HSU boss 'compliant' to Williamson

Taped phone calls have revealed the head of the Health Services Union was "entirely compliant" to orders from his disgraced predecessor Michael Williamson.

Unions whistleblower Brian Fitzpatrick has been called "a crusader" seeking to bring the CFMEU down. (AAP)

Recorded phone calls have revealed disgraced Health Services Union (HSU) boss Michael Williamson giving orders about the running of the union months after he supposedly relinquished control.

In calls played at the unions royal commission on Wednesday, Williamson directed his replacement as HSU East branch general secretary, Peter Mylan, to discourage another union official from speaking to the police.

Williamson was jailed in March for five years for defrauding millions of dollars from the HSU.

The calls were recorded in February 2012 by police investigating Williamson, who stepped down as union leader in September 2011.

In one conversation, Williamson directs Mr Mylan to organise a meeting where the union's lawyers could tell a divisional secretary, Gerard Hayes, not to speak to police on his own.

"You get a meeting with him, Phil and John ... and they say, 'Mate, you can't do that'," Williamson said.

In another call, Williamson dictates to Mr Mylan the wording of a resolution to be put to a union council meeting to prevent observers appointed by his rival, whistleblower Kathy Jackson, being present.

Counsel assisting the commission Jeremy Stoljar SC said Williamson was clearly giving directions to Mr Mylan.

"And you were entirely compliant with his directions, that's right, isn't it," Mr Stoljar said.

Mr Mylan agreed he was but said he was seeking Williamson's union experience.

The Royal Commission into Trade Union Governance and Corruption returned its attention to the HSU after earlier hearing about the treatment of a whistleblower in the Construction, Forestry, Mining and Energy Union (CFMEU).

Brian Fitzpatrick, a former CFMEU official, has given explosive testimony that he received a death threat after complaining the union was giving favourable treatment to companies run by underworld figure George Alex.

In cross-examination, counsel for the CFMEU John Agius accused Mr Fitzpatrick of making up evidence, including his claim that union organiser Darren Greenfield threatened to kill him during an enraged outburst in a phone call.

"You see yourself as a crusader who can bring the union down?" Mr Agius asked.

Mr Fitzpatrick replied: "Don't be so stupid. That's exactly the opposite of what I'm about."

The hearing resumes on Thursday.