The final day of an inquest in Launceston has heard evidence from the investigating inspector and the policeman who fatally shot a man at his Westbury home in 2010.
The officer in charge of the crime scene, Inspector Timothy Doolan said there was no explanation for why the discharged shell was found in the yard, when the shooting apparently happened in the kitchen.
Inspector Doolan says the investigation drew the attention of the Integrity Commission.
Senior Constable Ian Blake has recounted how Mr Whiteley became agitated, was not subdued by capsicum spray and that he took the officers spray and used it on him.
Constable Blake says Mr Whiteley began a frenzied attack and threatened to kill the officer, and that he still believed shooting the man was his only option.