Proportionate liability is a critical legal principle in Australia. It is particularly relevant in cases involving multiple parties responsible for economic loss or property damage.
This article was written by our commercial contract lawyer. The article explores the frameworks, principles, and practical implications of proportionate liability. It offers insights for businesses, legal professionals, and individuals navigating this complex area of law.
Key Takeaways
- Proportionate liability ensures that each party is only responsible for the portion of loss or damage they caused
- Governed by Federal and State laws, including the Civil Liability Act 2002 (NSW) and Wrongs Act 1958 (Vic)
- Landmark decisions such as Hunt & Hunt Lawyers v Mitchell Morgan Nominees Pty Ltd have shaped its application
- Parties can agree to exclude proportionate liability in contracts in some States and Territories, but this may have insurance implications.
- Proportionate liability influences litigation strategies, settlements, and risk allocation among defendants

What is Proportionate Liability?
Proportionate liability is a legal framework that allocates responsibility among multiple parties based on their contribution to the harm or loss. Unlike joint and several liability, where one defendant can be held liable for the entire loss, proportionate liability ensures that each party is only accountable for their share.
Proportionate liability:
- applies to economic loss and property damage, but typically excludes personal injury claims
- enables courts to assess the degree of fault of each party
- does not apply to intentional or fraudulent conduct
Legislative Frameworks Governing Proportionate Liability
Federal Legislation
- Competition and Consumer Act 2010 covers misleading or deceptive conduct under Part VIA
- Corporations Act 2001 addresses liability in financial and corporate contexts
State and Territory Legislation
Each jurisdiction has its own laws governing proportionate liability. Below is a summary:
Jurisdiction | Legislation | Key Provisions |
New South Wales | Civil Liability Act 2002 (NSW) | Part 4 outlines proportionate liability. |
Victoria | Wrongs Act 1958 (Vic) | Part IVAA governs apportionable claims. |
Queensland | Civil Liability Act 2003 (Qld) | Provisions for economic loss claims. |
Western Australia | Civil Liability Act 2002 (WA) | Part 1F applies to property damage claims. |
South Australia | Law Reform (Contributory Negligence and Apportionment of Liability) Act 2001 (SA) | Part 3 governs liability apportionment. |
Key Court Cases Shaping Proportionate Liability
Hunt & Hunt Lawyers v Mitchell Morgan Nominees Pty Ltd [2013] HCA 10
This case clarified how courts determine the extent of each party’s contribution to misleading conduct. The High Court emphasised that liability must align with the degree of fault.
Reid v Amaca Pty Ltd [2020] VSC 276
In this asbestos-related case, the court apportioned liability between two manufacturers based on their respective contributions to the plaintiff’s mesothelioma.
Ingrid Stephenson v Parkes Shire Council [2015] NSWSC 719
This case involved a helicopter crash caused by multiple failures, with liability apportioned among the aviation company, council, and powerline owner.

Practical Implications of Proportionate Liability
Impact on Businesses
Proportionate liability impacts businesses in the following ways:
- it encourages businesses to assess and manage risks more effectively
- defendants may contest claims more vigorously to limit their share of liability
- contracting out of proportionate liability may affect insurance coverage
Impact on Settlements
Proportionate liability often complicates settlement negotiations, as parties must agree on their respective contributions to the loss.
Contracting Out of Proportionate Liability
Parties can agree to exclude proportionate liability in their contracts. However, this requires careful consideration of:
- insurance coverage, as some insurance policies may not cover losses arising from contracting out
- indemnity clauses and contracts to ensure clear allocation of liability between parties
Frequently Asked Questions (FAQs)
What is the difference between proportionate liability and joint and several liability?
Proportionate liability limits each party’s responsibility to their contribution to the loss. On the other hand, joint and several liability allows a claimant to recover the full amount from any one defendant.
Can proportionate liability apply to personal injury claims?
No, proportionate liability generally applies only to economic loss or property damage claims. Personal injury cases typically fall under joint and several liability.
Can parties contract out of proportionate liability?
Yes, parties can agree to exclude proportionate liability in their contracts, but this may have implications for insurance coverage and risk allocation.
How do courts determine each party's contribution to the loss?
Courts assess factors such as the degree of fault and the relative importance of each party’s actions in causing the harm.
What are the key legislative frameworks for proportionate liability in Australia
Proportionate liability is governed by Federal laws such as the Competition and Consumer Act 2010 and State laws like the Civil Liability Act 2002 (NSW) and Wrongs Act 1958 (Vic).