the peace
  • if they reasonably suspect you have committed, are committing, or are about to commit:
    • an offence that has imprisonment for 5 years or more as a possible penalty
    • an offence of breaching an FRVO, VRO or Police Order, or
    • an offence that involves certain serious acts or threats of family violence.

The police can also arrest you if they reasonably suspect you have committed, are committing, or are about to commit any offence and also reasonably suspect that if they do not arrest you:

  • you are likely to continue or repeat the offence
  • you are likely to commit another offence
  • you are likely to endanger yourself or someone else's safety
  • you are likely to interfere with witnesses, evidence or the investigation, or
  • there is no other lawful way to find out who you are.

What should the police do during an arrest?

Tell you that you are under arrest. They might also place their hands on you or physically seize you, but they can only use as much force as is reasonably necessary.

Police must inform you of your right to:

  • medical treatment
  • privacy from mass media
  • an opportunity to tell a friend or relative where you are, and
  • an interpreter if required.

If you are arrested as a suspect they must inform you of your right to:

  • be told what you’ve been arrested for
  • an opportunity to speak with a lawyer
  • wait for an interpreter before police interview you
  • be cautioned before you are interviewed.

What should I do if I’m being arrested?

Be calm and polite. If you resist or struggle, or interfere with someone else being arrested, you could be charged with an offence.

Will I be taken into custody?

If you have been arrested as a suspect, police can keep you in custody for a reasonable time to:

You must be released if police decide not to charge you. If they do charge you, you might be released on summons or bail, if police think that is appropriate. If you are charged and not released, you will be kept in custody to appear before a court, where you can apply for bail.

 

Resources

 

Reviewed:  16 February 2022

Disclaimer

The information displayed on this page is provided for information purposes only and does not constitute legal advice. If you have a legal problem, you should see a lawyer. Legal Aid Western Australia aims to provide information that is accurate, however does not accept responsibility for any errors or omissions in the information provided on this page or incorporated into it by reference.