The premier's hand-picked director-general was sacked in February amid allegations there was official misconduct over the hiring of the son of former arts minister Ros Bates, Ben Gommers, to a senior position in his department.
After an investigation spanning more than a year, the state's Crime and Misconduct Commission (CMC) announced on Wednesday it will not lay criminal charges.
It had referred a brief of evidence to the Director of Public Prosecutions in July.
The DPP has advised that any prosecution of Mr Caltabiano for alleged criminal offences would not have reasonable prospects of success, and therefore was not warranted.
"As such, the CMC will not take any further action in relation to Mr Caltabiano," a statement said.
Less than a fortnight ago, Mr Caltabiano was also cleared by the parliamentary Ethics Committee over allegations he lied about a prior business relationship with Mr Gommers.
Mr Caltabiano, a fellow councillor with Premier Campbell Newman when at the Brisbane City Council, had been on leave with pay for four months before he was sacked.
He made more money after he was sidelined from his position than when he actually worked, pocketing $652,947 for less than a year's on the job.
Comment has been sough from Premier Campbell Newman, but Ms Bates has declined to comment.
news.com.au 4 Dec 2013
Speeding fines should also be dismissed, as they are unlawful and (as put) for alleged criminal offences would not have reasonable prospects of success.