A man accused of murdering his ill wife agreed to help her die after they watched a television documentary on euthanasia, a court has heard.
Frank Lund says he helped kill his wife out of love
Frank Lund, 58, smothered his wife Patricia, 65, with a pillow and a plastic bag at their home in New Brighton, Merseyside, in September.
He denies murder and insists she asked him to help her die.
Mr Lund told Liverpool Crown Court he had refused to help before relenting under pressure in August 2006.
The jury heard how the couple spent most of their lives in Hebden Bridge, West Yorkshire, before moving to Merseyside in 2002.
Mr Lund, a retired accountant, told the jury he had agreed to his wife's request after they watched a programme in which celebrities discussed how they would prefer to be helped to die.
He said: "It was done in a hypothetical way by three reasonably well known people, and they were talking about what they would do in terms of the mechanism of killing themselves, including suffocation with a plastic bag."
Mr Lund told the court he decided to help his wife to die on 17 August following a "very sad discussion", in which she said it should be her right to choose.
He said: "I don't know why I felt differently. Perhaps it was the accumulation, but it did strike a chord with me that it was her choice.
"I went to bed and when I woke up it was absolutely clear in my mind."
He said he made a "solemn vow" his wife that she would die with dignity, in her own bed, on a day of her choosing.
He told the jury that on the morning of 1 September she said: "Today's the day. I want to do it today."
He said: "I knew exactly what she meant because there was no other topic of conversation by then."
He explained how he went to buy nearly 100 paracetamol tablets, along with roses and farewell cards.
He said Mrs Lund took the tablets and began vomiting, but refused to go to hospital.
Andrew Menary QC, defending, asked if he considered taking her against her wishes.
Mr Lund replied: "That would have been equivalent to the greatest act of disloyalty and betrayal I could have rendered against her. I would have been better to just desert her than to do that."
Earlier, the jury heard that the Lunds were a "passionate and devoted couple".
Mrs Lund was described as a "complex" woman who suffered depression and had made five suicide attempts since the mid 1970s.
The trial was adjourned until Tuesday.