Calabrese said Accardo himself killed Mooney. Makes sense, I think it was John Roselli or Accardo that killed Sam.
It's possible that it was Accardo, but it's a little hard to imagine someone that high up would want to take that risk. It also seems out of character. Maybe he figured it was the only way because Giancana didn't want to meet with anyone. Blasi was always going to be the main suspect, so it doesn't really make sense to give him the contract.
