Here is the email I recieved from DNR, the only edit was removal of my email address -
Apparently DNR doesn't prevent it and I have seen nothing else that does so go for it.From: Customer Service <customerservice@dnr.state.md.us> [Add to Address Book]
To: Ken King
Subject: RE:{MDDNR#518-923}HUNTING QUESTION
Date: Oct 30, 2007 10:44 AM
Maryland has no Natural Resources law that specifically prohibits the use of a silencer. You must check with the Maryland State Police regarding the laws prohibiting possession of a silencer. You should also check with the Alcohol, Tobacco and Firearms of the US government about possessing such a addition to the weapon.