I believe that incident happened in the fall of 1950. It was one of the Chiofano brothers. Giovanni and Lorenzo were in prison at the time, and Paolo was hiding in Australia. I believe it was Umberto who slapped Luciano, he was not made (Giovanni and Paolo were) and was killed soon after.

"I have this Nightmare. I'm on 5th avenue watching the St. Patrick's Day parade and I have a coronary and nine thousand cops march happily over my body." Chief Sidney Green