A fledgling Kiwi rapper and stepbrother of former Cabinet minister Nikki Kaye is appealing his conviction for a United States jailhouse murder all the way to the Californian Supreme Court.
Former Auckland Grammar student Clinton Forbel Thinn is serving 25 years in prison for killing his San Diego cellmate Lyle Woodward in December 2016.
And despite not taking the stand his own defence, Thinn claims an abuse of his constitutional rights and says he is not a murderer.
Thinn, who had been awaiting trial for an armed bank robbery, strangled Woodward to death over several minutes using a ripped cloth ligature.
He immediately called for help and was found standing over Woodward, red-faced and breathing heavily with a "1000-yard stare".
Thinn, the son of prominent Auckland lawyer Neil Thinn, had attended rehab for drug and mental health problems before travelling to the US to pursue a rap career.
There are now questions about how he was able to travel overseas given his addiction problems and previous drug and firearms convictions after he was caught in downtown Auckland carrying a loaded semi-automatic rifle and 40 rounds of live ammunition.
Thinn, who orginially faced the death penalty, was convicted of first degree murder in July 2018 after an earlier trial resulted in a hung jury.
He appealed the conviction in July this year. Thinn's lawyer Robert Boyce argued the killing was self-defence, and the trial judge had erred by ruling crucial defence evidence inadmissible.
The evidence related to Thinn's state of mind at the time of the attack, as well as testimony from experts and former inmates about racial tensions and politics in US prisons.
The evidence, which had been allowed at the first trial, was designed to show Thinn was isolated and vulnerable as a white foreigner locked in a cell with two black inmates.
It was argued that Thinn had been bullied by Woodward, who stole the New Zealander's food. Due to his nationality and accent, Thinn was especially vulnerable to violence and had a greater need to stand up for himself, the court had heard.
The appeal was thrown out. The judges ruled the evidence was at best "speculative" about what had occurred and did not prove Thinn was fearing for his life when he killed Woodward.
"Although various things COULD have happened in the cell, racial dynamics only supported a speculative inference as to what actually happened unless there was something more to suggest that Lyle attacked Thinn in the cell because of his race."
However court documents filed by Boyce in the Californian Supreme Court seek a review of the appeal decision, claiming an abuse of Thinn's constitutional rights.
Boyce argues the decision to exclude vital and relevant evidence about prison culture and Thinn's vulnerability undermined the defence case and his right to due process.
He also argued the jury should have been instructed about self-defence before being sent to deliberate - as the jury was in the first trial when a majority did not convict Thinn of first degree murder.
"Although most of Thinn's evidence about his vulnerability in the jail was excluded, there was still evidence he acted in self-defence: he had red marks on his body suggesting a physical struggle, he called for help for the victim, suggesting he had not initiated an attack intended to kill the victim, and a deputy from the jail testified the jail was generally segregated by race and it was unusual that Thinn was a white inmate in a cell with two black inmates."
Boyce cited CCTV footage showing Thinn not exiting his cell for breakfast until everyone else was finished, indicating his isolation.
The defence also argued Woodward smoked methamphetamine before the attack. That, combined with red marks found on Thinn's body, was enough to suggest Woodward had attacked Thinn, who had then killed his cellmate in self-defence.
Excluding "contextual" evidence about prison culture and Thinn's vulnerability destroyed his constitutional right to present all relevant evidence to the jury, Boyce said.
"Trial judges in criminal cases should give a defendant the benefit of any reasonable doubt when passing on the admissibility of evidence as well as in determining its weight," his submission stated.
The "People" had the burden of proving beyond reasonable doubt that the killing was unjustified.
"The cumulative effect of the errors deprived Thinn of due process," rendering Thinn's conviction unfair.
The Supreme Court is now considering Thinn's application.
Thinn's father declined to comment on the case this year and Kaye told the Herald she did not wish to comment while the appeal process was under way.
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