The roots of that inequity reach to 1967, when a Royal Commission led by the late Sir Owen Woodhouse called for a new system to give proper care and support for the impaired.

“A man overcome by ill health is no more able to work and no less afflicted than his neighbour hit by a car,” the Woodhouse report concluded - but, given the reform’s “massive leap”, it recommended covering injuries as a first step.

ACC was born in 1974, and claims have since boomed to more than 2 million a year.

“The system has been gamed on all sides, to shift people into the system - claimants, treatment providers, lawyers, everyone involved...it’s developed into an alternative to the public health system,” says Dunedin lawyer Warren Forster.

“If you don’t get ACC help, and your family can’t cope or doesn’t cope, or your partner leaves, or any of these other things happen, then you are really on your own. And that’s a hard place lots of New Zealanders have found themselves in.”

Forster will soon release research, funded by a prestigious Law Foundation fellowship, which will argue for, before 2040, a new system delivering equal, ACC-like support to everyone with an impairment, eventually expanding to a full health and social insurance model.

One funding option is to massively grow the more than $44b investment fund that generates about $5.1b of ACC’s total annual income of $9.6b.

How to meet the enormous cost would be up to politicians, Forster says - borrow cheaply, plough back investment returns, use the tax system, levy earnings, or a combination.

There’s some political will - Green Party policy is to create an “Agency for Comprehensive Care”, delivering equitable support to everyone with a work-impairing disability or health condition.

Others are speaking out.

“An increasing number of people in Parliament are acknowledging the two-tier systems shouldn’t continue, so I hope some movement can be made on it,” says Ruth Dyson, who retired as a Labour MP at the election and is a former ACC and disability issues minister.

Asked about affordability, Dyson says, “the cost is the same”.

“It is actually who bears the cost. At the moment the individual person bears the cost. And most New Zealanders would probably think that wasn’t appropriate.”

Her former colleague Iain Lees-Galloway was ACC Minister from October 2017 to July 2020, and in his valedictory speech the following month offered “thoughts from someone with the luxury of not seeking re-election”.

“ACC is a taonga and we don't know how lucky we are to have it. But we politicians have decided that ACC should be limited to covering injury, whereas illness is covered by the health system,” said Lees Galloway.

“I will never forget meeting with a constituent who lost three limbs to meningitis, who rightly pointed out that if she had lost those same limbs in a car accident she would have been considerably better off financially and would have received superior treatment and support.

“That is impossible to justify. Health should also be run as a social insurance scheme, and New Zealanders should expect the same support whether they are injured or they fall ill.”

Brendon Bowkett operates on children with serious conditions like spina bifida, which can cause paralysis. By the time they’re teenagers such patients endure, on average, about 20 operations.

Care between surgery is crucial, but too often children fall into “Grand Canyon areas of neglect in rehabilitation services”, he says.

One example is hydrotherapy (water exercise), which allows children to feel weightless. An “appalling” number can’t access it, he says, and it’s infrequent for those who do.

Similar concern about child cancer services in the 1990s brought in a “service specification” - international specialists toured NZ with local counterparts, and treatment benchmarks were agreed with the government.

“Today we have outcomes for children that are similar to the best in the world, even in underprivileged groups,” Bowkett says. “That’s never been done with rehabilitation.”

Within the substandard overall system non-ACC kids can get significantly less help, he says. And many wouldn’t be disabled if successive governments hadn’t failed to take public health steps, including requiring car booster seats up to age 11, fixing perinatal services and fortifying flour with folic acid to slash birth defect rates.

“If they addressed those areas, the savings alone would fund a world-class rehabilitation service.”

Another specialist, who asked to remain anonymous in order to speak freely, gave an example of the ACC divide; an 8-year-old who becomes fatigued as a result of a stroke years earlier, which causes him to become aggressive and harm a younger sibling.

Because his IQ is above 70 (somewhere between 2 and 3 per cent of people are below this marker) there’s no behavioural support, or help from other agencies and services.

A similarly disabled child under ACC - from a car accident, for example - would get co-ordinated care, including neuropsychological assessments and behavioural interventions. A teacher aide may be funded.

“He has a brain injury as impairing as other children who sustained injuries accidentally,” the specialist says.

“In many ways, if you have the misfortune to have a stroke as a child, you might want to consider jumping in front of a bus to get a decent rehabilitation and care package.”

Wellington-based playwright and poet Henrietta Bollinger understands such frustrations.

A twin, her cerebral palsy developed in pregnancy, meaning she’s on the Ministry of Health/DHB side - something that can mean less responsive help.

One example: her funded electric wheelchair can’t be used in many situations, including when negotiating the capital’s steep driveways, paths and stairs, and doesn’t fit in non-adapted vehicles. So far, the ministry hasn’t funded a secondary, more versatile chair, meaning she regularly uses her old one, which she’s outgrown and is uncomfortable.

Another: home modifications were funded, but those were done when she was 8. Now 27, she’s long since moved out.

Entitlements also vary between DHBs. However, Bollinger, who works in disability rights advocacy, says she knows ACC isn’t perfect either , and focusing on the division can be unhelpful.

“You end up having to use what energy you have on asking, ‘Why are some people supported to this degree, and others to a lesser degree?, as opposed to having a more aspirational conversation.

“It pushes the disability support conversation into this space of, ‘How much are people’s individual needs going to cost?’ And it boils the conversation down into something sort of mercenary.

For now, causation is king.

In Leonie Metcalfe’s case, bureaucrats wanted her to pinpoint which breath of air decades earlier led to her terminal cancer.

Her diagnosis came after she mentioned shortness of breath to her GP. A CT scan on July 31 revealed pulmonary mesothelioma - cancer in the tissue lining the lungs, caused by inhalation of asbestos fibres years earlier.

The disease is aggressive (the average survival time is about 12 months) and mostly affects builders and tradies.

Metcalfe has worked for 50 years as a nurse, currently at Waikato Hospital and formerly at Wairoa Hospital in the Hawke’s Bay.

Both had building work possibly involving asbestos during her employment, but as a nurse she was considered low-risk of exposure, and after to-and-fro ACC indicated her application would probably be declined.

That was despite no other ready explanation - she hadn’t herself done home renovations, and her husband isn’t a builder or tradie (people have been exposed when washing their partner’s work uniform, for example).

“I’m 68 at the moment, but they say I was probably exposed to asbestos in my 20s or 30s. When you look back close to 40 years, hell, I wouldn’t even know what I was doing back then, let alone thinking of asbestos.”

Her claim was eventually accepted after seeking legal advice and continuing to challenge the decision. She’ll get a lump sum payout, and, if she chooses to give up the work she still loves, a portion of her wages.

Depending on medical advice, Metcalfe might use the windfall to cover life-extending immunotherapy drugs, which aren’t funded by Pharmac and cost over $100,000 a year.

(Her lawyer, Beatrix Woodhouse, was at a Court of Appeal hearing last week, after ACC challenged a High Court ruling in favour of another client, since deceased, who inhaled asbestos as a child when hugging her electrician father. ACC had previously covered work-related mesothelioma. If upheld, the decision will create binding precedent, expanding cover to secondary exposure.)

Metcalfe’s medical knowledge and determination means she could, eventually, navigate the system. She worries for those unable to.

“I have an amazing family and colleagues who are really, really supportive, but a lot of people don’t have that. They are the people I really feel sorry for – those who get what they’re given, accept what they’re told and don’t challenge things.”