The construction union's Victorian branch has ramped up its fight against Labor leader Anthony Albanese's push to oust John Setka, passing resolutions which draw out its battle lines.
The resolutions include unconditionally supporting Mr Setka, the secretary of the Victorian branch of the CFMMEU, and calling the union's national office to do the same.
It also wants the national tier to decry and forensically investigate the "cowardly manufactured leaks" from the most recent national executive meeting.
Mr Setka has been accused of telling colleagues at that meeting that anti-family violence campaigner Rosie Batty's advocacy had led to men having fewer rights.
But the union is digging in behind its leader, vowing to appoint an independent investigator to check the phone records of those who attended the meeting.
The resolutions also include a vow to cease all financial support to the ALP if Mr Setka is expelled from the party, and to cut ties with unions that have "attacked the branch".
Labor has received at least $11 million in donations from the CFMMEU nationally since 2000.
Labor leader Anthony Albanese appears unfazed by the possibility of losing money from the union, saying he makes decisions based on their merits and not from a funding perspective.
"I'm pro-union, but I'm also pro-making sure that union officials bring credit to the trade union movement," he told ABC News.
Mr Setka said Labor had squandered millions of dollars during its unsuccessful federal election campaign.
He vowed a long battle if Mr Albanese tries to expel him from the party.
"I am a little bit old school, I actually think you should have actually done something before you get cooked on a spit about it," he told the New Daily on Monday.
"The bottom line is I am for fair play. They've accused me of bagging Rosie Batty. Now, it's clear that wasn't said. Well, good luck to them. It's going to be a long, drawn-out thing."
Mr Setka is facing court later in June when he is expected to plead guilty to two criminal charges, including one of using a carriage service to harass a woman.
Mr Albanese said the party had received legal advice, which it acted upon, in terms of first suspending Mr Setka's membership before the expulsion process took its course.
"Mr Setka is entitled to defend his position," Mr Albanese told Sky News on Monday.
"But the Labor Party as an organisation is entitled to determine who joins us, what our membership is, like any other organisation, and it is very clear that the national executive has complete power to determine membership issues."
He said past challenges to the party's ability to decide on membership matters had failed in the courts.
It is understood there is a six-month time limit on most complaints under ALP rules so evidence relating to Mr Setka's activities beyond this timeframe may not formally be arguable.
ACTU secretary Sally McManus last week demanded Mr Setka resign as secretary of the Victorian CFMMEU with the leaders of the three largest unions - representing mainly female workforces - following suit.
The Australian Workers Union on Sunday backed the other unions, but called for proper processes to be followed.
Australian Associated Press