The crown alleges a man used a pillow to smother his elderly sister while she slept under medication at her home seven years ago.
Denis Kenny Billesdon, 71, was before a depositions hearing in Christchurch District Court on a charge of murdering Nola Doreen Billesdon, 77.
Crown prosecutor Chris Lange said Billesdon had spent the day with his sister on February 18, 2001, and then returned to her home in the evening ready to stay the night.
He said Billesdon administered liquid morphine and sleeping tablets to the woman and then went to her room about 8pm and put a pillow over her face.
He then fixed things in the room to make it look as though she had died in her sleep. He dialled 111 from his home three hours later.
Miss Billesdon's death was not thought to be suspicious at first, although the doctor would not sign the death certificate because he said no ailment was bad enough to cause death.
Mr Lange said Billesdon had told two people about smothering his sister with a pillow, in comments he made in 2005 and 2006.
The crown will call 27 witnesses but most of their evidence is being handed to the JPs in written form. The depositions are expected to run for three days.
A friend of Billesdon told of him saying something bad had happened but he would not say what. He also inquired about getting a firearms licence.
Billesdon had severe health problems and was not happy with himself or life in general, the friend said.
Dr William Kirkwood detailed a long list of health problems faced by Miss Billesdon, including five hospitalisations and one emergency department visit in the two months before her death. He requested a post mortem because he was not sure of the cause of death.
Billesdon's wife Helen said the couple had looked after Miss Billesdon during her health problems.
She also said Billesdon had wanted the contents of his sister's will changed so that he would inherit the house and pass it on to his children. He took Miss Billesdon to a lawyer so that the changes could be made.
