 The prosecution added that the likely motive for the killing was he had decided that it was time for Mrs Morrell to die, as he feared her altering her will to his disadvantage.In strict law, the prosecution did not need to show a motive but, if none were advanced, the offence had to be proved by demonstrating beyond doubt how the killing was carried out.Throughout the trial, the prosecution maintained that the motive was a mercenary one, and it did not rely on the possible alternative of euthanasia.