The teen, who has interim name suppression, is on trial in the High Court at Dunedin defending a charge of murder.
He says he was acting in self-defence when he fatally stabbed Enere Taana-Mclaren, 16, who went to a different school and was unknown to him.
Yesterday, Justice Robert Osborne and the jury heard evidence from the detective who analysed the defendant’s Chromebook.
Earlier on May 23, the day of the fatal stabbing, the defendant was held in a school office for about an hour after he had been identified as part of a group of students allegedly vaping in the toilets.
Detective Constable Keith Early said that on that day the defendant messaged his friend from his Chromebook about setting up a fight with a "snitch" from his school.
The fight did not happen.
"Did that fella snitched [sic] on you for vaping?" the friend asked.
"Basically even though I wasn’t," the defendant replied.
He sent messages to the friend about wanting to fight the person who "snitched".
"He told the principal, imma f... him up," the defendant said.
"Should come South D then we can f... up this c... G."
His friend suggested they should record the "scrap".
About a month earlier, he told the same friend about another incident at the bus hub.
"I was walking past the bus hub and he tried stepping me out but I had my knife so yeah," the message read.
"Don’t let no-one step you out G," the friend replied.
A schoolgirl told the jury about how she saw the conflict unfold.
Enere making a comment about the defendant’s outfit was what first caught her attention.
The two were talking and they moved on to the road, she said.
"I saw [Enere] rolling up his sleeves like they were gonna fight."
Her view was partly obstructed, but she heard "a loud slap sound".
In her statement to police, she said Enere was "walking like a duck" with his feet turned outwards and taking deliberate steps.
Counsel Anne Stevens, KC, asked the witness "did you see that way of walking as a bit threatening?".
The witness said it was.
Enere said words like "come on, wanna go", but the defendant "didn’t want to get involved", she said.
He was backing away and his hands were down by his side.
She went to Countdown to get away from the situation.
When she came back, she saw Enere with his hands on his head, looking "really worried".
Another witness, Michael King, heard Enere make a comment about the defendant’s socks before yelling "don’t you remember when I knocked you out?".
He recalled Enere saying "pull it out man, pull it out then".
"And then a knife appeared."
The pair began fighting and the defendant was "wildly swinging the knife" and the scuffle moved into the road.
"[Enere’s] arms were up, and he was moving backwards and forward ... trying to dodge it," Mr King said.
The pair were pulled apart and he saw Enere lift up his shirt, revealing a wound.
The trial is set down for 18 days.
felicity.dear@odt.co.nz , Court reporter
