hmm...
I like the idea, and I think you'll do well with it, but have they overlooked something in this device?
if it can manipulate atoms freely, then wouldn't it be able to dissasemble already-formed objects?
perhaps the sand or whatever would be the easiest to manipulate, but I would think anything would be usable, some things better than others, but I would imagine ethical reasons (destruction of property and such) for police not to. perhaps the police would all have individual allotments of sand in containers on their belt or somesuch.
regardless, I like the idea, specifically the restrictions on removal, and I look forward to watching more.
keep working!