Special powers allowing the NSW corruption watchdog to handle illegal tapes are not exceptional because other state bodies already enjoy the same privileges, Premier Chris Minns says.
The Independent Commission Against Corruption (ICAC) was controversially granted the exemption to surveillance laws after obtaining what appeared to be recordings of private conversations made by a third party.
The recordings were uncovered during an investigation into the alleged stacking of a Liberal-held Sydney council in order to influence planning decisions linked to fugitive developer Jean Nassif.
The coalition is set to back a cross bench motion to revoke the powers when parliament returns in mid-September.
A disallowance motion only needs a simple majority in one house, most likely the 42-member upper house where Labor holds 15 seats.
"We respect it is parliament's obligation to review those powers," Mr Minns told reporters on Monday.
"But I think we've made the right decision."
Critics have pointed out that the extraordinary powers last until late 2025 and can apply to investigations other than the council probe.
Mr Minns said the alternative option was restricting the powers to the Liberal-linked investigation and being accused of making a politically minded decision.
The premier and attorney-general have both been briefed on the Nassif investigation but have declined to reveal what they were told in those meetings.
The powers were announced in parliament last week but will not take effect until November to allow parliament the time to conduct a review.
While unprecedented for the NSW ICAC, the premier said similar powers were already in place for corruption watchdogs in Western Australia, Victoria and the Northern Territory.
"So they're not extraordinary powers in the context of corruption-fighting bodies interstate," Mr Minns said.
The opposition has slammed the legal changes as a reckless power grab that was being pushed through without proper parliamentary debate.
Liberal leader Mark Speakman said the coalition would not support giving ICAC "open slather" to use any illegal recordings it obtained for a period of more than two years.
In a statement to AAP, the anti-corruption body said it had not reviewed the material closely and sought a legislative amendment to avoid any doubt about the legality of holding onto the tape.
"The commission considers it has acted appropriately and in accordance with relevant legal requirements," a spokeswoman said.
ICAC also alerted its own watchdog, the ICAC inspector, before approaching the government on August 9 for the powers, she said.
