ACC says anyone who became ill from the Havelock North water contamination crisis won't receive cover.
The agency argues that because the gastro outbreak was neither an accident or a criminal offence it won't offer cover.
But a lawyer says that's wrong and it's not fulfilling its intended duty.
More than a year after the gastro outbreak the long term impacts of the illness are still crippling Carol Hessell.
"There are days that I sit here and cry the pain is so bad," she said.
She was put in intensive care after drinking tap water contaminated with campylobacter in August 2016.
Her illness developed into reactive arthritis. She's now in constant pain and needs a walker.
"I get caught short toilet end and the bowel end quite often and I can't always judge that, I do get caught short," she said.
Ms Hessell requested help from ACC after the outbreak but was declined cover.
"They said because it wasn't a definite accident but I don't know how else would you describe it," she said.
ACC today announced no one impacted by the Havelock North outbreak, in which 5500 became ill, would be entitled to cover.
Ms Hessell is one of seven people turned down by ACC.
ACC says it won't cover the claims because the ingestion or inhalation of bacterium is not considered an accident unless it is the result of a criminal act.
It went on to say that although the district council had paid a fine a criminal act had not taken place.
ACC also says a court must determine when a criminal act has taken place.
However, ACC lawyer John Miller told Newshub that's wrong, ACC should instead look at its purpose to help those who are injured.
He argues that a criminal act should also include breaches of regulation and would support anyone wanting to challenge ACC.
There is a possible silver lining for Ms Hessell, the district and regional council have a set up a $200,000 fund for those who fell ill.
That money is expected to be dished out by Christmas.
Newshub.