‘Mostly at fault’ is defined in the Motor Accident Injuries Act 2017 (MAIA) to be “greater than 61%” contributory negligence.
Where an injured person is ‘mostly at fault’, their statutory benefits cease after 26 weeks, but even if an injured person is not mostly at fault, their weekly payments may be reduced after 26 weeks by the extent of their contributory negligence.
The assessment of contributory negligence is always difficult because multiple variables are at play and no two cases are exactly the same. It is impossible to define, with precision, when contributory negligence will be assessed over 61%.
Based on the contributory negligence case summaries, however, these guidelines may assist in assessing whether it is likely that the injured person’s contributory negligence exceeds 61%.
Section 3.39 of the Motor Accident Injuries Act 2017 (MAIA) mandates that the Mental Harm provisions in Part 3 of the Civil Liability Act 2002 (CLA) apply to the payment of statutory benefits under MAIA in the same way they would apply to an award of damages, “subject to any necessary modifications and to any modifications prescribed by the regulations”.
Clause 8 of the Regulations specifically modifies s 30(3) of the CLA to work in the statutory benefits arena. Otherwise, stakeholders are required to use their own judgment in deciding how the provisions in Part 3 of the CLA should be “necessarily modified” to apply to statutory benefits claims.
These Guidelines represent an attempt to apply “necessary modifications” to Part 3 of the CLA so that they apply to claims for statutory benefits. Pending guidance from the Courts or the Dispute Resolution Service, they are Guidelines only and do not represent decided law.
The Supreme Court clarified in AAI Limited v Singh  NSWSC 1300 that s 3.2(5) of the Motor Accident Injuries Act 2019 deems the Relevant Insurer liable to pay Statutory Benefits but does not deem the owner or driver to be at fault.
Furthermore, in strong obiter remarks, the Supreme Court in Singh held that the deeming provisions in Part 5 of the Act, relevant to ‘no-fault accidents’, can not be used to deem a driver “wholly or mostly at fault” in the Statutory Benefits arena.
These Guidelines set out the practical impact of Singh in Statutory Benefit claims arising from single-vehicle accidents, multi-vehicle accidents and pedestrian accidents.