Criminal investigations have been launched into fraud within the building industry and intimidation of a developer, with Victorian police finalising inquiries into 20 allegations against the CFMEU.
Police also confirmed on Friday former construction union boss John Setka won't face criminal charges over visits to government work sites, despite begin referred to them by Premier Jacinta Allan.
Victoria Police looked into 20 allegations of "potential criminal activity" following weeks of media reporting on the CFMEU.
Eight have been deemed to be within the remit of the force, with three matters currently under investigation, a spokeswoman confirmed.
Police said charges were being considered and assessed by external lawyers as part of a "complex investigation" into allegations of fraud within the construction sector.
A separate investigation into alleged intimidation of a developer remains ongoing but no criminal offence has been identified to date, with the case to be finalised within two weeks.
A Beveridge man, 40, understood to be a CFMEU organiser, has been charged with threatening to kill and inflict serious injury against two owners of a labour hire company.
No further action will be taken over five other allegations assessed by detectives for various reasons including that people involved were unwilling to make statements or a lack of criminality identified.
A dozen more allegations were found to be outside the remit of police and will be examined by the Fair Work Commission, Fair Work Ombudsman, federal police, tax officials or other agencies.
Victoria Police also confirmed Mr Setka won't face criminal charges after gaining access to two government building sites to address workers earlier in the week.
Senior Victorian minister Danny Pearson said there was no place for violence or bullying on any site but did not go into details.
"Every Victorian worker deserves to work in a professional, safe environment," he told reporters in Melbourne on Friday.
"There's no place for violence on any worksite here in Victoria."
The CFMEU was placed into administration by the federal government following allegations of corruption and bikie infiltration, which sparked angry protests as thousands of tradies downed tools and walked off the job.
Four unions have pledged $1 million to the CFMEU's High Court challenge against the Albanese government's takeover, with its leadership claiming members were denied due process.
Asked about reports a group of left-wing unions were committing cash to back the CFMEU, ACTU president Michele O'Neil said the union movement wouldn't agree on everything all the time.
"We have seen that reporting and a number of unions have spoken to us about that, so I am aware of that," she told ABC's RN on Friday.
"We're a diverse movement and people have strong opinions but it is at its core about who we are and what we stand for and we don't walk away when things get tough, we face up to them.
"Angry individuals lashing out and blaming everyone except themselves, doesn't get us through this."
Meanwhile, the Communications, Electrical and Plumbing Union voted to disaffiliate from the ACTU on Thursday, over the peak body's support for the forced takeover of the CFMEU.