I'm just telling you what the judge said. The fact of the matter is, the cop in charge of this investigation is grasping at straws. He claims he wants to establish whose bedroom it was, yet he gathered no relevant information regarding that matter. His claim is that whoever bought the book must have been the bedroom's occupant, and for some reason he didn't find it necessary to check the room for prints, search credit card records to see who bought any of the other stuff in the room, ask friends and neighbors, or whatever a normal detective would do to ascertain such info. Heck, I'm no detective, but it seems obvious to me that if you want to know whose room it is, you should be checking stuff like prints and maybe hair samples found in the bed or something like that.
The books were never even looked at, so any meth manufactured in that home was manufactured with no help from those books. If there was actually lab equipment that was used to manufacture drugs, the equipment could be tested for chemical residue. There were precursor chemicals purchased by the suspect. Weren't those found at the scene? Fingerprints on the equipment--did those match the suspect's prints?
Essentially, the judge's main point is that, since fundamental rights are implicated in this case, the government needs to show that its "need for this evidence is sufficiently compelling to outweigh the harmful effects of the search warrant." But the City already has strong enough evidence to make its case without the invoice information, so the government's need is not compelling enough.
It reminds me of John Waters' Pink Flamingos when the mailman comes to Divine's trailer with a package (from her enemies). "She" says that it is a trailer and that it doesn't have an address.
The label is written "A Trailer".