Leota punched a prison guard on April 19, 2011 in Mt Eden Prison after becoming "abusive and obstructive" while being strip searched for a court hearing.
The punch broke the officer's jaw in two places and after two years of corrective surgery it was reported he would never return to work.
Leota was convicted of wounding the guard with intent to injure following a jury trial that took jurors three hours of deliberations before returning with a unanimous guilty verdict.
At the time the Crown considered a preventative detention sentence but he was ultimately jailed for nine years.
Addressing Judge Roy Wade in an Auckland District Court appearance in July 2013 Crown prosecutor Michael Walker said "Leota's adult life is littered with violent offending".
"It is clear that with Mr Leota, custodial sentences don't work with him and he continues to offend inside and outside of prison.''
Shortly after this he attacked a prison officer in Hawke's Bay and was later sentenced to more time in jail.
At the time of the beating Poi was three months into serving a three year sentence for a vicious attack where he had repeatedly bashed the back of a man's head with a bottle.
He was described by Crown prosecutor Steve Manning as a "pretty green" prisoner who had found himself in the company of experienced prisoners.
Poi had been part of an arrangement to smuggle contraband, namely drugs and tobacco, into prison during a family visiting day. Samoa and Leota's partners had couriered the contraband to Poi's partner to bring in with a friend during a visit on March 21 2015.
The drugs were instead thrown out the car window after the two women saw cars being searched as they approached the prison.
CCTV footage played during the trial showed Leota leading Poi into his cell just minutes after the family event had finished.
Just after, a convicted murderer whose name is suppressed assisted Poi who was laying unconscious in a pool of blood, and took him to the guard house to get help.
During inquiries into the assault on Poi his lawyer said it would take "somebody to break ranks and talk before they get a prosecution."
In his closing statement on Thursday Manning told the jury "it took guts" for the witness to come forward and testify.
"You don't have to like him but you have to admire his fortitude. It took courage and it took character, not words you would normally associate with someone who is in prison for murder."
Leota was remanded for sentence scheduled for the end of June.