Legal Question in Criminal Law in North Carolina

First, affidavits are merely written statements that are sworn to. They may contain negative things about you but they aren't really 'against you'. As to whether you can ask to see it thru the mail - sure, you can ask. If you can speak and / or write you can ask for virtually anything. The real question is whether or not asking will get the results you want - the answer to that is maybe. If they won't voluntarily give you a copy, depending on the circumstances of the situation there may be ways to force them to provide a copy.