Gonegirl the reason the police officer thought he had a gun was because the raid on him was ill prepared on inadequate information, which was later proven to be entirely wrong.
Read the inquiry report.
A police force was to blame for the fatal shooting of an unarmed man, a public inquiry has concluded. A judge said the shooting was legally justified, but said the operation had been organised and planned "incompetently". Senior officers "failed to authorise, plan or conduct the firearms operation in such a way as to minimise recourse to the use of lethal force"
The officer who shot him told the inquiry he fired as he thought Mr Grainger had reached down to pick up a firearm. The judge said the officer,"honestly but mistakenly believed Mr Grainger was reaching for a gun". He jumped to that wrong conclusion because of the "misleading way his superiors had briefed him beforehand", according to Judge.
The judge said if firearms commanders had planned, briefed and conducted the deployment competently, Q9 "would have been less likely to misinterpret Mr Grainger's actions and might not have shot him".
All the responsibility for this killing lies entirely with the police.