The CFMEU and one of its officials accused of unlawfully climbing a crane and hindering work at a construction site are facing legal action brought by the workplace watchdog.
The Fair Work Ombudsman says Stephen Parker exercised his right-of-entry permit at a 19-storey office tower Multiplex site in Perth in November before breaching the Fair Work Act.
It alleged Mr Parker climbed the tower crane's 50-metre ladder to the cabin where he remained for about an hour, stopping it from operating.
Mr Parker is also accused of obstructing the site manager from restarting the crane generator after demanding a pre-start check demonstration and maintenance work.
The ombudsman alleged the generator and crane were inoperable for about two hours, creating a safety risk for workers relying on the crane to lift a rescue cage in an emergency.
Mr Parker and the Construction, Forestry and Maritime Employees Union are accused of breaching section 500 of the Fair Work Act, which prohibits acting in an improper manner or intentionally hindering or obstructing persons at a work site, twice.
They also allegedly twice breached section 499 of the act, which requires right-of-entry permit holders to comply with occupational health and safety requirements at work sites.
If found guilty Mr Parker could be fined up to $18,780 per breach and the CFMEU faces penalties of up to $93,900 per breach.
Acting Fair Work Ombudsman Michael Campbell said the union had an extensive history of non-compliance and the regulator was taking legal action to deter further unlawful conduct.
"Union officials are provided rights under industrial laws, which can include certain rights to enter work sites, but they come with related legal obligations to behave in a proper manner and meet health and safety requirements," he said in a statement on Thursday.
A directions hearing is scheduled in the Federal Court in Perth for November 29.
The CFMEU said it would not comment on the allegations before the court.
"However, our organisers prioritise safety at all times, and it should be noted that this matter is being brought in the day following yet another tragic death of a construction worker," a spokesman said.
The Fair Work Ombudsman has secured total penalties of more than $3 million against the CFMEU and its officials in court cases since December 2022.