What is an interlock?

It is an electronic breath testing device which are installed and linked to your motor vehicle, motorcycles, and heavy vehicle ignition.

Prior to starting the ignition, you would be required to provide a breath sample into the device for the presence of alcohol. If alcohol is detective in your breath analyses, your vehicle will not start.

Randomly times breath tests must also be passed during a journey. The interlock device includes a camera and takes a photograph of the person providing the breath sample to reduce the risk of a driver using someone else’s breath sample to start the vehicle.

Who does Alcohol Interlock Program apply to?

All drivers convicted of high-range drink driving, middle range drink driving, driving a motor vehicle under the influence of alcohol offences committed repeat and other serious drink-driving offences.

Offenders are ordered by the court to complete:

  • A minimum licence disqualification period, and
  • A period of participation in the interlock program (at least 12 months).

The length of the minimum disqualification and interlock period depend on the offence type. Longer periods apply for the most serious offences.

The Court may grant an exemption from participating in the interlock program, but only in limited circumstances.

Interlock Offences, Disqualification Period and Interlock Periods

Mandatory interlock offenceDisqualification and interlock periods under interlock order
Disqualification period
Disqualification and interlock periods under interlock order
Minimum interlock period
Disqualification period
(if exemption order is made)
Note: as per Road Transport Act 2013 s 205
Applies to offences committed on or after
Low, novice or special range PCA – second or subsequent offenceMin: 1 month
Max: 3 months
12 monthsAutomatic: 12 months
(Min: 6 months)
1 Feb 2015
Mid range PCA – first offenceMin: 3 months
Max: 6 months
12 monthsAutomatic: 12 months
(Min: 6 months)
3 Dec 2018*
Mid range PCA – second or subsequent offenceMin: 6 months
Max: 9 months
24 monthsAutomatic: 3 years
(Min: 12 months)
1 Feb 2015
High range PCA – first offenceMin: 6 months
Max: 9 months
24 monthsAutomatic: 3 years
(Min: 12 months)
1 Feb 2015
High range PCA – second or subsequent offenceMin: 9 months
Max: 12 months
48 monthsAutomatic: 5 years
(Min: 2 years)
1 Feb 2015
Drive under the influence of alcohol – first offenceMin: 6 months
Max: 9 months
24 monthsAutomatic: 3 years
(Min: 12 months)
3 Dec 2018
Drive under the influence of alcohol – second or subsequent offenceMin: 9 months
Max: 12 months
48 monthsAutomatic: 5 years
(Min. 2 years)
3 Dec 2018 *
Refuse to provide a sample – first offenceMin: 6 months
Max: 9 months
24 monthsAutomatic: 3 years
(Min: 12 months)
1 Feb 2015
Refuse to provide a sample – second or subsequent offenceMin: 9 months
Max: 12 months
48 monthsAutomatic: 5 years
(Min: 2 years)
1 Feb 2015

Interlock exemption orders

A court may make an interlock exemption order only of the offender proves to the court’s satisfaction, that,

  • The offender does not have access to a vehicle in which to install an interlock device. For example- there is only one vehicle the offender has access in which an interlock device would be installed, and it is used jointly with a family member or other person who has a medical condition preventing then person from proving a sufficient breath sample to operate the device. Or,
  • The offender has a medical condition diagnosed by a registered medical practitioner that prevents the offender from providing a sufficient breath sample.
  • If the offender is convicted of middle range drink driving that is for a first offence and that making of the mandatory interlock order would cause severe hardship to the offender and the making of an interlock exemption order is more appropriate in all the circumstances than making the mandatory interlock


“access” to a vehicle means:

If the person is the registered owner, owner or part owner of the vehicle or shares the use of the vehicle with the registered operator, owner or part owner of the vehicle, and

It is reasonable in all the circumstances to install an interlock device the vehicle.

An interlock order must not be made (except in relation to a conviction for an offence against middle range drink driving, that is a first-time offending, merely because an offender

  • Cannot afford the cost of installing or maintaining the interlock device. However, financial assistance may be available in certain circumstances.
  • The offender will be prevented from driving a vehicle in the course of his or her employment if an interlock order is made, or
  • Has access to a vehicle but the registered operator of the vehicle refuses to consent to the installation of the device.

Costs

The offender must pay the installation and service of the device.

It is estimated that the standard costs to participants will include:

  • Interlock device installation
  • Monthly device leasing
  • Regular device servicing (monthly or bi monthly) and
  • Device removal at the end of the mandatory interlock period.

These standard costs are estimated to be about $2,200 a year.

If you attempt to drink drive, or to interfere with the interlock your device, this is recorded. Your device may require extra servicing or checks at additional cost to you.