Worksite ban sparked union's legal warning to top cop

A union strongman wrote to a state's police commissioner accusing officers of unlawful behaviour after CFMEU members were refused entry to a worksite, an inquiry has been told.

A letter was shown on Tuesday to Queensland's long-running inquiry into the CFMEU in which ousted boss Michael Ravbar threatened top cop Steve Gollschewski with legal action.

In the letter dated May 10, 2024, Mr Ravbar accused police of "breaching, or coming perilously close to breaching" the Fair Work Act and the Work Health and Safety Act.

Mr Ravbar's complaint concerned an incident in which police moved on union members seeking entry to the Cross River Rail work site in the south Brisbane suburb of Dutton Park on May 3, 2024.

Mr Ravbar told the police commissioner the union was considering litigation regarding the alleged breaches.

He reminded Mr Gollschewski of Queensland Police's commitment to a memorandum of understanding with the workplace safety regulator, asserting it was "embedded" in its operational procedures manual.

The memo obliged officers to follow the advice of the Office of Industrial Relations in relation to any workplace entry matters.

The letter demanded Mr Gollschewski reaffirm in writing that Queensland Police remained committed to the MoU and that it would take steps to ensure that officers would comply with it.

Mr Ravbar told Mr Gollschewski that his response would have a "significant bearing" on the union's threat to pursue legal action against Queensland Police (QPS).

"Leaving to one side the debate about whether the QPS acted unlawfully on 3 May 2024, I am sure that we can agree the QPS acted inappropriately that day," he wrote.

A few days after the letter, CFMEU representatives blocked a truck from entering the $353 million Centenary Bridge upgrade project in Jindalee, in Brisbane's west.

Police directed the truck to leave in order to ease peak-hour congestion on the Centenary Motorway.

The incident prompted Commissioner Stuart Wood KC to rebuke police during the inquiry's previous block of hearings.

The bridge had become the focus of a CFMEU campaign against the joint contractors, BMD and Georgiou Group.