The Barr government has managed to get its reforms to compulsory third party insurance over the line - but the promised savings have largely eroded through the process.
A no-fault system of motor vehicle accident insurance will begin in the ACT on February 1, 2020, after the legislation finally passed late on Thursday.
Under the changes, anyone hurt on Canberra's roads will be able to receive treatment, care and lost income benefits for up to five years whether or not they were at fault, with those who are more seriously injured able to sue for a capped level of compensation through the common law system.
Its passage marks the end of a long road for reform of the ACT's no-fault, common law scheme , after a failed attempt in 2012, a citizen's jury in 2017-18 and a Legislative Assembly inquiry.
It came in the face of a sustained campaign against the changes from the legal fraternity, concerned not-at-fault motorists would have their compensation constrained in order to extend it to at-fault drivers.
ACT Opposition leader Alistair Coe described it as a "dark day for all motor vehicle accident victims in the ACT" and many "unintended consequences" would follow.
However Chief Minister Andrew Barr said the reform was "long overdue" and "Canberra motorists will benefit".
Greens crossbencher Caroline Le Couteur said she had "no doubt" there would be issues with the legislation, which would be looked at as part of a review in three years.
But most of the savings promised by the new scheme will not materialise due to changes required to get the Greens support for the legislation.
Originally premiums for the scheme were modelled at $385 and $465 - a saving of between $91 and $171 on 2017 levels.
But the expected premiums rose in March, after the Greens succeeded in getting Labor to extend the ability to sue for common law damages to children and injured workers who do not meet the 10 per cent whole of person impairment threshold.
As a result the savings deteriorated to between $14 and $99.
But motorists could now save as little as $8 on new scheme after further changes required by the Greens to get the reforms over the line.
On Tuesday, Labor agreed to a Greens amendment to allow injured Canberrans who earn less than $50,000 per year to access payments equivalent to superannuation.
Superannuation payments were not included in the original legislation due to technical issues that will require a change to Commonwealth law.
An ACT government spokeswoman confirmed the Greens amendment lowered expected savings by a further $6-10 as a result of the last minute changes.
That means the expected savings of the scheme are now $8 and $89.
The government spokeswoman said those figures were only indicative and final premiums for the new scheme will be determined once the legislation has passed and insurers make their premium filings to the Motor Accident Injuries Commission for approval.
Mr Barr said while there had been "trade-offs, he still expected premiums to fall because of the reforms while increasing coverage for motor vehicle accident victims.
"It is redistribution of the scheme's resources away from legal fees into medical fees, rehabilitation and more support for ... victims," Mr Barr said.