Because it's the only shot in the dark at stopping a violent murderer when Maryland accidentally releases him into the wild.
Of course I'm kidding about the gun law part, but Maryland is chock full of elitist politicos who have made it very hard to protect yourself from dangerous criminals in the belief that these laws will make it difficult for the dangerous criminal to get access to a weapon. It's a foolish belief.
Understandably accidents happen, but the millions of people in the area around the prison are now more vulnerable to this scumbag by being disarmed.
Update: Scumbag in question memorized another scumbags identification number. Pretty high tech prison system going on there.