Family and friends held a candlelit vigil at the time and place of Rangimaria's death this week, but White and Davis didn't attend as they were not ready to return to the place their happy, bubbly daughter's life was tragically cut short.
"There's no moving on until we know exactly what happened to her," Davis said.
"I still hope the person responsible, or people who know who is responsible, will feel guilt and provide police with enough evidence for them to lay charges."
Living without closure is not the only source of anguish for White and Davis.
They believe several people could have helped prevent their daughter's death.
The couple, who moved to the rural settlement of Waiohau, 30 minutes south of Edgecumbe, six months before Rangimaria's death, went away for the night of July 25 last year.
Rangimaria asked to stay with a friend in Opotiki. She told her parents they would be staying in and watching movies.
But Rangimaria was drinking that night. White and Davis only found out when told by police the day after her funeral.
The drinks were bought by Roberta Kingi, 42, a friend of a friend. Kingi, who purchased a box of vodka pre-mixed drinks, was fined $600 in November last year for supplying alcohol to a minor.
There's no moving on until we know exactly what happened to her.
The night she died, Rangimaria and a friend tried to attend an Opotiki College after-ball function but were turned away by parental security. About 3.30am on July 26, Rangimaria collapsed on Goring St.
Her friend was unable to move her so she yelled for help. No one answered.
She knocked and cried out for help at a few neighbouring properties, but no one responded.
Panicked, the friend ran to her home to get help. Rangimaria was struck as she lay in the road and the car sped away.
"If I'd known Rangimaria would have been able to go off drinking from her friend's, I wouldn't have let her stay there," Davis said.
"If I'd found out on the night that she was drinking and trying to get into a party, she would have been in a world of trouble, but she would have been alive.
"Rangimaria was a top student. She had never drunk in her life. She had absolutely no idea how to handle alcohol."
Davis was thankful the girls were turned away from the after-ball event but "quite disgusted" adults didn't ensure they got home.
Residents of one of the neighbouring properties later admitted hearing Rangimaria's friend knocking and yelling for help.
Davis found it "pretty gutting" they did nothing. White added: "If something can come from this tragedy, I hope it's that people will be held to account for supplying alcohol to children."
• Anyone with information about the hit and run is asked to contact their local police station, or Crimestoppers anonymously on 0800 555 111