Vidvic in #83 there's a reference to the silencer which was discovered resting against the box in the gun cupboard and not inside(and therefore concealed from open view). I'm still not clear whether four separate Police officers looked inside the cupboard or PC Woodcock looked inside it four times,but it does seem strange that it wasn't noticed straightaway.
I can not stress enough how hard it is to see inside the cupboard. I will try and describe it. If you get down on all fours you can see the back of the cupboard in front of you, but as it is the understairs cupboard, it actually goes much further to your right....but it is not a flat floor. There are wooded cross members which prevent you seeing anything laying on the floor behind them and you have to physically put your hand behind them and feel for objects. It goes quite a way back too....so anybody simply looking in would never see anything smaller than say, 3 or 4 inches tall as it would be behind the wooden beams. I am 5ft 10 and it goes so far back that my bum was in the cupboard before my hand reached the far right end. Hope this helps.