Former CFMEU boss John Setka will not face police charges after appearing at two Victorian construction sites this week.
Victorian Premier Jacinta Allan referred the matter to police after video emerged of Mr Setka delivering a speech to workers at the Footscray Hospital site and reports that he attended Metro Tunnel construction sites.
Ms Allan described Mr Setka's presence at the workplaces as unacceptable and unlawful.
On Friday, Victoria Police today said it had completed its assessment and had not detected any criminal offences.
"For there to be a trespass offence, a person must be asked to leave by someone in charge of the site or who has authority at the site," a Victoria Police spokesperson said.
"The person then has to refuse to leave within a reasonable time.
"There is no evidence that this occurred on Wednesday or Thursday, therefore there has been no trespass offence committed."
It said no further action would be taken by police.
On Thursday the Fair Work Ombudsman said it was investigating whether federal laws had been breached by Mr Setka's attendance at the site.
Police assessed numerous allegations involving the union raised in the media. (Graeme Powell)
Victoria's Transport Infrastructure Minister Danny Pearson issued a further warning to Mr Setka to stay off government worksites, saying he was no longer an elected official and was not authorised to be there.
"He's just like any other member of the public," Mr Pearson said.
"He has no right to be on these sites and it's my expectation that if John Setka, or any other member of the public seeks to access a Big Build site in an unlawful manner, the police will be called."
Mr Setka resigned as Victorian CFMEU secretary in July following allegations of misconduct within the union reported by Nine newspapers.
The construction division was placed into administration by the federal government last month.
Ms Allan earlier this week said the director general has spoken to contractors building large infrastructure projects in Victoria and reminded them that only authorised people are allowed onsite.
Meanwhile, detectives from the Financial Crime Squad have finished their assessment into 20 other allegations of potential criminal activity involving the CFMEU.
The police spokesperson said eight matters were deemed to be in the remit of Victoria Police.
They said charges were being considered in relation to fraud within the building industry.
Investigations continued into alleged intimidation of a developer.
A man had been charged over a separate allegation of threats to assault two owners of a labour-hire company.
They said no further action would be taken in five other matters.