Invercargill policeman Ben McLean is due to be sentenced after pleading guilty to murdering his wife and the attempted murder of Garry Duggan.
The 48-year-old will appear in the High Court in Invercargill before Justice Rachel Dunningham at 9am on Monday for sentencing.
He had pleaded guilty in the same court last Thursday.
McLean shot his wife of 20 years, 40-year-old Verity McLean, in the head with a sawn off .22 rifle on Anzac Day this year in the Invercargill suburb of Newfield.
He later shot Mr Duggan twice, hitting him in the upper chest and the forearm.
The two struggled and Mr Duggan wrestled the rifle from McLean.
McLean handed himself into the Invercargill police station, where he worked, 40 minutes after the shooting.