The High Court will rule on Wednesday whether Queensland's ban on property developers making political donations breaches the Australian constitution.
However the reasons for the orders won't be immediately released.
The state laws began operating in October 2018 following an anti-corruption investigation and also cover industry representative organisations.
They 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.
Lawyers for former Liberal National Party state president Gary Spence told the court at a hearing in March the Queensland laws went too far because donations used in federal elections could be affected.
While donations from property developers are legal at a federal level, Jeremy Kirk SC, for Mr Spence, argued money given to state branches of political parties and used for national polls could be captured by the laws.
Mr Kirk said the federal government had not banned developer donations, noting recent reforms which prohibit foreign money flowing into federal politics.
He said if both the Commonwealth and states regulated donations, federal laws should have precedence.
Mr Kirk also argued the laws undermine the federal government's exclusive power to regulate federal elections.
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.
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.