UPDATE: "INSIDERS" will be among those to give evidence at a Commission of Inquiry into Queensland's health payroll debacle.
Former premier Anna Bligh, former Labor Cabinet ministers and others involved in the system's implementation also could be summoned to testify at the $5 million inquiry, which will have royal commission powers.
Premier Campbell Newman said people involved in local trials, who spoke out about the failed system before it was rolled out state-wide, had approached him about telling their stories and other "insiders" were prepared to become whistleblowers if they were given indemnity.
Thousands of public servants were underpaid, overpaid or not paid at all after the failed IBM computer system was introduced in 2010.
Former Court of Appeal Justice Richard Chesterman, who has been appointed to head the inquiry, said he believed there was public interest in ascertaining where the public administration went wrong and he would undertake to find the answers.
"I expect there'll be a great deal of preparation work before the public hearings but I anticipate as much will be public as possible," he said.
The inquiry will run from February 1 to April 30 next year but could be extended if the commissioner needs more time to complete his task.
Premier Campbell Newman insisted this inquiry was not throwing good money after bad.
He said the inquiry was about getting to the bottom of the failed health payroll system implementation which a KPMG report he commissioned showed would cost Queensland taxpayers at least $1.25 million.
"It's an investment in the future procurement of IT projects but also I don't think you can put a price on openness and transparency," he said.
"There is this constant drip feed of people saying 'we said they shouldn't go live', 'I want to tell my story but I'm frightened of prosecution'.
"We want these people to come forward so we can get the facts on the table."
Health Minister Lawrence Springborg said the government had to spend $150 million a year, above what was budgeted, to run the health payroll system.
He said that equated to 1500 of the jobs which had to be cut from State Government ranks since they entered office nine months ago.
Mr Springborg said he could not talk openly about the legal advice he had received since Opposition Leader Annastacia Palaszczuk released secret Cabinet documents about Labor's negotiations with IBM
He said any successful legal action could depend on "yet to be discovered facts" which could come from the inquiry.
Attorney-General Jarrod Bleijie said the general statute of limitations could expire at the end of 2013 but there could be a later date depending on what potential prosecution developed.
He said the inquiry would look at how the "mess" unfolded including the government procurement processes adequacy, who was to blame and any possible recourse in the future.
Mr Bleijie said the inquiry also would set a framework for the future to ensure this would not happen again.
Opposition leader Tim Mulherin called on the government to release the legal advice it had received about possible legal action and how much it planned to recoup the money.
He said Labor had nothing to fear from an inquiry, arguing everything was already out in the open.
Newman to announce details of health payroll inquiry
A COMMISSION of Inquiry to investigate the health payroll debacle will begin next year.
Premier Campbell Newman is expected to announce the details of the flagged inquiry, which could include Royal Commission powers, at 10.45am.
The failed IT program has resulted in health staff being overpaid, under paid or not paid at all since it went live in 2010.
The payroll system is believed to have cost taxpayers millions to dollars unsuccessfully trying to fix it.
Update your news preferences and get the latest news delivered to your inbox.