I'm not too sure about MD, but in VA and DC I ride with no mirrors or turn signals, a blinky for my taillight, and no brake light. If they say something about it, VA law says that you're riding a motorized bicycle, bicycles don't need an electronic signaling system or rear views. DC could care less.
I use hand signals when I can.
Bring that magnum out Andy, lets ball. What's up for this Saturday afternoon? You got a chain tool that works on 415?