When Hunter Valley local Wendy Wales got together with a few of her neighbours to oppose a new open-cut mining operation on their doorstep in 2016, she had no idea it would instigate a years-long legal tussle with the potential to become what one litigation expert has described as "a watershed moment in the history of Australian law".

Today, the retired science teacher and her fellow farmers and Muswellbrook locals - now backed by some powerful legal forces including four of the world's leading climate law and science institutions – will put their case before the High Court of Australia.

The case centres around the community group's opposition to the proposed expansion of the Mount Pleasant mine, owned by a subsidary of Indonesian billionaire Anthoni Salim's mining conglomerate, MACH Energy Australia.

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But if the High Court upholds their case, the ramifications will reach far beyond just one mine, setting a nation-wide legal precedent that could throw plans for more than 18 coal proposals in New South Wales alone into doubt.

Professor of Climate Law at Bond University, Professor Nicole Rogers, has lent her voice to the community group's legal case.

"Australia's apex court hearing its first climate change case is a watershed moment in the history of Australian law," she said.

"Courts around the world – from The Hague to London to Canberra – are being asked the same fundamental questions."

Despite the daunting scale of the legal battle, Wales remains optimistic that the High Court will rule in the group's favour.

"The time is five minutes to midnight for Australia… We wish it would have happened 25 years ago," she said.

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At the crux of the DAMSHEG (Denman Aberdeen Muswellbrook Scone Healthy Environment Group) group's argument is whether planning authorities are legally obliged to consider the local climate impacts of the coal that a mine exports overseas when analysing the impacts of a new project.

Over the past 25 years with her partner Tony Lonergan on his family's 600-acre property adjacent to the Mount Pleasant mine, Wales has witnessed Australia's altering climate first-hand, with weather extremes becoming more frequent and more severe.

After living through the Millennium drought, which brought many farmers to the brink, the community was wracked by devastating bushfires and multiple "one-in-100-year" floods in the space of just a few years.

Just last year, the May floods impacted their property and washed away part of their creek.

"It held for all the previous rain events, but this one, we lost probably about six or seven metres of bank," Wales said.

In fact, their property and others like them are now deemed such a natural disaster risk that Wales and Lonergan struggled to obtain home insurance and were forced to switch insurers.

"I personally know half a dozen people who have lost their houses in the last ten years," Wales said.

"I don't know people from the last century who lost their houses like this.

"They had insurance and they can start up again but they have really experienced something that is quite shattering."

Under the proposed expansion of the Mount Pleasant mine, its operating licence would be extended by 22 years – stretching the life of the mine out to 2048 and doubling coal production to 21 million tonnes per year.

The vast majority of that coal will be exported and burnt overseas, sending an additional 870 million tonnes of carbon dioxide into the atmosphere.

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Wales believes that if planning authorities were obliged to take the local climate and economic impacts of these emissions into account, the scales would tip against approving such projects.

Their case was shot down by the NSW Land and Environment Court in 2024 but in July last year, a panel of three judges on the NSW Court of Appeal unanimously overturned that ruling.

The landmark verdict came just hours after the United Nations' top court at The Hague ruled that countries could be in violation of international law if they fail to take measures to protect the planet from climate change.

Now, the Mount Pleasant mine's owners are appealing to the High Court.

Proponents of the mine's expansion have touted the new jobs it will bring to Muswellbrook and surrounding communities.

There are currently around 400 local workers employed at the mine, and the expansion would increase this to an average of 600 over the life of the mine.

A spokesperson from MACH Energy Australia said the company "welcomes" the opportunity to put its case to the High Court.

"(We) will continue to operate in alignment with existing approvals and conditions and seek to provide long-term continuity and certainty for its staff, contractors, customers and the local community," the spokesperson said in a statement. 

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Prime Minister Anthony Albanese insists a desire not to see Australia divided into those who own homes and those who don't as a reason for making sweeping reforms to negative gearing and capital gains tax in last night's budget.

In April 2025, Albanese resoundingly denied he would make changes to both ahead of the election, saying: "Yes! How hard is it? For the 50th time", when asked if he would rule out the changes.

Albanese defended his broken election promise, saying the government had to take action to tackle the issue of housing supply.

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"We've changed our position, I'm upfront about that," he said on Today, denying he had lied to the Australian population.

"We've changed our position because we're throwing absolutely everything at supply."

Under the changes, negative gearing, which allows home owners to deduct a net loss from a residential investment property from their overall income and lower their total taxable income, will be scrapped, while a 50 per cent discount on the capital gains tax payable will be rolled back.

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Albanese said the decision was "difficult", but was necessary to help young people get closer to the dream of owning a home.

"There's nothing more aspiring than the legitimate aspiration Australians have to own their own home," he said. "We can't sit back and watch a whole generation be locked out."

