A Mongrel Mob member already deemed one of New Zealand’s highest-risk violent offenders launched a frenzied chair attack on a 73-year-old Corrections staffer while detained under a rare Public Protection Order, a court has heard today. 

Sonny Tearamoana Waiti, 38, pleaded guilty this morning to wounding with intent to cause grievous bodily harm and threatening to kill over the January attack at the secure Christchurch residence where he was being held indefinitely. 

CCTV footage captured Waiti repeatedly smashing plastic chairs into the elderly victim’s head and body as the man begged him to stop, leaving him with extensive injuries and believing he was “going to die”. 

During the attack, Waiti told the man, “I will kill you”. 

Sonny Te Aramoana Waiti in the Rotorua District Court. Photo / Ben Fraser

Waiti has a lengthy criminal history, including a six-year prison term in 2013 for dragging his girlfriend nearly 2km behind a car. 

The patched Mongrel Mob gang member locked the woman in a car boot after accusing her of cheating on him. 

He then drove erratically along State Highway 1 between Tokoroa and Putaruru. 

The woman tried to escape but her foot got caught and she was dragged at speeds of at least 90km/h for at least 1.6km. 

She suffered injuries to much of her body and her left leg was later amputated below the knee. 

Waiti has already received two strike warnings for serious violent offending and was subject to a Public Protection Order (PPO) when he attacked the Corrections staffer. 

A PPO is a court order that allows the detention of very high-risk criminals at a secure facility within prison precincts. 

They are civil detention orders that can be put in place for offenders who have served a finite prison sentence, but still pose a very high risk of imminent and serious sexual or violent offending and cannot be safely managed in the community. 

A PPO is indefinite and has no expiry date. An order can only be cancelled if the High Court is satisfied that the offender no longer poses a “very high and imminent risk”. 

Corrections said “only a very small number of people” are subject to PPOs - they were “individuals who have served a prison sentence for a serious sexual or violent offence AND continue to pose a very high risk of imminent and serious sexual or violent offending”. 

“To be subject to a PPO an offender must have ALL of these characteristics to a high level: an intense drive or urge to enact the particular form of offending; very poor self-regulatory capacity, evidence by general impulsiveness, high emotional reactivity and inability to copy with or manage stress and difficulties; absence of understanding and concern for the impacts of their offending on actual or potential victims; poor interpersonal relationships and/or social isolation,” Corrections states. 

Waiti was made subject to a PPO on June 25, 2024. 

Since then, he has been detained at a residence on the grounds of Christchurch Men’s Prison - the only purpose-built facility for offenders subject to a PPO. 

His latest offending happened on January 20. 

The victim was a 73-year-old Corrections staffer who worked part-time as an assistant supervisor at the residence Waiti was housed in. 

Because he is not a Corrections Officer, he was not wearing personal protective equipment such as stab-proof vest and he was not armed. 

Just before 9am, Waiti was with the victim in a communal hub within the residence. 

CCTV footage showed Waiti taking a rigid plastic chair from a dining table and moving to sit against a wall. 

Soon after, the victim walked in and greeted Waiti. The pair engaged in conversation and the victim sat on a desk in the corner of the lounge area. 

Christchurch High Court. Photo / George Heard

The men watched a morning news show for about a minute before Waiti got up and walked across the room. He removed photos of Jesus Christ and scripture verses from the wall and put them on the dining table. 

He then walked to the door and “briefly looked outside”. 

For the next few minutes, Waiti moved around the hub. At 8.52am he walked outside, and when he came back seconds later, he attacked the victim. 

“Suddenly and without warning [he] picked up the rigid plastic chair that he had earlier been sitting on and attacked the victim,” the summary of facts states. 

“[He] held the top back of the chair and swung the chair up in the air and down onto the victim, striking him with the legs of the chair in the chest area. 

“The victim put his hands up to try and fend off the blow. The victim then stood up to try and get away and as he did so [Waiti] swung a punch at him ... which appeared to miss.” 

Waiti then punched the pensioner in the back. He dropped the chair and shoved the victim forward into the wall, “swinging a roundhouse punch” at his head. 

He grabbed the victim by the collar and threw him to the ground on top of the plastic chair. 

