Disgruntled CFMEU members are being asked to anonymously reveal their experiences of menacing or unlawful conduct as part of an inquiry into corruption within the union.
The CFMEU's construction arm was placed into administration after allegations of criminal conduct and organised crime links on job sites.
The Fair Work Commission tasked independent firm KordaMentha in August with auditing and preparing a report on the financial risks the union may face after it entered administration.
The firm has established an anonymous reporting website for anyone, including CFMEU members, wanting to report "corrupt, menacing, improper, unlawful or criminal conduct" by industry and union officials.
"This platform is designed to keep you safe by allowing you to report something with the option of anonymity," the platform said.
KordaMentha said it would complete a preliminary report by December 3.
The CFMEU faced heightened scrutiny after Nine Newspapers revealed allegations the construction and general division was involved in criminal and corrupt conduct.
Administrator Mark Irving promised detailed investigations to expose the grip outlaw motorcycle gangs and organised criminals had on the union's construction arm.
After receiving a damning report into the Victorian branch, which indicated it was laden with violence and intimidation, he committed to establishing an integrity unit.
The body will investigate a growing number of allegations and also scrutinise the relationships between suppliers and former senior union officials, particularly in Victoria.
Other branches in NSW, Queensland and South Australia will also be scrutinised over the extent of bikie and organised crime involvement within their construction industries.
