Especially keep a look out for SUVs and Minivans with dark window tint. They may be lazy parents hiding a child in there.
https://family.arlingtonva.us/notevenforaminute/
And if you are one of those crazy freerangers who does @#$% like this on purpose and you are going to argue with me on this (and Arlington County) have the balls to include your name, license plate number and kids ages.