ACC will appeal a ruling that a man who suffered post-traumatic stress disorder after helping Christchurch earthquake victims was acting as an employee when he did so.
Auckland District Court ordered the organisation it to compensate builder Bill Toomey two weeks ago.
Mr Toomey was diagnosed with PTSD two years after he rushed to the shattered Pyne Gould building to help people trapped following the 2011 Christchurch earthquake.
ACC said Mr Toomey would be able to keep his full entitlements regardless of the outcome of the appeal.
It had turned down Mr Toomey's claim, saying he was ineligible because his injury had not been caused at work.
Under the law, the definition of employment involves pecuniary gain, and Mr Toomey was a volunteer at the time of the injury.
An ACC spokesperson said it would appeal to the High Court to clarify the law, and wanted to know how the two could be reconciled.