The Queensland corruption watchdog won't investigate the opposition's claim Deputy Premier Jackie Trad engaged in an act of "extortion" against mining companies.
Ms Trad told miners last month she wouldn't raise coal royalties for three years if they volunteered to put $70 million into a new regional infrastructure fund.
Opposition leader Deb Frecklington said it was essentially a $70 million ransom note.
She asked the Crime and Corruption Commission to investigate whether the circumstances that led to the fund may constitute an offence of extortion.
The CCC on Friday said it was not going to investigate.
It said they had assessed the complaint and determined the conduct did not raise a reasonable suspicion of corrupt conduct.
The CCC said even if the conduct was proven, they did not think it would satisfy the elements of a criminal offence, including extortion.
Ms Trad did not increase coal royalties in this week's budget, but has said the issue would be revisited next year if miners don't sign up.
Australian Associated Press