He clarified the changes wouldn't be coming into effect until next year, and that existing investments would be "grandfathered", meaning any property purchased until now would be protected from the changes.

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Responding to claims the changes would instead impact older Australians who already own homes, Albanese said he did not want Australia to be divided along lines of home ownership.

"I don't want to see a divided Australia which is divided into Australians who own homes – some multiple homes- and people who simply will never be able to achieve the dream and make it a reality of having a roof over your head," he said.

"What's changed as well is increasingly not just young Australians, but parents and grandparents… who say 'I'm worried about my kids and grandkids won't be able to own a home.'"

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A major change to how some older Australians receive their pension, an extra $10 fee for international travel and a looming rate-hike warning is buried in the 2026 Federal Budget papers.

The federal government delivered what it has described as its most significant budget of the 21st century, and aside from sweeping, generational tax reform, there are some key changes hidden in the thousands of pages.

Here's what else you might have missed.

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International passengers to pay more

Airlines and cruise companies will be made to pay an extra $10 for every passenger departing the country via air or sea.

The government's Passenger Movement Charge will be increased from $70 to $80 from January 1 2027, according to the 2026 budget papers.

It will be calculated on the date of departure, rather than the date of ticket sale.

Aviation sources previously warned that airlines would pass on the extra $10 to passengers.

The cost of slugging airlines with an extra $10 per passenger is forecast to increase revenue by $755 million over five years.

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Changes to aged care pension

The federal government said it is "modernising" the pension supplement paid to Australians who live overseas, a reform it said will deliver around $218 million in savings over the next five years.

Eligibility of the pension will shift to cease supplement payments for recipients who are permanently living abroad or who are absent from Australia for more than three months.

Before now, travellers had their full rate of the pension supplement suspended if they left the country for six weeks or more.

This provision has been extended by six weeks to a total of 12 months.

The pension supplement is an extra payment which is paid on top of the aged care pension which helps with utility, phone, internet and medicine costs.

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Borrowers should brace for another rate hike

The treasury has offered a grim forecast for mortgage holders after a triple rate hike blow was delivered in March, April and May.

It predicts that another cash rate hike is coming in September, spelling doom for households hoping for some interest rate relief.

The official cash rate target is now at 4.35 per cent.

If previous rate hikes are a guide, the big four banks and lenders are likely to pass on a September increase.

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Foreign investments ban extended until 2029

The federal government's ban on foreign purchases of existing homes will be extended until 2029, an extra two years and three months.

The Albanese government announced the ban during the 2025 Federal Election race, which aims to freeze out foreign buyers from purchasing already built homes.

This ban has been touted as the key to unlock thousands of properties for Australians.

Crackdown on visa misuse

This year's budget includes a $74.2 million allocation to crackdown on migrants attempting to misuse the protection visa system.

The Department of Home Affairs has previously warned against temporary visitors applying for a $50 protection visa – which is reserved for asylum seekers escaping persecution in their home country – in a bid to remain in Australia and continue working.

The department said it has noticed an uptick in temporary visa holders from the United Kingdom and Ireland being advised on social media to apply for a protection visa just to stay longer Down Under.

The bulk of this investment will be allocated to the Court of Australia and the Federal Circuit and Family Court of Australia.

Another $19.8 million will be given to the Department of Home Affairs to ensure the "overall integrity of the international student visa system".

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Electrifying Australia's car fleets

There will be an expected 25 per cent fringe benefits tax (FBT) discount for drivers who have bought an electric car which costs over $75,000 by April 2027.

All electric car owners will be able to claim the FBT discount by April 2029.

Up until now, your car needed to cost less than $75,000 to be eligible for this tax break incentive.

Despite a years-long debate over an EV road user charge, there is no mention of it in the 2026 budget papers.

Half a billion for bike and walking paths

The federal government will commit $50 million every year for a decade to construct or upgrade walking and bike paths across the country.

This amounts to a total of $500 million invested in making Australian cities walkable or bikeable.

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Media subsidies for ABC, SBS and AAP

A heavy investment will be made into Australia's national broadcaster to develop its Indo-Pacific broadcasting strategy.

The ABC will be given an extra $14.1 million over two years to build "production, distribution, capacity building, and media engagement activities in the region".

Meanwhile, the SBS will be offered a portion of a broader antisemtism and counter-terrorism package in the wake of the Bondi terror attack to extend its SBS Examines podcast series.

And the AAP will be allocated $15 million in this budget to ensure it remains financially viable.

'Nuisance' tariffs on margarine, tyres out the window

Another 497 "nuisance" tariffs will be abolished in a second tranche of reforms aimed at cutting costs and boosting productivity.

From July 2026, tariffs will be eliminated on various products including wine glasses, tyres, air conditioners, margarine, and bitumen.

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