Heckler’s veto, anyone?
The Volokh Conspiracy 2015-12-22
Summary:
Riders of the D.C. Metro will recognize the above poster, which appears on the side of Metro cars and on the walls of Metro stations. The text — hard to make out in the photo I snapped — reads: “You have the right to be safe waiting for and riding Metro. You don’t have to put up […] 
