Attorney-General Chris Finlayson had no option but to yield to Labour and Act demands for select committee hearings, which resulted in changes including dropping retrospectivity with respect to pending trials, a clause explicitly upholding the protection of the Bill of Rights, and a timeframe of six months instead of 12 months.
The bill retains the provision where past convictions cannot be challenged on the basis of the Supreme Court decision.
Yesterday Mr Finlayson praised all parties for the passing of the bill.
"It's not a victory for any one political party. It is a bill that is a product of this Parliament and a credit to this House."
But Labour's Charles Chauvel said the changes to the bill may never have happened if the Government had the "blank cheque" it had asked for.
"I want to pay significantly more tribute to the Act Party for remembering its traditions in protecting civil liberties," Mr Chauvel said. "I hope that with Mr Banks and Dr Brash ... that tradition is not in significant danger."
Labour's David Parker said the party would have liked to have stronger protections including more judicial oversight for granting a warrant, and only granting them for investigating the most serious crimes.
"However we do accept that prospective power is needed for the police."
Green MP Keith Locke said people convicted on evidence obtained from hidden cameras should have the right to appeal.
"It is a fundamental principle of law that people engaged in court proceedings have the right to access the law as it was at the time of the alleged offence."
He said the Greens were in favour of hidden cameras, but not on private property.
"This is a step too far and not justified by the perhaps one or two extra criminals it might catch."
The bill passed with the Green, Mana and Maori parties opposing.