On the same day as the Business Council of Australia has called for cuts to the minimum wage, the Coalition has revisited its politically-motivated policy attacking unions' ability to represent workers' interests, the ACTU said.
The ACTU has no tolerance for corruption by union officials, said ACTU Secretary Dave Oliver.
"There's support across the movement for strong penalties for those that break the law and that's why we supported a tripling of the Fair Act penalties in 2012," said Mr Oliver.
However, criminal activity like misappropriating members' money is a far cry from the kind of governance breaches for which Tony Abbott is proposing harsh fines, he said.
"Australian unions are fully committed to high levels of transparency and accountability within the movement, but the Coalition's proposals are just gratuitous political attacks," said Mr Oliver.
"The Coalition is proposing harsh fines for failing to file paperwork on time. We don't accept that unions should face the same financial penalties around these sorts of governance issues as multinational corporations, which turn over billions of dollars each year.
"The Coalition also restated its commitment to re-establishing the Australian Building and Construction Commission that wasted millions of dollars prosecuting building workers for simply exercising their rights to join a union."
Opposition Leader Tony Abbott has 'announced' his package of fines and penalties for trade union officials several times now, said Mr Oliver.
"Most Australians will see this for what it is, a politically-motivated attack on unions," he said.
"On the day the Business Council of Australia attacks the minimum wage, which would affect 1.2 million workers, Mr Abbott fails to mention wages and instead attacks unions.
"It appears business is going to attack pay and conditions while the Coalition works at tying up unions with politically-motivated regulations and harsh penalties.
"Australian workers should be very concerned about the future of their conditions at work.
"With business campaigning hard for cuts to wages, penalty rates and job security, Australian workers need unions that are able to do their job more than ever."
Contact: Ben Ruse 0409 510 879 or Eleni Hale 0418 793 885