The knocking aside of papers doesn't yield anything, unfortunately, except for papers the Sheriff will have to pick up at some point. If he comes back, that is.

But there is something they will see. It's subtle, but between the cracks of one of the filing cabinet drawers, there's a soft glow that can be seen. If someone tries to pull it open, she'll discover that it isn't latched and is, indeed, the object that clicked open a few minutes before.