If you were arrested for busking in Montgomery County Maryland, it would be illegal for any county employees to make any inquiry or comment as to whether you were a documented or undocumented alien.

Furthermore, the county provides a couple day labor centers where illegal workers in need of work are encouraged to come--You could get in trouble if you actually have some sort of visa, and violated the terms thereof, but as an an out and out illegal immigrant worker, you would be OK--