Senate powerbroker Jacqui Lambie is threatening to vote against all government legislation if it persists with a "toothless" integrity commission.
Senator Lambie has reaffirmed an earlier warning to tell the coalition "where to stick their bills" unless they establish a powerful anti-corruption watchdog.
"It had better get a hell of a lot better than what it is right now," she told ABC radio on Wednesday.
Senator Lambie has previously demanded a federal integrity commission with more teeth than Jaws, describing the government's proposed model as a "lap dog with dentures".
"You're better off not having one at all," she said.
"This is as weak as water."
Senator Lambie is particularly scathing of allowing public servants, politicians and their staff to give evidence in private.
"What makes them so special? Seriously."
She also wants broader referral powers for whistleblowers and members of the public, rather than just government agencies.
Both issues are addressed in an integrity commission model being proposed by independent MP Helen Haines.
"I suggest they go and have a good look at her bill and make sure that it looks pretty damn similar, as a matter of fact it should be identical, like twins," Senator Lambie said.
"When they've done that then I think you'll find the cross bench, Labor and the Greens will take them seriously."
Attorney-General Christian Porter said "terrible injustices" had been done to people through public hearings run by state integrity bodies.
"I think that it's wise to be cautious when you empower a body ... and give it more serious investigative powers than a royal commission has, that you actually require that body to put a brief of evidence together, to send it to the DPP and have the public hearing in a court," he told 6PR.
Universities will be subject to the commission under the draft laws, something that came as a shock to the sector.
"We are very surprised to see universities under the terms of the proposed Commonwealth Integrity Commission," Universities Australia chief executive Catriona Jackson said.
"We are taking this up at the highest levels."
The CIC could look at such matters as foreign interference in universities.
National security risks within universities will also be examined by the parliament's powerful intelligence and security committee, which has been asked by Home Affairs Minister Peter Dutton to conduct an inquiry to report in July next year.