CFMEU Qld secretary Michael Ravbar had been “reckless” over the payment of redundancy and hardship funds to striking workers, a royal commission was told.

A retired High Court judge heading a royal commission into unions has rebuked a construction union leader for being “reckless”, after he justified the payment of redundancy and hardship funds to striking workers.

Michael Ravbar, the Construction Forestry Mining and Energy Union’s Queensland and Northern Territory secretary, was asked on Wednesday why these funds in August 2012 were spent on Abigroup workers, who had been on strike for four weeks at the site of Brisbane’s new children’s hospital.

Mr Ravbar, a CFMEU-appointed director of the Building Employees Redundancy Trust, was being crossed examined by the inquiry’s senior legal counsel Jeremy Stoljar.

“It’s their money, their entitlement to get it,” Mr Ravbar told the inquiry sitting in Brisbane for the third day.

This prompted royal commissioner Dyson Heydon, a retired High Court judge, to rebuke the union leader.

“That’s a rather reckless thing for the director of a trustee to say,” he said.

“Trustees do have to be careful.”

Before Mr Ravbar entered the witness box, several hundred unionists risked $10,000 fines to demonstrate solidarity with him, after Universal Cranes had told the inquiry his union had pressured their clients in 2012.

His witness statement, denying those allegations, was released shortly before lunch.

“At no stage did the CFMEU block Universal Cranes from entering worksites,” Mr Ravbar said.

“The CFMEU did not approach Universal Cranes’s clients, it was the other way around.”

Universal Cranes boss Albert Smith on Monday accused the CFMEU of encouraging clients to boycott his company until he gave in to union demands on enterprise bargaining and a multimillion-dollar redundancy scheme.

Before entering Brisbane Magistrates Court, Mr Ravbar told rallying construction workers the royal commission was a witch hunt against unions.

“I plan to go to the court and provide a balanced view of what the trade union movement is all about, to highlight that there is no criminality and corruption,” he said.

His rallying comrades were warned by the Fair Work Building and Construction (FWBC) agency they could face penalties of up to $10,200 if construction sites were shut down for the rally.

“Their conduct may also constitute unprotected industrial action, which is illegal,” the agency’s director Nigel Hadgkiss said in a statement on Wednesday, adding it would not hesitate “to bring people before the court where necessary”.

Employers or unions can also be penalised up to $51,000 for being involved in paying or demanding strike pay.

Master Builders Australia echoed the FWBC’s sentiments on Twitter: “Are these employees on leave? On strike? RDO?” The inquiry resumes on Thursday.