dead letter box

noun

1. a place where messages and other material can be left and collected secretly without the sender and the recipient meeting

Example Sentences

At an elegant country house in Hampshire, Jack and his colleague Sandy, and an efficient girl called Emily, whom I immediately fell in love with, gave me the short course in clearing a dead letter box in mid-town Kiev — actually a chunk of loose masonry in the wall of an old tobacco kiosk — of which they had a replica set up in the orangery.

From New York Times

The judges, however, dismissed arguments that the delay was caused by an “overburdened system,” saying the VA essentially put their court order in a “dead letter” box.

From Washington Times

Even if Margolis had followed OPR's recommendation, the cases would almost certainly have wound up in the dead letter box.

From Slate