So, I get a notice at my house/po box that there's a package addressed to me that has to be signed for. Isn't it human nature to be curious what's in the package? Whether or not I ordered it? I'd sign for it to find WTF it is.
Why is it an admission of guilt to want to know what's in some mystery package? I don't see that holding up in court. I'd tell the judge it must have been sent as a prank. Or by someone trying to get me in trouble.
Could a prosecutor actually use such flimsy evidence to get me convicted? IANAL - so maybe I'm missing something here.
I don't know what country you're in. But up until you sign for a package here (UK) the mail is property of the crown. So it's not an admission of guilt, it's you confirming the package is your 'property' - and you can therfor be convicted for it. I don't really think the police care if someone sent you it as a prank - Otherwise there would be a lot of people using their get out of jail free card with 'That's not my crack, my friend must've left it in my house!'