Karauria was found critically injured with stab wounds in Onekawa on Alexander Avenue in the early hours of Sunday, 11 May, and died at the scene.
Police are yet to arrest anybody for the killing.
But a teenage girl was taken into custody on Monday, after police investigating Kaea's death learned that a witness had been approached and allegedly threatened.
Detective Inspector Dave de Lange said the alleged incident occurred on May 12, a day after the teenager was killed.
He said the teen has been charged with wilfully attempting to pervert the course of justice, and will reappear in the Hastings Youth Court next month.
Detective Inspector de Lange said police treated any form of witness tampering seriously.
"When a witness is threatened, or attempts are made to sabotage an investigation, police will act without hesitation. This should be a warning to anyone who contemplates interfering with justice."
He said anybody with information about the incident needed to contact police.
"Kaea deserves justice, as does his family, so if you can help please talk to us," he said.
