ACTU chief Ged Kearney with an unfortunate turn of phrase - reported in the AFR.

“Australians are very cynical about this,” she told reporters in Melbourne.

“They’ll know this for what this is. This is nothing but a witch-hunt designed to weaken unions to stop unions standing up for decent wages so that Australians can maintain a decent standard of living.”

Ms Kearney said the government would spend $100 million on the royal commission “for their own political purposes”, when it should be police who probe union corruption.

She linked the commission to the coalition’s recent attack on “overgenerous” enterprise agreements at companies such as SPC Ardmona, and its Fair Work Commission submission calling for a rethink on penalty rates.

Ian Cambridge in The Australian.

Ian Cambridge, a serving Fair Work Australia commissioner and a former national secretary of the AWU, told The Australian yesterday: "I have been reluctant to engage in public commentary on this matter because of my role serving Fair Work.

"But I have steadfastly maintained my firm view since 1996 that a royal commission into this should occur. I have always believed that it should have occurred at the time and I am not changing my position now.

"Of course, I would obviously co-operate in any way I can. If I am asked, I will co-operate fully."

Mr Cambridge, who took a rare step for a judicial officer 12 months ago in calling on witnesses to offer evidence to an ongoing Victoria Police fraud squad investigation into the slush fund, has named his former AWU boss, federal president Bill Ludwig, among those who should help police.

Bill Ludwig - as reported in The Australian.

Mr Ludwig, who once backed Mr Cambridge's efforts to have the corruption investigated, then supported Ms Gillard in her quest to be prime minister. He has said the reporting and investigation of the fund is a smear campaign.

Ralph Blewitt - reported in The Australian.

Another former AWU official, Ralph Blewitt, said from Malaysia yesterday that the royal commission, to be led by retired High Court judge Dyson Heydon, was essential to expose what he described as the corrupting influence of unions on Labor politics.

"I believe it will uncover a lot more in the AWU slush fund scandal and it will expose other very corrupt union practices," said Mr Blewitt, a confessed fraudster who was Mr Wilson's sidekick, as well as a client and friend of Ms Gillard in the 1990s.

"It will show the Australian public where the corruption is and how there is no dividing line between the union and the Labor Party: they are one and the same.

"I stand ready to give evidence and to co-operate at any time. If at the end of the day it results in me being charged and found guilty in court, I will take my medicine."

Adam Bandt, The Greens (former Slater and Gordon lawyer) - reported in the AFR.

The Australian Greens also called for a police investigation, saying a royal commission would backfire.

“The Australian people will see (a royal commission) for what it is, the first step in the government’s assault on wages and conditions,” Greens deputy leader Adam Bandt said.

Brendan O'Connor, Labor's IR shadow (and brother of Gillard ex and CFMEU chief Michael O'Connor) - reported in the AFR.

Labor’s workplace relations spokesperson Brendan O’Connor questioned the need for a royal commission.

“This seems to be a highly politicised, very expensive exercise,” he told ABC television.

He said that when Mr Abbott was workplace relations minister in the Howard government, he set up the Cole royal commission into corruption in the building industry in 2001.

“It cost $66 million of taxpayers’ money. It did not lead to one serious criminal conviction,” Mr O’Connor said.

Bill Shorten on the ABC.

Labor is opposing the royal commission, which it says is politically motivated, and favours a police taskforce instead.

Opposition Leader Bill Shorten says no-one is above the law and that criminal issues are a matter for the police.

He has also attacked the cost of the mooted royal commission.

"The idea that we need to have an expensive multi-million-dollar political royal commission, rather than give those scarce resources to our hardworking police, means the wrong priorities," Mr Shorten told the ABC.