Police who searched Maney's house about two weeks after Rikihana's death described in evidence Maney appeared "frail" and "pretty decrepit". He was battling lung cancer at the time and died five months later.
Maney's letter, which was full of gang slogans and was addressed to his son, said Rikihana was tied down in the back of Jury's car and he was begging for his life.
Maney's letter said Rikihana had hit Jury in the face with a hammer. It went on to say: "F*** knows what [is] going to happen ... his own fault".
He said in the letter that you "couldn't do that to a mongrel that's been around forever", but he wanted "nothing to do with it".
Jury had turned up at his door with Rikihana tied up in the back asking "what to do", the letter said.
He described hearing Rikihana begging "please no more" as he was bashed.
Rotorua police Senior Sergeant Herby Ngawhika, who found the letter, told the court that the notepad had been sitting in front of Maney at the table and he had made no attempt to hide it.
Officers also found a "significant" amount of methamphetamine and ammunition, but no firearms at the scene, the jury heard. No charges were laid.
Jury's lawyer, Bill Nabney, suggested police had made dealings with Maney to make another statement about Rikihana's death and in turn, he would not be charged for the drugs found at his property.
Later in the day, Pathologist Rexson Tse took the stand and described the large number of injuries found on Rikihana's body after he died.
He talked about "significant head and neck" injuries including neck and face abrasions, a number of facial bruises, a fractured nose and bad lacerations on both the side of his lips and the back of his head.
The injury on the back of his head had caused his scalp to be ripped from his skull and his brain-injured, he said. Being hit with an object with "substantial force" could cause this.
Tse said that some of Rikihana's injuries could be consistent with being struck by a section of a hammer.
He also had a number of injuries on his body including fractured ribs and wrist abrasions consistent with being tied up.
Meanwhile, the hammer thought to have been used in the killing of Rikihana was brought out in court in a resealable plastic bag.
It was part of the Crown's questioning of Detective Dennis Nairn who was the lead officer of the crime scene at Rikihana's home on January 30.
The investigation of the scene took place over three days where a number of blood stains were found on paving surrounding the house, on the bin and on the light switch of the victim's bedroom.
The High Court trial began in Rotorua on Monday before a jury and Justice Paul Davison.
The trial is continuing.