The charge resulted from an incident on October 12, last year, just days after his wife's admission into a Waikato aged care facility, after living together happily for nearly 60 years.
The court summary of facts state that after her stroke on August 15, the wife was hospitalised for eight weeks before being admitted to the facility.
She had several physical and mental disabilities which resulted in her being admitted into the aged care facility.
The man wasn't happy with the care she was receiving and on October 8, her first night there, he removed her and walked her back to their home a short walk away.
Police were called and arrangements made for her safe return the next day.
However, prior to her being returned that morning, the man attempted to kill himself and his wife in the car.
A recording was found by police in which the man is heard telling his wife that they will both die of carbon monoxide poisoning and they are both doing a "murder-suicide".
In the recording the car engine can be heard running in the background.
Over the coming days, the man continued to visit his wife who was now back at the facility, and his attitude toward her situation worsened.
On the afternoon of October 12, he visited his wife and asked staff if he could take her for a walk around the grounds in a wheelchair.
However, instead of taking her for a walk, he took her home and put her in their car.
In the car, he had tubing, rolls of duct tape and a knife with which he intended to use to end his and his wife's life.
Before they left the house, the man sent an email to a number of close friends and family overseas detailing his frustration and saying they were going to take their own lives.
He then drove to a location where he attempted to take his and his wife's life again.
A passing motorist saw the man getting prepared and stopped his car.
After being spotted, the man cleared his car and drove off, but not before the motorist had called police and attempted to follow him.
The man drove to Lake Karapiro and was approached by police and taken into custody.
His wife was not injured.
The man later told police that his wife had agreed to a suicide pact and that she was keen to end her life.
Police later found another iPad recording dated October 12 when the man stated that all the events about to take place were his wife's idea.
About a week later his wife was assessed by Waikato DHB staff.
They found she lacked the capacity to understand and foresee the consequences relating to her personal care, finances, welfare and medical care.
The DHB found she had difficulty understanding information, communicating and was unable to display signs of reasoning.
She was assessed at being significantly vulnerable to exploitation, the summary of facts stated.
The man was convicted by Justice Toogood and remanded for sentencing on May 14.
Justice Toogood also issued the man with a warning under the three strikes legislation.
Where to get help:
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youth services: (06) 3555 906
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• Helpline: 1737
If it is an emergency and you feel like you or someone else is at risk, call 111.