Aaron Rhys McDonald, 38, pleaded guilty to murdering Farrall at his second court appearance, via audio visual link (AVL), in the High Court at Christchurch this morning.
He also lost his name suppression and his identity can be revealed for the first time.
The body of Miss Farrall, 24, was found in the boot of her car at a Woolston supermarket on the morning of March 29.
This morning, some of her devastated family members were in court to see McDonald on the AVL screen wearing green prison clothes and with a slight smirk, he said, "guilty your honour" to charges that he raped and killed her.
He also pleaded guilty to causing grievous bodily harm to Ms Honda by pushing her out of a moving vehicle, and also causing grievous bodily harm to Ms Brandl.
A minor charge of operating a motor vehicle recklessly as he tried to evade police before being arrested after a five-hour stand-off, was also admitted.
He had been sentenced at Palmerston North District Court in May 2009 to five years and three months in custody for multiple crimes, including the manufacture of methamphetamine, burglary, theft, and arson.
A hearing at Rimutaka Prison last September was told McDonald was a self-confessed alcohol and methamphetamine user who smoked cannabis daily since he was 15 but his risk to the community over the remaining nine months of his sentence could be "adequately mitigated".
He told the board that he had accommodation available in Christchurch.
"There is, however, no work available there, although he has tentatively proposed that in time he may work with a friend in Christchurch. This seems to be some way off at the moment," the decision said.
Special conditions attached to his parole, imposed until December this year, included that he attend a medium intensity relapse programme, undertake an alcohol and drug treatment, or counselling, programme, and to live at the nominated address.
He was on a 10pm to 6am curfew for the first three months of his release and was banned from drinking alcohol or taking illicit drugs or synthetic cannabis.
Crown prosecutor Christopher Lange said a police summary of facts from the murder trial has not yet been finalised.
Mr Lange asked for two health assessors' reports to be carried out on McDonald, a kitchenhand from Otaki, which could see him sentenced to an open-ended period of preventive detention.
Defence counsel Elizabeth Bulger said she was not seeking a continuation of an interim name suppression order made at McDonald's first court appearance, made at his Christchurch Hospital bedside where he was undergoing surgery for police dog bites sustained during his arrest.
Justice Graham Panckhurst called for reports ahead of McDonald being sentenced at the High Court in Christchurch on May 29.
