By James Stevens, Director and Solicitor, Go To Court Lawyers. Last reviewed 10 April 2026.
The Heavy Vehicle National Law (HVNL) and Regulations commenced in South Australia in February 2014 and it now applies in the majority of states and territories. It replaced the existing state and territory laws with a single heavy vehicle national rulebook. It set up the National Heavy Vehicle Regulator (NHVR) to oversee the law. With some exceptions, a vehicle is a heavy vehicle if it has a GVM (gross vehicle mass) or ATM (aggregate trailer mass) of over 4.5 tonnes. These laws apply to every person in the chain of responsibility for the vehicle. A person who is charged with heavy vehicle traffic offences in South Australia as a result of being in the chain of responsibility may be able to rely on a reasonable steps defence. Any vehicle, or any combination of vehicles, or a bus with a GVM over 8 tonnes which has 3 or more axles is a fatigue regulated heavy vehicle (with some exceptions). The drivers of these vehicles must comply with the driver fatigue laws. The laws fall within the chain of responsibility regime and people other than the driver may be charged with an offence. Everyone in the chain of responsibility must take all reasonable steps to help make sure that a person does not drive when they are fatigued. An individual’s obligations will depend on their role in the chain. It is possible to be guilty of an offence even if no one ultimately drove while fatigued. The work and rest hour offences are divided into 4 categories – minor, substantial, major and critical risk. These offences all carry heavy fines and major risk and critical risk breaches also carry demerit points. The categories are calculated on the minutes that a person works on top of their allowable work or rest hours. Unless they have an exemption all drivers must record their work and rest hours in a work diary if they drive 100 km or more from their home base or work under basic fatigue management or advanced fatigue management. If a driver is charged with a work/rest offence, they may be able to defend the charge if they can prove that they did take enough breaks, or that they did not either feel or act fatigued, or if they show another reason that explains their manner of driving. A person in the chain of responsibility charged with one of these offences may be able to use the reasonable steps defence Under the HVNL, proper records must be kept for drivers of a fatigue regulated heavy vehicle. Responsibility for keeping records may be with the employer, accredited operator, or the driver, depending on the driver’s employment status. The records must be kept for three years and must be available for inspection when required. If a heavy vehicle is overloaded, the penalty is calculated on the percentage that the load is over the allowable weight and takes into consideration whether the person charged is an individual or body corporate; and whether this is a first or a repeat offence.- A minor risk breach is breach up to 5% above the allowable weight.
- A substantial risk breach is breach between 5% and 20% above the allowable weight.
- A severe risk breach is one that is above 20% over the allowable weight. The penalty will increase with each percent that the load is over 20% of the allowable weight.
- Formal warnings – these can be given if the person charged took all reasonable steps to prevent a breach of the law and they were not aware that a law had been breached. A warning can't be given if the charge is for a substantial or severe risk breach of a mass, dimension or loading requirement. A warning may be withdrawn within 21 days and further legal action taken for the offence.
- An infringement notice can be issued imposing a fine and/or demerit points.
- Court orders – the court has the power to impose fines, demerit points, compensation orders, commercial benefits penalty orders, prohibition orders, cancellation/suspension of vehicle registration and supervisory intervention orders.
Frequently Asked Questions
What is the reasonable steps defence for heavy vehicle chain of responsibility offences?
The reasonable steps defence allows people in the chain of responsibility to avoid liability by proving they took all reasonable steps to prevent the offence. This defence recognises that not everyone in the chain has direct control over the vehicle operation. The steps required depend on your specific role and the circumstances. Documentation of safety procedures, training records, and compliance systems can support this defence when facing heavy vehicle charges.
How does South Australia enforce the Heavy Vehicle National Law differently from other states?
South Australia adopted the Heavy Vehicle National Law in February 2014, creating uniform enforcement with most other states through the National Heavy Vehicle Regulator. However, SA Police and authorised officers conduct local enforcement activities within the state. Some exemptions and permits may have state-specific conditions. The penalties and court processes follow South Australian procedures, meaning local legal representation familiar with SA courts is essential for heavy vehicle matters.
What are the costs involved in defending heavy vehicle traffic charges in South Australia?
Heavy vehicle offence penalties can include substantial fines, licence suspensions, and impact on operating authorities. Go To Court Lawyers offers a fixed-fee consultation to assess your case and explain potential defences like reasonable steps. Legal representation costs vary depending on case complexity, but early legal advice often saves money by avoiding convictions that could affect your livelihood or business operations in the transport industry.
How can a traffic lawyer help with heavy vehicle chain of responsibility charges?
A traffic lawyer can examine whether you were actually in the chain of responsibility and assess available defences like reasonable steps. They can gather evidence of your compliance systems, negotiate with prosecutors, and represent you in court. Lawyers can also advise on minimising penalties, protecting your licence, and ensuring charges don't affect other family members or employees who may also face prosecution under the chain of responsibility provisions.
What are the time limits for responding to heavy vehicle traffic charges in South Australia?
Heavy vehicle charges require immediate attention as court dates are typically set within weeks of the charge. You must enter a plea by the specified court date or risk additional penalties. Evidence gathering for reasonable steps defences takes time, so early legal advice is crucial. Delay can limit defence options and increase penalties. Contact a lawyer immediately after receiving charges to preserve all available defences and ensure proper court preparation.
Related Traffic Law topics in SA
Appealing Traffic Fines in South Australia - Review Process and Court OptionsCareless Driving and Dangerous Driving (SA)Caught by a Red Light Camera in South Australia - Challenge Your FineCaught Using Your Mobile Phone While Driving in South Australia - What Happens Now?Charged With Dangerous Driving in South Australia - What Happens Now?Charged With Driving While Suspended or Disqualified in South Australia - What Happens Now?Charged With Heavy Vehicle Offences in South Australia - What Happens Now?Charged With Hoon Driving or Street Racing in South Australia - What Happens Now?Charges Following a Car Accident in South AustraliaCyclists in South Australia - The RulesDriving Unlicensed in South AustraliaDriving Unregistered (SA)Driving Whilst Suspended in South AustraliaFacing Licence Suspension for Demerit Points in South Australia - Your Rights and OptionsFailing To Stop For Police In South AustraliaHeavy Vehicle Traffic Offences in South AustraliaHoon Laws in South AustraliaLicence Disqualifications (SA)Police Vehicle Searches in South AustraliaReceived a Seatbelt Fine in South Australia - Challenge Your PenaltyReceived a Speeding Fine in South Australia - How to Challenge Your InfringementRestricted Licences in South AustraliaSerious Traffic Offences in South AustraliaSpeed Camera Fine in South Australia - Challenge It or Pay
See all Traffic Law topics in SA →