NSW Mandatory Alcohol Interlock Program

Since 1 February 2015 drivers who are convicted of high range, repeat or other serious drink driving offences in New South Wales will automatically be subject to the Alcohol Interlock Program. Prior to 1 February 2015 this program was voluntary.

What is an Interlock device?

Interlocks are electronic breath testing devices linked to the ignition system of your car, motorcycle or truck. Once the device is fitted in order to start your vehicle you need to breathe into the interlock device. Your breath is then analysed for the presence of alcohol. If alcohol is detected you will not be able to start your vehicle. If alcohol is not detected you will be able to start driving, however, randomly timed breath tests will occur when you are driving and you must also pass these tests to continue driving.


In NSW all Alcohol Interlock Program participants must have a zero blood alcohol concentration when driving.

The Interlock device records all the breath test results, takes a photograph of the person providing the sample and records any attempts made to tamper with the device.
If you are convicted of a mandatory interlock offence as defined in Section 209 of the Road Transport Act 2013 an Interlock Order will be issued by the Court. If you fail to comply with this order you will be disqualified from holding a licence for a period of five years from the date of your conviction.

If you are issued a mandatory Interlock Order you will also be disqualified from driving for a period of time (which is nominated by the Court). During this time you will need to have an interlock device fitted in your vehicle by an accredited interlock service. Once the disqualification period ends and the device has been fitted in the vehicle the period of the Interlock Order begins.

A mandatory Interlock Order is made in addition to any other penalty imposed by the court for the offence you have been charged with. An Interlock Order is made in addition to any other penalties, such as imprisonment and fines, you may receive for the offence you have committed.

The period of the Interlock Order varies according to the severity of the drink driving offence. The combined disqualification and minimum interlock periods are at least as long as the automatic disqualification period that applies for each offence under Section 205 of the Road Transport Act 2013.

Minimum interlock periods range from 12 months for low range drink driving offences to 48 months for high range drink driving and repeat drink driving offenders.

If you do not start or complete your Interlock Order you will remain disqualified from driving for at least five years from the date of your conviction.

Can you avoid a mandatory interlock order?

In some cases it is possible for the Court to make an Interlock Exemption Order. An Exemption Order can be made under section 212(3) of the Road Transport Act 2013, if the offender proves to the court’s satisfaction that they:

  • Do not have access to a vehicle in which to install the interlock device
  • Have a medical condition diagnosed by a registered GP that prevents them from being able to provide an adequate breath sample and the device cannot be modified to accommodate the medical condition

If you have been charged with a high range drink driving offence or you are a repeat offender the mandatory Alcohol Interlock Program will apply to you.

For advice on how this new mandatory program applies to your particular circumstances contact William Vahl of North Shore Criminal Law on 9955 2298 or 0400 44 64 24. William Vahl is an Accredited Criminal Law Specialist with over 20 years of experience representing people in court who have been charged with drink driving offences.