An inquiry into the behaviour of the CFMEU in Queensland has been shown video of union members storming a government building to disrupt a conference discussing major projects, and shutting police out of the room.

Hundreds of CFMEU marchers took over a Queensland Transport and Roads Investment Program conference at a government building in the Brisbane CBD in August 2022, before storming the main meeting room.

CFMEU leaders Michael Ravbar, Jade Ingham and Paul Dunbar had been invited to attend the conference, but Ingham instead led the raucous group of union men into the building.

As the men pushed in, a building security guard was shoved to the ground.

Once inside, the group insisted they were registered guests, with Ingham convincing police to allow him to shut the conference room doors for some 15 minutes with the men and conference attendees inside.

At one stage, the chant “Neil Scales smells like corruption” could be heard, in reference to the director-general of Transport and Main Roads at the time.

A statement from a TMR employee who was in the building at the time said they were worried about Scales’ safety.

“The protesters were shouting, jeering, and their demeanour was boisterous, loud and unsettling,” counsel assisting Eddy Gisonda read to the inquiry on Thursday.

“The employee felt at risk from the aggressive, angry protesters, and concerned as the director-general was always on the floor in a meeting room.”

Another employee said she was angered that the department did not make a statement condemning the union’s actions.

“This has left me feeling vulnerable, as there appear to be virtually no consequences for any militant protesters who may choose to invade my workplace,” she said.

The video was shown during evidence being given by David Balmer, the local head of Spanish multinational Acciona, and chair of the Queensland Major Contractors Association, who was at the meeting.

He said then-transport minister Mark Bailey had been scheduled to attend the August conference, but did not show, leading to speculation he had been tipped off about the union action.

Balmer also recounted a “highly unusual meeting” at Queensland’s Parliament House with Bailey and TMR leaders, where Bailey had asked to be kept up to date with EBA negotiations on a Coomera Connecter project run by Acciona.

Balmer said the company had reached an agreement with the Australian Workers’ Union, but had not heard from the Building Trades Group, who the CFMEU are part of, for eight weeks.

“At the end of the meeting [Bailey] asked if we could do one thing for him, and that was to advise him of the eve that agreement was to be lodged with Fair Work,” Balmer said.

“As we left I looked to Neil Scales, and with the sign of his hand, [he] crossed his chest – akin to a blessing.

“It really enforced to me that it was Minister Bailey who was signing off on this path forward. It was really obvious to me, it wasn’t Neil Scales giving me the blessing.”

The agreement was approved in July 2022, about a month before the QTRIP conference.

In his statement to the inquiry, Scales said he believed the union was behind his contract not to being extended the following August.

In the written statement, Scales, who now lives in the UK, recounted intense meetings with Ravbar and Ingham to discuss the government’s workplace entitlement conditions created by the union, known as Best Practice Industry Conditions (BPIC).

He said was against BPIC, and the negotiations felt like “trench warfare” and he was not supported by ministerial staff when the union leaders would attack him verbally.

Scales said the meetings would regularly start with Ravbar going on a “tirade” about him.

“Mr Ravbar often remarked, ‘I’ve been talking to the f---ing premier and your minister and they all agree you are the worst f---ing DG ever,’” Scales said.

Brett Reed from the then-premier Annastacia Palaszczuk’s office, and Tam van Alphen from Bailey’s, were often in the meetings, Scales said, and would offer little support.

“I recall a meeting where Mr Reed said to me ‘Be quiet DG’. I was feeling very angry at the time and so I did go quiet in an attempt to calm myself and avoid making matters worse,” he said.

Eventually, Scales said he stopped attending meetings with the union as his presence would rile them up.

After his contract ended, the official union Twitter account posted: “Vale Neil Scales … Don’t let the door bang you on the arse on the way out.”

In the final session of the day a project manager from civil construction company John Holland laid out his view of BPIC’s effect.

Glynn Ladbrooke, who managed the Gold Coast Light Rail project between Burleigh and Broadbeach, told the inquiry the project’s price stood to go up by more than $428 million when BPIC was applied, much higher than the original estimation it would go up by $150 million.

He said the government had estimated the costs went up between 26 and 39 per cent, but the company’s number put the jump at nearly 66 per cent of the original $660 million budget.

“That’s the biggest I’ve seen so far, unless I’ve missed something,” commissioner Stuart Wood said.

However, he noted without knowing the amount the government ended up paying John Holland, it was difficult to know how much weight to give it.

“You shouldn’t just judge it because it’s an inch thick, it doesn’t necessarily mean it’s right, but does look like it’s the most comprehensive assessment of the impact of BPIC,” Wood said.

In his cross-examination, Chris O’Grady KC, who represented the union’s administration, questioned the company’s number, based on the fact the government did not reimburse the entire claim in 2024.

Ladbrooke said the company lost money on the project.

The inquiry will resume in Brisbane on July 28.

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