Here's how it was taught to me back in law school. If police are executing a warrant, they can lawfully search anywhrre the item could reasonably be found. If in the course of that search they find something which is obviously contraband or evidence of friminal activity, it can also be seized even if not specifically listed in the warrant. In my own experience, while police were executing a warrant on a meth lab, there was a credit card laying on a table. Bad news for the meth cooks, it was the cop's mother-in-law's card, and her home was burglarized two days earlier. I don't know about the OP, though. Tough call. It's why I had my guys photograph everything they found as they found it, to help the suppression hearing issues.