Justice Timothy Brewer said he had not doubt Robertson would reoffend if released from prison.
"Your history makes it very plain you would be very likely to commit another qualifying offence no matter how long any finite sentence might be," he said.
The Gotingco family has released a statement saying they are extremely relieved this "cowardly and evil offender" has now been sentenced and the public can be kept safe.
In a statement read out by a family friend Alan Wharerau they said:
"While no sentence can ever return Blessie to us we are thankful this part of the legal process is completed and we can now focus on our family once again.
"We are forever hopeful that now this sentence has been passed down, Robertson will never walk the streets again. Blessie's death was totally preventable and highlights that the current New Zealand system does not effectively monitor high-risk offenders. Offenders like him should not be released given their extreme risk . . . Blessie paid for this with her life
"There are other Robertsons living within our communities and the family is hopeful the independent review's scope will ensure that their monitoring capabilities and processes of the Corrections department are reviewed and corrected urgently. Blessie's death must not be in vain."
Reports by mental health professionals highlighted Robertson's propensity for violence and lack of empathy for his victims, especially since he continued to deny the offending.
He "opportunistically uses manipulation and intimidation to have his needs met", one said.
In court today, her husband Antonio Gotingco spoke of the "pain and torturous anguish" the slaying had caused.
"We've been robbed of the very essence of our lives," he said.
The "unbelievably violent, cruel, depraved and vicious attack that ultimately ended her life" had similarly impacted Ms Gotingco's children.
"Whenever I close my eyes, I'm unable to think of anything else," her eldest son John Gotingco said.
"My faith in the system has been irreparably broken."
On May 24 last year, Robertson - who spent today's sentencing with his head bowed, surrounded by security staff - hit Ms Gotingco while she was walking home down a Birkdale street.
Seeing her motionless body on the road, Robertson scooped her up, bundled her into the back of his BMW and took her to his nearby apartment just in time to make his curfew.
The court heard he was being monitored by Corrections via a GPS anklet at the time.
Once he was in the garage, beneath his home, the defendant sexually abused the injured woman before strangling her, stabbing her and slashing her throat.
Early the following morning, he wrapped Ms Gotingco's body in a bed sheet and took her to Eskdale cemetery down the road where he dumped her body in thick bush.
Despite Robertson's claims the initial collision on the street was an accident Justice Timothy Brewer said his subsequent actions totally contradicted that.
Robertson had name suppression throughout the trial and for some time afterwards, as he appealed the court's decision to cease the order.
However, last week the Supreme Court ended the string of appeals and the defendant's dark past was revealed.
In December 2005, Robertson kidnapped and molested a 5-year-old girl and attempted to abduct two other children in Tauranga. He served almost eight years in jail and was released in December 2013.
Justice Brewer said the case had strong similarities to his most recent offending.
Ms Gotingco's son John said he hoped her death was "not in vain" and that measures would be put in place to stop a similar incident.
And last week Corrections Minister Peseta Sam Lotu-Iiga announced an independent review would be carried out of Corrections' monitoring of Robertson following his release from prison.
TIMELINE
2005: Tony Robertson is convicted of several offences, the most significant relating to the abducation and molestation of a 5-year-old girl.
2006: An 8-year sentence is imposed against Robertson, who began the year in custody hitting a prison guard over the head with an electric fan.
2008: Robertson's final appeal to the Supreme Court over his conviction fails.
2013 December: At the end of an 8-year sentence, Robertson is released under strict conditions imposed by the Parole Board including wearing a GPS tracker.
2014 January: Robertson is convicted of his first breach of release conditions and arrested on his second breach.
2014 February: Department of Corrections successfully seeks an Extended Supervision Order, requiring Robertson to wear a GPS tracker for 10 years, among other conditions.
2014 March: Police check Robertson's GPS movements and clear him during an inquiry into a potentially indecent approach to a child near his home.
2014 May: Blessie Gotingco goes missing walking home from the bus stop near her home. Robertson is arrested and charged with her murder.
2015 May: Robertson is convicted of the murder and rape of Mrs Gotingco.
2015 July: Name suppression is lifted.
