Jeremy told them his sister was a nutter and that his father told him she had had gone crazy and had a gun. He described numerous weapons and told police she had used them in the past including the rifle he claimed he left on the kitchen table which he said he taught her how to use.
Since he realized that would look suspicious that he taught her how to use it he changed his claims and when questioned by Jones and Ckark said she shot with others not him , he never knew her to fire a weapon.
Police didn't put any words in his mouth he blamed Sheila when calling West, talking to police on the scene and his statements.
Police started to question Jeremy about Sheila at the scene shortly after arriving there at 3.52am, because by that stage Ralph himself had alreasy contacted the police and told them (3,26am) that "my daughter has got hold of one of my guns"...
Police instigated the questioning of Jeremy at the scene, and later, because they had information from Ralph himself that Sheila was loose inside the farm house in possession of one of Ralph Bambers guns. Jeremy did not know that his father had phoned the police or what Ralph had said to them - police were simply gathering intelligence about Sheila's mental and psychological condition, and also trying to find out if Sheila was capable of using any gun that she might currently be in possession of...
The only reason some confusion has arisen regarding where Jeremy says he left the rifle on the previous evening, is because the family regarded the area just inside the rear external court yard door as 'the back kitchen', and the 'main kitchen' being the one with the aga stove and surround. He placed the rifle on the seat of a wooden settle near to the door in the back kitchen, not on the table in the main kitchen...