I don't think you'll find anything specific beyond the obvious removal of Laptops and Deodorant. Plus these aren't exactly "Laws" as far as I know, as in there's no law "14.2(a) You must remove laptops at security screening point"
It'll likely be a very general law that you must pass security screening. To do so you'd need to remove your Laptop as it can block their proper view of whats inside also, for exmaple, in the past I've been asked to remove a few items such as wires and cables which made things inside look basically like Bomb wiring!
The basics are that they can ask you to remove whatever they like. I'd suggest not making a fuss about it as they're just doing their job, things can get in the way, for example my iPad Kneeboard has a bit piece of metal so I usually lay it so that's on the bottom and doesn't cause problems with their view and I keep my cable neatly wrapped up inside the bag which has reduced those problems for me.