Refers to the movie of the same name where one character tells another "if you ever kill someone, never tell anyone else about it.' If you do anything wrong keep it to yourself.
"Bob sent me a email about how he stole a laptop from work. Way to violate the Layer Cake Rule"

"I really wanted to tell the guys how I scored with that waitress on my business trip, but I thought of the Layer Cake Rule, and how it could get back to my wife."
by SnowPatrol July 30, 2010
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