The victim’s head “crashed” into the side of a nearby couch. 

“[Waiti] then stomped on the victim ... while the victim was prone on the ground, and remained on top of the victim, pinning him to the ground,” the summary states. 

“[He] then stood up, with his right foot on the victim’s chest and grabbed the chair ... raised the chair high above his head before bringing it down on the victim’s body with considerable force.” 

Waiti struck the victim two more times, delivering the second blow “with such force that” his own cap fell off his head. 

The attack did not end there. 

Waiti moved positions and continued striking the victim 12 more times with the chair using “full force”. 

“Each time, raising the chair high above his head and striking the victim to his upper body and head,” the summary revealed. 

“The victim was begging [Waiti] to stop.” 

Before each strike, Waiti “respositioned himself” to make sure that the chair struck the victim in the head and upper body. 

On the last strike, a piece of the chair broke off because of the force Waiti was using. 

“[He] then discarded the broken chair and grabbed an identical chair ... he took the same grip on this chair ... and again raised it high above his head to strike the victim who was still on his back on the ground, bleeding profusely and trying to ward off the attack,” said the summary. 

“The victim put one leg up to try and block the chair, however [Waiti] quickly moved himself around to avoid his outstretched leg and delivered a direct blow to the victim’s face with the chair. 

Waiti delivered a second direct blow to the man’s face and chest. 

“At this point, the victim tried to grab the chair legs to stop [Waiti] hitting him,” the summary continued. 

“[He] easily overpowered the victim’s grasp, wrenched the chair out of his hands and resumed striking the victim with the chair - again positioning himself to avoid the victim’s legs and target his chest and face, to deliver another two blows.” 

The victim kept trying to grab the chair but Waiti “easily” pulled it from the older man’s grip and moved around “so as to get a clear shot at his head”. 

CCTV footage shows blood spatter from the victim’s injuries on the floor around where he lay. 

Waiti continued to hit the victim, at one point striking him “directly in the face with such force that parts of the seat of the chair broke and scattered around” him. 

“The chair then had sharp edges from where it had broken and [Waiti] continued to strike the victim,” the summary said. 

“The chair ... had visible blood covering one of the legs.” 

The attack continued and soon the victim was bleeding heavily as the sharp edges of the chair were causing “deep lacerations” to his face and arms. 

Waiti stood “up onto his tiptoes for more downforce” and, as he “smashed” the chair down, the victim grabbed it, causing the attacker to “stumble backwards”. 

He let go of the weapon at that point - just before another staff member rushed into the room. 

Waiti backed away and picked up a third chair. 

The second staffer picked up a damaged chair and “tried to de-escalate the situation”. 

“Other employees went to the aid of the victim and also picked up chairs to keep [Waiti] away,” said the summary. 

“[He] continued to pace around the dining table holding the chair ... in a threatening way.” 

Staff ordered Waiti to put the chair down and leave and eventually he left the lounge area. 

CCTV footage showed that Waiti hit the victim 21 times with the chairs, punched him three times and stomped on him once. 

The victim later said he thought he was “going to die”. 

During the attack Waiti told him “I will kill you, old man”. 

The victim was rushed to hospital. His injuries included a broken left wrist and thumb; bruising across his chest; lacerations, bruises and abrasions to his face; lacerations to his left forearm that were so deep muscle was “bulging” from his wounds and he needed 39 stitches; a further eight sutures to cuts on his right arm; a “large chunk of flesh” was cut from his right hand; a broken tooth that required wiring and three other damaged teeth. 

He also suffered “ongoing issues” including concussion, blurred vision, headaches, neck pain and Post Traumatic Stress Disorder. 

Waiti appeared in the Christchurch High Court this morning before Justice Cameron Mander. 

He pleaded guilty to both charges and will be sentenced in August. 

Anna Leask is a senior journalist who covers national crime and justice. She joined the Herald in 2008 and has worked as a journalist for more than 20 years with a particular focus on family and gender-based violence, child abuse, sexual violence, homicides, mental health and youth crime. She writes, hosts and produces the award-winning podcast A Moment In Crime, released monthly on nzherald.co.nz