A pensioner who shot his 81-year-old wife dead at a care home has been sentenced to six years in a psychiatric hospital.
Ronald King, 87, formed the "settled intention" to kill his wife Rita, whose dementia had worsened in the months before her death, Chelmsford Crown Court heard.
Judge Charles Gratwicke said the manslaughter was "not a mercy killing", but accepted that King was suffering from dementia himself and that this had impaired his ability to form rational judgments.
King shot his wife of 50 years in the communal television room of De La Mer House in Naze Park Road, Walton-on-the-Naze, Essex, on December 28 2015.
The weapon used was his father-in-law's old service revolver which he took to the care home from his home address, and his wife died instantly as a bullet passed through her right eye.
He had also planned to kill his sister, who was also a resident at the home, and then to kill himself.
King, of Cedar Close, Walton-on-the-Naze, denied murder at an earlier hearing, but pleaded guilty to a lesser charge of manslaughter on the grounds of diminished responsibility or by survivor of a suicide pact.
Judge Gratwicke, sentencing, said: "This was from every angle a tragedy."
King had told police he wanted to stop his wife suffering any more.
But Judge Gratwicke said: "As you will know, there's no evidence that she was in pain or suffering any more than anyone else who has succumbed to dementia. This was not a mercy killing.
"Rather, it was a killing that occurred at a time when the experts agree that you were suffering from dementia causing an abnormality of your mental functions.
"Your ability to form a rational judgment was substantially impaired when you came to the settled intention to kill your wife."
The court heard King mistakenly believed care home staff were stealing from his wife and drugging her.
It was a "carefully planned" killing, with King filing down the nose of a bullet to ensure his wife died.
The judge accepted that King had been a devoted husband to his wife, strived to took care of her and that there was no malice in her killing.
King was also in ill health.
Professor Graeme Yorston, consultant forensic neuro-psychiatrist, said King's frontal lobe was affected by his dementia, and this part of the brain was responsible for forming rational decisions.
"That's what led him to come to the conclusion that, because of his perception of inadequacies at the care home, his only possible response to that was to shoot his wife and also himself and his sister," he said.
Patrick Upward, mitigating, said: "Had it not been for the intervention of this disease, the offence would not have taken place."
He added: "His punishment is the separation from the woman he was married to for 50 years and everyone who has spoken to them describes them as an affectionate and devoted couple."
King was sentenced to six years for manslaughter, five years for possession of a firearm, 12 months for possession of ammunition, with the custodial terms to run concurrently and to be served in a secure psychiatric hospital.
If King is deemed fit enough to leave the hospital before his sentence is completed, the remainder of the custodial term will be served in a prison.
Reporting by Press Association
