The NSW Motor Accidents Authority (MAA) will launch new claims assessment guidelines for compulsory third party (CTP) insurers on Thursday.

The guidelines apply to applications to the authority’s Claims Assessment and Resolution Service (CARS) on or after launch day, plus matters that have yet to be determined.

The grounds for claims exemptions have changed, in line with a ruling last September by the NSW Supreme Court involving Allianz.

The insurer denied liability for its client after a motor accident in 2005, prompting a court appeal by the other driver involved in the crash, Michael Smalley, after three decisions against him by CARS.

The NSW Court of Appeal ordered the three decisions quashed because they relied on “an incorrect view of the law”. The matter was referred back to CARS and Allianz was ordered to pay Mr Smalley’s costs.

From Thursday an exemption is no longer available under CARS if an insurer alleges contributory negligence in an accident of greater than 25%.

Claims assessors must now take into account whether a claim involves issues of liability including contributory negligence, fault and cause.

“The MAA is taking a holistic approach to the issues raised in the 2013 Smalley decision of the Supreme Court, through a range of complementary changes to help support desired CTP scheme outcomes,” the authority says.

“That court decision changed some of the previous understandings about the requirements for making liability decisions by insurers, their impact and their relationship to applications for exemption from assessment at CARS.”

The MAA says the guideline changes are part of a package of measures to improve CTP scheme outcomes, including new templates for insurers, workshops on liability decision-making, supporting guidance material and ongoing monitoring and reporting.