THE fight to destroy the Federal Government's mining tax has a "snowball's chance in hell" of success, according to a Brisbane law expert.
The Queensland Government this week joined iron ore giant Fortescue Metals Group's High Court constitutional challenge against the Mineral Resource Rent Tax.
Attorney-General Jarrod Bleijie said entering the fray would cost the state about $300,000.
The Western Australian Government also will make submissions to the case, but not directly join the fight.
Queensland University of Technology constitutional law lecturer John Pyke - who is currently writing a textbook on the subject - said while these challenges were often winnable, he described this as "one of these political constitutional challenges".
"It's to show they are fighting the big, bad federal government wolf," Mr Pyke said.
"In the (former Premier Joh) Bjelke-Petersen days, they would challenge every second Act the government put through."
To be successful, the Federal Government's challengers would have to prove that taxing mining profits amounted to a form of discrimination between states.
Failing that, they would need to show the MRRT was somehow affecting the state's ability to act like a state.
University of Queensland Professor of Public Law Suri Ratnapala was less willing to bet on the winner, but said the Federal Government was defeated in these cases "surprisingly often".
"Every few years there are some laws considered unconstitutional in their operation," Prof Ratnapala said.
"But every law of a controversial nature that the government wants enacted is very seriously considered by the Solicitor-General and other advisers to see if it is exposed to constitutional challenges.
"But it doesn't mean they will necessarily be immune from constitutional challenges or even immune from successful challenges.
"Government legal advice is often not the one adopted by the High Court."
Treasurer Wayne Swan told reporters on Monday the challenge was "futile".
The MRRT was put in place on July 1.
It is expected to deliver up to $10.5 billion to the Federal Government to increase superannuation and tax cuts for businesses. It will also be used to fund "community infrastructure".
The High Court challenge is not expected to be heard until early 2013.