That news will be of no comfort to Clark, who said she and husband Colin were "absolutely devastated" over the loss of Dean.
"He was such a loved and cherished boy and he had a wide selection of friends. Our house is filled to the brim with flowers, there were so many people who loved him."
She said her son, who loved bikes and tennis and was an accomplished skateboarder, had known the man accused of killing him for 10 years. The man moved into the house with him just a week before Dean's death.
"The mental health system has absolutely failed. The laws need to change and become more stringent but this is not the time to talk about that."
She said her son had been training to become a barista after leaving a car-painting job because of ill health. He had much to look forward to in life.
Recently retired mental health worker Robin Guy believes that potential could have been fulfilled if gaping holes in the mental health system had been fixed.
The man accused of the murder was friends with two other mental health patients who died earlier this year. The friends would meet at drop-in centres around Auckland or get together for a drink.
But Carl Andrew Smith, 38, died last month and Sion Antony McKay, 36, was found dead in February.
Guy knew all three through his work housing the mentally ill. He said the three men were highly intelligent and artistic but had struggled with mental health issues and - like many others before them - had fallen through the cracks.
"They all liked art, and music, they were unemployed so they would get together and socalise together, and unfortunately sometimes they drank."
Like many community-based patients the men had little money, expensive accommodation costs, and had resisted medication and help, Guy said.
"The support systems are inadequate for people like them and things get worse with the tightening of money," he said.
Auckland District Health Board confirmed an internal review would be held over the treatment of the man charged with murder.
