A ban on property developers making donations to political parties introduced by the Queensland government has been upheld by the High Court.
Lawyers for former Liberal National Party state president Gary Spence told the court during a March hearing the Queensland laws went too far because they could affect donations used in federal polls.
However, the court ordered on Wednesday ruled the Queensland provisions were valid.
It also found a section of federal electoral laws was invalid.
That section potentially opened a loophole allowing developers to donate to state party branches to be spent on federal campaigns.
Reasons for the High Court's orders will be released at a later date.
The state laws began operating in October 2018 following an anti-corruption investigation, and also cover industry representative organisations.
That Crime and Corruption Commission investigation looked at councils, and recommended the state government ban property developer donations at a local government level.
Challenged on why the state government had applied the recommendations beyond councils, Deputy Premier Jackie Trad said: "We believe if its good enough for one level of government it's good enough for all levels of government."
The laws make it a crime for a developer to make a political donation, a person to make a donation on behalf of a developer, or a person to accept a political donation made by or on behalf of a developer.
In its submission, the federal government said the Queensland scheme was indistinguishable from that operating in NSW, which was found to be in line with the constitution in 2015.
The Queensland government says the laws help prevent corruption.
The LNP says they are unfair because they don't include donations from trade unions and that therefore they are purposefully singled out.
"We still believe that these laws are politically motivated from the Palaszczuk government," the party's Deputy Leader Tim Mander said.
Acting Attorney-General Stirling Hinchliffe called on Prime Minister Scott Morrison and state LNP leader Deb Frecklington to disclose their donations.
Mr Spence announced his resignation as LNP president in December last year, blaming the new laws, as he was also chairman of engineering consultancy firm PeakUrban.
He argued this would make him a "prohibited donor" subject to hefty fines and even prison time if he stayed in both roles.
Australian Associated Press