Motorcyclists gathered at the High Court in Christchurch this week to challenge the legality of Accident Compensation Corporation (ACC) levy increases. Led by representative Chapple, the legal proceeding argues that the methodology used to calculate risk-based levies for motorcycles is irrational and procedurally unfair. While the court will determine the legality of the decision, Chapple is seeking interim orders to block the price hikes until a final ruling is delivered.
Why are motorcyclists challenging ACC levy structures?
The legal challenge focuses on whether ACC’s method for allocating costs is supported by available data. According to MAGNZ spokesperson Richard Tohu, the primary issue is the use of engine capacity as a proxy for risk. Tohu argues that while ACC applies engine-size surcharges to motorcycles, it does not apply the same logic to high-performance cars. “A high-powered performance car driven by a young driver has a very different injury-cost profile from a small hatchback, yet ACC makes no distinction,” Tohu stated.

The current challenge does not seek to stop motorcyclists from contributing to the ACC scheme entirely. Instead, it questions why engine size is used as a risk-rating metric for bikes but ignored for other vehicle classes.
How does engine size impact rider levies?
Proponents of the legal challenge, including long-time rider Graham Sayer, contend that engine displacement does not equate to crash frequency. Sayer, who suffered a leg injury while riding a 250cc motorcycle, noted that he now pays higher levies for a 1000cc bike despite his injury history occurring on a lower-capacity machine. “It’s not right that I’m having to pay extra for the higher cc rating,” Sayer said. He contrasted his situation with a V12 Lamborghini owner, who pays no additional registration surcharge based on engine size.
What are the next steps for the legal proceedings?
The immediate goal for the plaintiffs is to secure interim orders that prevent the levy increases from taking effect while the court reviews the case. This follows a series of public demonstrations, including a mass ride-along in Auckland earlier this year. The court must now weigh whether ACC’s internal decision-making process met the required standards of lawfulness and rationality. If the court finds the methodology flawed, it could set a precedent for how ACC justifies levy distinctions between different vehicle categories in the future.
Comparison: Motorcycle vs. Car Levy Methodology

| Criteria | Motorcycles | Passenger Cars |
|---|---|---|
| Engine Size Surcharge | Applied | Not Applied |
| Risk Assessment Basis | Disputed (Capacity-based) | General Class |
Frequently Asked Questions
- Are motorcyclists asking to pay nothing to ACC? No. The challenge focuses on the fairness and legality of the calculation method, not the requirement to contribute.
- What is the main argument against the current levies? Riders argue that engine capacity is an unreliable metric for risk and that it is applied inconsistently compared to other vehicle types.
- What happens if the court rules in favor of the motorcyclists? The court may order ACC to revise its methodology or halt the implementation of the specific levy increases.
What are your thoughts on using engine size to calculate vehicle levies? Join the discussion below or subscribe to our newsletter for updates on this unfolding legal challenge.
