Earlier in the day three men arrived and the foursome, the three men and Mickey that is, whom witnesses say were in jovial mood, went out for a stroll along the boardwalk. Later they went into Mickey's suite for lunch and at some point in the early afternoon Mickey laid down to take a nap. As he slept his pal(s) shot him to death.
It was assumed that Mickey was done in by his own gang whom were unhappy with his management. Apparently he had to close down a brewery and was also under Federal indictment for shaking down trucking lines that traversed the south Jersey roadways. Though he had been wounded in a 1927 shooting in Philadelphia, in which his bodyguard had been killed, he felt safe in Atlantic City and didn't have any security.
Oh, for some reason everyone seems to think he was killed on the 30th or 31st, but as Mickey Duffy himself used to say, "You can't believe everything you read on the internet."