Acting Judge Bert Bam said on Friday he would start the judgment in the lengthy trial on Monday morning.
He intended completing his judgment even if it meant extending court hours.
Kotze, Andries Sithole, Pieta Mohlane and Sello Mphaka are on trial for allegedly murdering Kotze's stepson Conrad Bonnette (19) and kidnapping, repeatedly raping, and attempting to murder Kotze's former wife Ina Bonnette in his Modimolle, Limpopo, home on January 3 2012.
Kotze has denied guilt, claiming he could not be held accountable for his actions that day.
A defence psychologist testified that Kotze had a narcissistic personality disorder and suffered from an acute stress disorder and major depression, which resulted in a state of dissociation during the incident.
However, a psychologist testified for the state that Kotze did not suffer from any mental disorders and could be held accountable for his actions.
Sithole, Mohlane, and Mphaka claimed Kotze had threatened to shoot them if they did not co-operate.
They said they pretended to rape Bonnette because they could not get erections.
Testified
Bonnette testified that the three men looked on while Kotze sexually tortured her and mutilated her breasts, then took turns raping her.
She was still tied to a bed with tape over her mouth when she heard her son repeatedly say "Please uncle, don't shoot", followed by three shots.
He died at the scene after being shot in the face, chest, and knee.
Bonnette had to undergo reconstructive surgery and was put on antiretroviral treatment after it emerged that Sithole had tested positive for HIV following his arrest.
Prosecutor Retha Meintjes argued that all the accused were guilty of attempting to murder Bonnette because of Sithole's HIV status.
'Russian roulette'
Sithole's advocate Jan van Rooyen, and Francois van As, for Mohlane and Mphaka, argued that their clients had not been aware of Sithole's or their own HIV status, and could not be convicted of attempted murder.
Van As argued that his clients had "played Russian roulette" because they did not know each other or the victim's HIV status.
Bam remarked that he had not heard of a rapist who first asked his victim if she had Aids. Van As said his clients were just as traumatised as Bonnette because Kotze had threatened to kill them.
He argued that the absence of DNA evidence supported his clients' version that they had not raped Bonnette. The absence of any physical injuries to Bonnette also supported this.
"Their intention was not to go there and rape her. They were there against their will. There is ample evidence to support their version that they were threatened," he said.
Piet Greyling, for Kotze, said the court should accept Kotze's version that the other three acted on their own and that Kotze had not threatened them with a firearm.
"He was angry with her. It was coincidence that they became co-perpetrators," Greyling said. – Sapa