Billionaire Clive Palmer will challenge political donation caps in the High Court despite spending hundreds of millions of dollars on a failed election tilt.
Electoral reforms will cap the amount parties and candidates can spend at elections and the amount individuals can donate to political parties.
Mr Palmer said the laws impinged on political freedoms.
"We all have to have an appreciation and tolerance about everybody's right to express their opinion," he told reporters in Canberra on Wednesday.
Special Minister of State Don Farrell said Labor would defend the laws in the High Court, adding it would fight to curb the influence of big money in politics.
"We look forward to defending any challenge to these reforms," he said.
"Billionaires shouldn’t be able to use our democracy as their playground."
Mr Palmer's Mineralogy was the biggest third-party spender at the 2025 federal election, pumping almost $200 million out the door in the financial year, including more than $50 million for the campaign alone.
The coalition received spent almost $215 million in that financial year, which included the federal election in May, while Labor spent $160 million.
The Australian Electoral Commission data doesn't break out specific election spending for political parties as it does for third parties.
Labor won a resounding majority of 94 seats in the lower house while the coalition was diminished to 43.
But Mr Palmer's right-wing populist Trumpet of Patriots party failed to win a single seat.
Mr Palmer defended his major spending when asked about a comparison to One Nation, which won three Senate spots in 2025 despite spending $3 million.
"Money doesn't do it, it's ideas," he said.
"I spent $53 million, didn't get a representative. Well, if I spent $53 million, I should have got lot, shouldn't I?"
Independents have also criticised the donation caps and public funding earmarked for incumbents, saying it makes the field uneven for new challengers and those not backed by large political parties.
The donation law changes will take effect from mid-2026.
They cap the amount an individual can donate to a party's branch at $50,000 in a calendar year and limit election spending to $90 million for political parties nationwide.
There are also individual spending caps for candidates in each electorate and Senate races.
Independents say this stacks the field against them as major parties can use the nationwide war chest on general advertising and campaigning while they're constrained by their seat limit.
Further, the $50,000 individual donor cap per year can be extrapolated for parties with state and territory branches as well as a national arm, so they can receive up to $450,000 a year while an independent running in a single seat would be limited.
The Centre for Public Integrity criticised the reforms for not addressing corporate influence and providing full transparency over where money came from as it estimated almost $120 million in political party income 2024/25, about a quarter, had no attributed source
"They create inequality in our political system by advantaging major party and incumbent candidates over others without genuinely addressing the way wealthy interests can disproportionately influence the political process," executive director Catherine Williams said.
