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What Is the “Legal Limit” For Driving in Western Australia?

The blood alcohol content that triggers a drink driving offence depends upon several factors

Drivers commit an offence if they drive while under the influence of alcohol, but it is not necessary to be drunk or impaired by alcohol to be charged with a drink driving offence. Driving with a blood alcohol content (BAC) that exceeds a specified limit is also an offence. Since that offence can have serious consequences, you should talk to a lawyer if you are accused of driving while you are “over the limit.”

What is BAC?

You blood alcohol content is a measurement of the number of grams of alcohol in 100 mL of your blood. It can be accurately measured by a blood test. It is more commonly measured by a breath test using a device that samples deep lung air and uses a formula to convert alcohol detected in your breath to alcohol in your blood. Since that formula depends upon assumptions that are not necessarily true in every case, a breath test is less accurate than a blood test.

What is the Legal Limit?

It is an offence in Western Australia to drive if your BAC is 0.05 or higher. That limit applies to adult drivers who hold a full licence and are driving ordinary vehicles for their own transportation.

What is the Legal Limit for Novice Drivers?

A driver who has held a licence for less than two years cannot legally drive with a BAC above zero. A P-plate driver who has been licenced for more than two years is subject to the same 0.05 limit as other drivers.

Who Else is Subject to a BAC limit of Zero?

Drivers cannot legally drive with a BAC above zero when:

Driving a vehicle while carrying any passengers if the vehicle is designed to carry at least 11 passengers;

Driving an omnibus while carrying passengers for hire;

  • Driving a taxi while carrying passengers;
  • Driving a vehicle that has a gross weight exceeding 22.5 tonnes;
  • Driving any vehicle if you have a prior conviction for DUI or 2 prior convictions for driving in excess of 0.08 and your licence disqualification ended within the past 3 years.

 How Does a BAC Affect Drink Driving Penalties?

If you are subject to a BAC limit of zero, you face a more serious penalty if your BAC is 0.02 or higher. If it is 0.05 or higher, you will be charged with the same drink driving offence that applies to all drivers. That offence also carries more severe penalties.

As BAC levels increase, so do penalties. The highest penalties generally apply to drivers who have a BAC of 0.15 or higher. You should talk to a lawyer whenever you are accused of driving with a prohibited BAC.

Disclaimer : This article is just a summary of the subject matter being discussed and should not be regarded as a comprehensive legal advice for you to defend yourself alone. If you are charged with criminal offences, it is recommended that you seek legal assistance from criminal lawyers.


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